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[Illustration: A SOUTHERN MICHIGAN WOODLOT]


   UNIVERSITY BULLETIN
   NEW SERIES, SEPTEMBER, 1915 VOL. XVII, NO. 10

   UNIVERSITY OF MICHIGAN
   BOTANICAL GARDEN AND ARBORETUM

   MICHIGAN TREES

   A HANDBOOK OF THE NATIVE AND MOST
   IMPORTANT INTRODUCED SPECIES

   _By_

   CHARLES HERBERT OTIS, FORMERLY CURATOR

   WITH AN INTRODUCTION BY

   GEORGE PLUMER BURNS, FORMERLY DIRECTOR

   [Illustration]

   Ann Arbor
   PUBLISHED BY THE REGENTS
   1915

   COPYRIGHT, 1915

   BY

   THE REGENTS OF THE UNIVERSITY OF MICHIGAN

   THIRD EDITION, REVISED

   THE ANN ARBOR PRESS, PRINTERS
   ANN ARBOR, MICH.


TABLE OF CONTENTS.

                                                             PAGE

   A Southern Michigan Woodlot--_Frontispiece_.

   Map of Michigan (Showing Details Mentioned in the
   Bulletin)                                                   iv

   Introduction                                                 v

   Acknowledgments                                            vii

   How to Study the Trees                                      ix

   Artificial Keys, How Made and Used                       xviii

   Summer Key to the Genera                                   xxi

   Winter Key to the Genera                                 xxvii

   Manual of Trees (Description of Species, with Summer
   and Winter Keys to the Species)                         xxxiii

   Glossary                                                   231

   Index to the Artificial Keys                               241

   Index to the Trees                                         242


[Illustration: MAP OF MICHIGAN

SHOWING ONLY LOCATIONS MENTIONED IN THE MANUAL]




INTRODUCTION

The idea of a bulletin on Michigan trees was first suggested by Prof.
Volney M. Spalding. It was thought that a bulletin devoted entirely to
the study of certain phases of tree life in Michigan would stimulate
interest in the study of our trees, and influence many more people to
associate themselves with the growing number of tree lovers and with the
supporters of the movement for better forest conditions in the state.

The bulletin has been under consideration for a number of years and much
of the material given herein has been used in the classes in forest
botany at the University of Michigan. It remained, however, for the
present Curator of the Botanical Garden and Arboretum to get the
material into shape for publication, and the present bulletin is the
result of his industry and perseverance. The preparation of the drawings
and manuscript has been made by him in connection with his work in the
Garden.

The distinctive feature of the bulletin lies in its keys. The keys
commonly published are based upon characters which are present but a
short time during the year, or which can be used only by an advanced
student of botany. This bulletin presents two keys. One is based upon
characters which are present all summer; the other uses the winter
characters as a basis for identification. By the use of the keys any
person should be able to name and learn the characteristics of the trees
of Michigan at any time of the year. These keys should prove of special
value to our students in the public schools, to members of nature study
clubs, and to the students in the forestry schools of the state.

The order of arrangement and the nomenclature are essentially those of
"Gray's New Manual of Botany." Following a tendency which is steadily
gaining favor, all species names are printed with a small letter,
regardless of their origin. For the convenience of the general reader,
other scientific names which are found in botanical manuals _in common
use_ are printed in parenthesis. In the case of exotics which are not
included in the Manual, other authorities have been followed. Sudworth's
"Check List of the Forest Trees of the United States" (U. S. Dept. Agr.,
Div. Forestry, Bul. 17) is in most cases authority for the common names.
They are names appearing in common use today in some part of the state.
The first name given is that recommended by Sudworth for general use.

The drawings have been made from living or herbarium material and are
original. They are accurately drawn to a scale, which is given in each
case. In their preparation the author has endeavored to call attention
to the salient characters. In the drawings of buds and twigs certain
points, bundle-scars, etc., have been emphasized more than is natural.
In the descriptions the attempt has been made to bring out those points
of similarity and contrast which are most useful for identification.

As the bulletin is not written especially for technical students of
botany, the author thought best to use as few technical terms as
possible in the descriptions. In some cases it was impossible to avoid
such terms, but with the help of the glossary the meaning can be easily
understood. Any person desiring to get a more complete knowledge of
trees should consult one of the larger manuals. The arrangement used for
the illustration and discussion of each single tree makes it possible
for the student to compare the drawings with the description without
turning a page.

It is believed that with the aid of the drawings and descriptions given
in this bulletin any person will be able to name the trees which grow in
his yard, park, or woodlot. If, however, any difficulty is found in
naming the trees, the Curator will be glad to name any specimens which
may be mailed to him. He would be glad to get in touch with persons
interested in Michigan trees and to receive any additional information
relating to the subject. Data concerning the distribution of the trees
in the state, and the addition of other Michigan trees to the present
list would be of especial value.

GEORGE PLUMER BURNS.




ACKNOWLEDGMENTS

Grateful acknowledgment is hereby made to Miss Sarah Phelps, who has
done most of the inking in and given life to the author's
pencil-drawings; to Mr. J. H. Ehlers for his valuable assistance in the
preparation of many of the drawings and in the collection of working
material; to Prof. Henri Hus, who has read all of the proof and who has
at various times rendered valuable assistance; to Prof. F. C. Newcombe
and to Prof. Ernst Bessey for the loan of sheets, from the herbariums of
the University of Michigan and Michigan Agricultural College; and
especially to Prof. Geo. P. Burns in whose inspiration this bulletin had
its inception and under whose direction the work has progressed to
completion.

   CHAS. H. OTIS.




HOW TO STUDY THE TREES

People are everywhere associated with trees. Trees give cooling shade in
our parks and dooryards and along our highways; they lend their beauty
to the landscape and relieve it of monotony; they yield many kinds of
fruits, some of which furnish man and the animals of the forest with
food; and they furnish vast quantities of lumber for a multitude of
uses. How important it is, then, that every person, whether school-child
or grown-up, should become acquainted with our trees. Most people know a
few of our commonest trees, but are ignorant of the great wealth of tree
forms about them. Some who may have wished to go further have been
hindered for lack of a teacher or dismayed by the very multitude of
manuals to which they have had access.

In beginning a study of the trees the student should start on a solid
foundation, eliminating the uncertainties and the errors which no doubt
have appeared and retaining only the established facts. Once started he
should go slowly, assimilating each new discovery before seeking
another. He should begin with the trees nearest home, and, as he
gradually grows to know these in all their aspects, should extend his
trips afield. Not only should he be able to name the trees when they are
fully clothed in their summer dress, but he should as readily know these
same trees when the leaves have fallen and only the bare branches stand
silhouetted against the sky. Then, and only then, will he derive the
utmost satisfaction from his efforts.

The characters which are used in studying the trees are habit, leaves,
flowers, fruit, buds, bark, distribution and habitat. These will be
discussed briefly in the next few pages, the same order that is used in
the detailed descriptions of species being maintained in the present
discussion. A few drawings will also be added to make clear certain
points and to show comparative forms.

NAME.--Every tree has one or several common names and a scientific or
Latin name. Some of these common names are merely local, others have a
more extended use. Some few names apply to totally different species.
Thus, Cottonwood in Michigan is _Populus deltoides_, in Idaho and
Colorado _Populus angustifolia_, in California _Populus fremontii_ and
in Kentucky _Tilia heterophylla_. While it should not be forgotten that
in common speech it is proper as well as convenient to call trees by
their common names, yet, in view of the many uncertainties pertaining to
their use, a scientific name is at times absolutely essential to the
clear understanding of what is meant. Latin is the language in universal
use by all scientists. No longer used by any civilized nation, it has
become a dead language and consequently never changes. Its vocabulary
and its constructions will a thousand years hence be the same as they
are today. Being in universal use among scientists of all nationalities
no confusion arises from the use of a Latin word. The Oak in Germany is
known as _Eiche_, in France as _chêne_ and in Spain as _roble_, but the
Latin word _Quercus_ is the same for all these countries.

A scientific name as applied to trees consists of at least two parts, as
_Quercus alba_; the first named is the genus and is always written with
a capital letter, the second is the species and is written with a small
letter, the two names constituting the briefest possible description of
the particular tree. It is customary to add to these the name or an
abbreviation of the name of the person who first gave the name to the
tree, as _Quercus alba L._, the abbreviation standing for Linnaeus.
Sometimes a third name is used, as _Acer saccharum nigrum_, referring in
this case to a variety of the ordinary Sugar Maple.

Genera which bear a relationship to each other are placed in the same
family, the family name always having the characteristic ending--_aceae_.
Related families are again grouped into orders, with the characteristic
ending--_ales_. Orders are in like manner arranged into larger groups,
called classes, and the latter into still larger groups, divisions,
etc., each with its characteristic ending. Thus, _Acer saccharum nigrum_
(_Michx. f._) _Britt_. is classified as follows:

   Division--Spermatophyta
     Subdivision--Angiospermae
       Class--Dicotyledoneae
         Order--Sapindales
           Family--Aceraceae
             Genus--Acer
               Species--saccharum
                 Variety--nigrum.

HABIT.--Habit, or the general appearance of a plant, is an important
character of identification, especially as we become more and more
familiar with the trees. Two main types are recognized, based on the
manner of branching of the trunk, the upright and the spreading. In the
one the trunk extends straight upwards without dividing, as is typical
in most of the conifers, and in the other the trunk divides to form
several large branches and the broad, spreading crown of most of our
broad-leaf trees. The crown in either case may be regular in outline or
very irregular, straggling or straight-limbed. Moreover, the tree
growing in the open, where there is no crowding and there is plenty of
light, may differ very greatly from the tree in the forest, where the
struggle for existence becomes very keen. A short, thick trunk and low,
spreading, many-branched crown characterizes the tree in the open,
whereas the forest tree has a long, slender, clean trunk and a narrow
crown of few branches. In the descriptions of trees in this bulletin,
unless otherwise stated, the habit in the open is the one given. Again,
the tree may have been injured by storm or insect at some period of its
growth and its natural symmetry destroyed. Moreover, the age of a tree
has a great influence on its outline, young trees being generally narrow
and more or less conical, broadening out as they become older. We may
say, then, that each tree has an individuality of its own, little
eccentricities similar to those that make people different from one
another. And just as we have little difficulty in recognizing our
friends at a distance by some peculiarity of walk or action, so are we
able to recognize a great many trees at a distance by some peculiarity
of form or habit.

[Illustration: I. LEAF OUTLINES

Lanceolate. Ovate. Heart-shaped. Halberd-shaped. Linear. Elliptical.

Oblong. Oval. Orbicular. Oblanceolate. Spatulate. Obovate.]

[Illustration: II. LEAF TIPS

Acuminate. Acute. Obtuse. Emarginate. Mucronate.]

LEAVES.--With the advent of spring the buds of our broad-leaf trees swell
and burst and the leaves come forth and clothe the trees with mantles of
green, hiding the branches which have been bare through the cold winter
months. The evergreens, too, take on new color and begin a new period
of growth. It is the leaves which the beginner finds most interesting
and in which he finds a ready means of identification. It must be
remembered, however, that leaves vary greatly in size and shape and
general appearance. How large are the leaves on a flourishing sprout and
how small on a stunted tree of the same species growing near by, but
under adverse circumstances. How different are the leaves of the big
white oak standing in the yard; they are hardly lobed on the lowermost
branches, while higher up they are deeply cut. Yet, in spite of the many
modifications that leaves undergo, the leaves of any one species have
certain rather constant characters which are found in all forms, and the
student will have little difficulty in selecting and recognizing typical
leaves.

[Illustration: III. LEAF MARGINS

Serrate. Doubly Serrate. Crenate. Undulate. Sinuate. Lobed. Dentate.]

Leaves are either persistent, as in most of our conifers, which stay
green all winter, or they turn various colors with the frost and fall
early in autumn; often they hang dead and lifeless far into the winter.
The points about leaves which we are accustomed to consider are the
position or arrangement of the leaves on the branch, whether simple or
compound, size, shape, texture, color, amount and character of
pubescence, character of the margin, venation, etc. The following
diagrams will serve to illustrate some of the ordinary forms and shapes
of leaves, their margins, etc.

[Illustration: IV. PARTS OF A FLOWER

Perfect Flower. Stamen. Pistil.

a. Sepal (Calyx). b. Petal (Corolla). c. Stamen. d. Pistil. e. Anther.
f. Filament. g. Stigma. h. Style. i. Ovary.]

FLOWERS.--Every tree when old enough bears flowers in its proper season.
Some of these, as the Catalpas, Locusts and Horse-chestnuts are very
showy, others, like the Oaks and Hickories, are comparatively
inconspicuous; some are brilliantly colored, others are of the same
color as the leaves. Nevertheless, the flowers are very accurate means
of classification, and their only drawback is that they last for such a
short period of time each year.

[Illustration: V. TYPES OF INFLORESCENCES

Spike. Raceme. Panicle. Corymb. Umbel. Cyme.]

Just as we have male and female in the animal world, so we have male and
female in the plant world. A few of our trees, as the Locust, Basswood
and Cherries have perfect flowers, bearing both stamens and pistil. The
great majority, however, have unisexual flowers, bearing stamens or
pistils, but not both. When both male and female flowers are found on
the same tree, the flowers are said to be monoecious, and when male
flowers occur on one tree and the female on a different tree, the
flowers are said to be dioecious. The Cottonwood is dioecious, and the
little seeds are surrounded by a tuft of long, white hairs which enables
the wind to carry them to considerable distances from the parent tree,
to the disgust of people living within range. Many cities forbid the
planting of Cottonwood on account of the "cotton." Since in some cases
it is desirable to plant this rapid-growing tree, as in cities burning
large amounts of soft coal, it is a distinct advantage to know that male
trees are lacking in the objectionable "cotton" and may be planted
safely.

Before trees can produce fruit their flowers must be fertilized, i.e.,
pollen from the anther of a stamen must come in contact with the stigma
of a pistil. Some flowers are self-fertilized, others are
cross-fertilized. For a long time it was not known how fertilization was
accomplished, but now we know that many insects, like the nectar-loving
bees and butterflies, and in other cases the wind transport the pollen
from one flower to another, often miles being traversed before the right
kind of flower or a flower in the right stage of development is found.
And many are the modifications of flowers to insure this transference of
pollen.

FRUIT.--So numerous and so varied are the forms of tree fruits that it
would only be confusing to enumerate their various characters. Some
fruits, as the achenes of the Poplars and Willows, are so small and
light that they are carried long distances by the wind; others, like the
hickory nuts and walnuts, are too heavy to be wind-blown. Many fruits
are of considerable economic and commercial importance and are gathered
and marketed on a large scale; such are the hickory nuts, walnuts,
chestnuts, etc. Some, not esteemed by man, form an important article of
diet for the birds and small animals of the forest. Unfortunately, there
are a number of limitations to the usefulness of fruit for
identification purposes. Some trees require years to mature their fruit.
Many trees, while producing an abundance of fruit at certain intervals,
bear none at all or only very small and uncertain quantities between the
years of abundance. Again, in the case of dioecious trees, only the
female or pistillate bear fruit. Notwithstanding these limitations tree
fruits are a very valuable aid to the student, and he should always
search closely for evidences of their presence and character.

[Illustration: VI. WINTER TWIG OF RED MULBERRY

a. Tip-scar. b. Lateral bud. c. Leaf-scar. d. Stipule-scars.]

WINTER-BUDS.--Buds, with their accompanying leaf-and stipule-scars form
the basis of tree identification in winter. The size, color, position
with reference to the twig, number and arrangement and character of
bud-scales, etc., are all characters of the greatest value in winter
determinations. Buds are either terminal or lateral, depending on their
position on the twig. A lateral bud is one situated on the side of a
twig in the axil of a leaf-scar. A terminal bud is one situated at the
end of a twig, where it is ready to continue the growth of the twig the
following spring. In the keys an important consideration is the presence
or absence of the terminal bud. Inasmuch as the determination of this
point gives the beginner some trouble at first, it is hoped that the
accompanying diagrams and explanatory remarks will make the distinction
clear.

[Illustration: VII. WINTER TWIG OF BLACK WALNUT

   a. Terminal bud.
   b. Lateral bud.
   c. Leaf-scar.
   d. Bundle-scars.
   e. Pith.]

In the Elms, Willows, Basswood and many other species the terminal bud
and a small portion of the tip of the twig dies and drops off in late
autumn, leaving a small scar at the end of the twig (a, fig. VI). The
presence of this tip-scar indicates that the terminal bud is absent.
Often a lateral bud will be found very close to the tip-scar (b, fig.
VI), which, bending into line with the twig, makes it appear terminal.
However, the presence of a leaf-scar immediately below it shows it to be
a lateral bud (c, fig. VI). In some large twigs the eye unaided will
serve to find the tip-scar, but with the smaller twigs a hand-lens is
necessary.

The arrangement, size and shape of the leaf-scars (c, fig. VII) are
important factors in identification by winter characters. Within the
leaf-scars are one or more dots (d, fig. VII), sometimes quite
inconspicuous, often very prominent. These are the scars left by the
fibro-vascular bundles which run through the petiole into the blade of
the leaf, and are designated as bundle-scars. There may be only one as
in Sassafras and Hackberry, two as in Ginkgo, three as in the Poplars
and Cherries, or many; and they may be arranged in a U- or V-shaped line,
or they may be without definite order. Often stipule-scars (d, fig. VI)
occur on either side of the leaf-scar; these are scars left by the fall
of a pair of small leaflets called stipules and located at the base of
the leaves, and their form varies according to the form of the stipules
which made them.

BARK.--The woodsman uses the bark of a tree more than any other character
in distinguishing the trees about him, and he is often able to use this
character alone with much accuracy at great distances. However, the
appearance of bark differs so greatly with the age of the tree and with
its environment that it is difficult to describe it accurately. Some
characters are distinctive, however, and serve as a ready means of
identification; such characters are the peeling of the Sycamore and
Paper Birch, the "shagging" of the Shagbark Hickory, the spicy taste of
Sassafras bark and the mucilaginous inner bark of the Slippery Elm.

WOOD.--It is not expected that the information given under this heading
will be of any particular value in identifying living trees. Often,
however, the student finds himself in the midst of felling operations,
when the information concerning the wood is of considerable value.

DISTRIBUTION AND HABITAT.--To a lesser extent do distribution and habitat
of a species aid in the identification of a tree. It is a distinct aid
to know that the Chestnut is native in south-eastern Michigan only and
that the Mountain Ash does not extend south of Ludington. So too,
knowing the water-loving habit of the Swamp White Oak, we would not
expect to find this same tree flourishing on the top of a hard, dry
hill.

The characters, then, which are used to identify the trees about us are
many. Not all will be available at any one time, not all have been
mentioned in the foregoing pages nor in the manual. It is our opinion,
however, that the student will not be greatly handicapped by this lack
of detail, but rather that he will take great interest and genuine
pleasure in discovering these things for himself.


ARTIFICIAL KEYS, HOW MADE AND USED

An artificial key is a scheme for easily and quickly identifying any
unknown object under consideration. This bulletin being devoted to the
trees of Michigan, the keys to be found herein are intended to make it
possible for any person, even if his botanical training be meager, to
determine what trees grow about any home or farm, city park or woodlot
in the state. With certain modifications and limitations they may prove
useful in other localities as well. Since many people are unfamiliar
with the construction and use of keys for identification, it will be the
purpose of the following paragraphs to briefly outline the principles of
construction and the manner of using the keys to be found here.

The keys are based on the most striking similarities and differences
which the various parts of trees--twigs, buds, leaves, etc.--show, i. e.,
those characters which stand out in bold relief, which catch the eye at
first sight. Two alternatives are presented, either a character _is_ or
_is not_ present; these are the only choices possible. Indeed, further
divisions are unnecessary and only lead to confusion and possible
oversight. The two diametrically opposed characters are said to be
coördinate in rank. In the keys they are preceded by the same letter or
letters (_a_ and _aa_ or _b_ and _bb,_ etc.) and are set at the same
distance from the left margin of the page. Often _a_ and _aa,_ or _b_
and _bb_ are further divisible into other groups; in every case the
characters are opposed (a positive and a negative) and are given
coördinate rank. It is desirable for mechanical reasons to divide the
main divisions of the key more or less evenly, but this is not always
feasible, nor should it be religiously adhered to.

Suppose as a concrete example that it is desired to construct a key to
distinguish five houses in a city block. Three of these are of wood
construction, two are of brick, and of the two wooden houses one is
painted white and one brown. We may classify them as follows:

   a. Houses wood.

   b. Body paint brown. _Smith's house_
   bb. Body paint white.

   c. Trimmings green color. _Jones' house_
   cc. Trimmings slate color. _Brown's house_

   aa. Houses brick.

   b. Roof gray slate. _Johnson's house_
   bb. Roof red tile. _Public Library_

It is desirable in many cases to add other characters to lessen the
liability of confusion, where the characters chosen are not distinct,
and to show the user that he is on the right track. Thus, in the example
just given, green color and slate color under certain defects of the
eye, a coating of dust or deficiencies of the light might be confused,
under which circumstances we would be justified in adding to the above
statements without the criticism of description being made. Thus:

   bb.
   c. Trimmings green color; gable roof. _Jones' house_
   cc. Trimmings slate color; mansard roof. _Brown's house_

The keys in this bulletin are constructed on the above principles. They
are not in all cases as simple as the illustration just used, but if the
reader has mastered the house illustration he will have little or no
trouble with the larger keys. Suppose that (during a summer stroll) you
come across a large tree with rough, hard bark and thin, lobed leaves
which you do not know. Turning to the _Summer Key to the Genera_ you
find first _a. Leaves simple_, and contrasted with this _aa. Leaves
compound._ Obviously the leaf is simple and the genus sought lies in
that portion of the key preceding _aa_, i.e., under _a._ _b_ and _bb_
under _a_ give you a choice between _Leaves needle-shaped_,
_awl-shaped_, _strap-shaped_ or _scale-like_ and _Leaves broad and
flat_. The leaf being broad and flat you pass to _c_ and _cc_ under
_bb_. Here you have a choice between _Leaves alternate or clustered_ and
_Leaves opposite or whorled_. Inspection shows the arrangement to be
opposite, and you know that the genus sought lies in that portion of the
key between _cc_ and _aa_. Passing to _d_ and _dd_ under _cc_ gives the
choice between _Margin of leaves entire or only slightly undulate_ and
_Margin of leaves serrate to lobed_. The leaf is deeply lobed. It is
then either a _Viburnum_ or an _Acer_, and the fact that the leaf-margin
is lobed and not finely serrate brings the chase down to _Acer_. Before
going further go back over the key and make careful note of the
particular characters which were used to separate this genus from the
other genera and try to fix these in mind. This done, turn to the page
indicated, where you will find a _Summer Key to the Species of Acer_.
You run through this key in the same manner that you did the genus key.
If you have been careful in your search you will finally stop at _Acer
saccharum_. Once more pause and go back over this key and try to fix in
mind the characters which were used to separate the various species,
especially the difference between your tree and _Acer platanoides_,
which it so closely resembles. This done, turn to the page indicated and
compare the characters of your tree with the drawings and descriptions.
If you are satisfied with your diagnosis, well and good. If you find
that you are wrong, go over the keys again and find wherein you were led
astray.

Before you leave the tree take a sample of leaf properly labeled which
you can press between the pages of an old magazine and save for future
reference. Do this with other trees which you may find and when you get
home lay them out side by side so that the labels will not show and
compare them. A few trials of this kind will serve to form a mental
picture of each leaf which you will remember.

A very helpful practice for the beginner is that of making keys based
upon various characters. Practice keys of this kind will bring out the
differences and likenesses of trees as will no other means, and
characters which have hitherto escaped the eye will be prominently
brought forward. Nor should the student take his characters from books,
but rather should he go to the woods and get his knowledge first hand.

It is hardly necessary to state that the key is a valuable crutch while
learning to walk, but once the leg is strong enough to bear the weight
it should be discarded, lest it become a burden. A key has for its main
object the guidance of the student through the preliminary steps leading
to a more intimate knowledge of the trees. When once he knows a tree,
instinctively, because of long acquaintance with it, just as he knows
people, then the need for a key will have ceased.


SUMMER KEY TO THE GENERA[A]

   a. Leaves simple.

   b. Leaves needle-shaped, awl-shaped, strap-shaped or
   scale-like.

   c. Leaves in clusters of 2-many.

   d. Leaves in clusters of 2-5, sheathed, persistent for several
   years. PINUS, p. 4.

   dd. Leaves in fascicles of 8-many, on short, lateral
   branchlets, deciduous in autumn. LARIX, p. 17.

   cc. Leaves solitary, not clustered.

   d. Leaves opposite.

   e. Twigs flattened; leaves all of one kind, scale-like,
   decurrent on the stem; fruit a small, pale brown cone. THUJA,
   p. 31.

   ee. Twigs essentially terete; leaves of two kinds, either
   scale-like, or else awl-shaped, often both kinds on the same
   branch, not decurrent on the stem; fruit berry-like, bluish.
   JUNIPERUS, p. 33.

   dd. Leaves alternate or spirally-whorled.

   e. Leaves flattened, soft to the touch.

   f. Leaves 1/2-1-1/4 inches long, sessile, aromatic; cones 2-4
   inches long; bark of trunk with raised blisters containing
   resin. ABIES, p. 27.

   ff. Leaves seldom over 1/2 inch long, short-petioled, not
   aromatic; cones about 3/4 inch long; bark of trunk without
   raised blisters. TSUGA, p. 29.

   ee. Leaves 4-sided, harsh to the touch. PICEA, p. 18.

   bb. Leaves broad and flat.

   c. Leaves alternate or clustered, never opposite nor whorled.

   d. Margin of leaves entire or only slightly undulate.

   e. Leaves heart-shaped or rounded; fruit a legume. CERCIS, p.
   167.

   ee. Leaves oval, ovate or obovate; fruit not a legume.

   f. Branches armed with stout, straight spines; fruit large,
   orange-like. MACLURA, p. 133.

   ff. Branches without spines; fruit small, not orange-like.

   g. Fruit an acorn. QUERCUS, p. 96.

   gg. Fruit a drupe or berry.

   h. Twigs spicy-aromatic when bruised; leaves of many shapes on
   the same branch. SASSAFRAS, p. 139.

   hh. Twigs not spicy-aromatic; leaves not of many shapes on the
   same branch.

   i. Leaves thick, abruptly pointed, very lustrous above, not
   clustered at the ends of the branches. NYSSA, p. 209.

   ii. Leaves thin, long-pointed, not lustrous above, clustered
   at the ends of the branches. CORNUS, p. 202.

   dd. Margin of leaves serrate, toothed or lobed.

   e. Margin of leaves serrate to toothed.

   f. Branches armed with stiff, sharp thorns. CRATAEGUS, p. 151.

   ff. Branches not armed.

   g. Base of leaves decidedly oblique.

   h. Leaf-blades about as long as they are broad, heart-shaped.
   TILIA, p. 201.

   hh. Leaf-blades 1-1/2 - 2 times as long as they are broad, oval
   to ovate.

   i. Leaves thin, coarsely but singly serrate; fruit a globular
   drupe, ripe in autumn. CELTIS, p. 131.

   ii; Leaves thick, coarsely and doubly serrate; fruit a samara,
   ripe in spring. ULMUS, p. 122.

   gg. Base of leaves essentially symmetrical.

   h. Teeth coarse, 2-5 per inch of margin.

   i. Leaves very glabrous both sides; fruit a prickly bur.

   j. Leaves 3-5 inches long, very lustrous beneath; bark close,
   smooth, steel-gray. FAGUS, p. 93.

   jj. Leaves 6-8 inches long, not lustrous beneath; bark
   fissured, brownish. CASTANEA, p. 95.

   ii. Leaves pubescent or white-tomentose, at least beneath;
   fruit not a prickly bur.

   j. Leaves 2-4 inches long, broadly ovate to suborbicular;
   fruit a very small capsule, falling in spring. POPULUS, p. 44.

   jj. Leaves 4-7 inches long, oblong-lanceolate to obovate;
   fruit an acorn, falling in autumn. QUERCUS, p. 96.

   hh. Teeth fine, 6-many per inch of margin.

   i. Leaf-petioles laterally compressed; leaves tremulous.
   POPULUS, p. 44.

   ii. Leaf-petioles terete; leaves not tremulous.

   j. Leaf-blades at least 3 times as long as they are broad.

   k. Twigs brittle; fruit a very small capsule, falling in
   spring. SALIX, p. 34.

   kk. Twigs tough; fruit a fleshy drupe, falling in late summer
   or autumn. PRUNUS, p. 152.

   jj. Leaf-blades not more than twice as long as they are broad.

   k. Leaf-blades about twice as long as they are broad.

   l. Margin of leaves singly serrate; fruit fleshy.

   m. Lenticels conspicuous; pith whitish or brownish; bark
   easily peeled off in papery layers; buds ovoid. PRUNUS, p.
   152.

   mm. Lenticels inconspicuous; pith greenish; bark not separable
   into papery layers; buds narrow-conical. AMELANCHIER, p. 149.

   ll. Margin of leaves doubly serrate; fruit not fleshy.

   m. Trunk fluted; fruit inclosed within a halberd-shaped
   involucre. CARPINUS, p. 83.

   mm. Trunk not fluted; fruit not inclosed within a
   halberd-shaped involucre.

   n. Bark of trunk gray-brown, broken into narrow, flattish
   pieces loose at the ends; fruit in hop-like strobiles. OSTRYA,
   p. 81.

   nn. Bark of trunk white, yellow or dark brown, platy or
   cleaving off in papery layers; fruit not in hop-like
   strobiles. BETULA, p. 84.

   kk. Leaf-blades almost as broad as they are long.

   l. Lower side of leaves more or less downy; sap milky; leaves
   not crowded on short, spur-like branchlets; fruit berry-like,
   black. MORUS, p. 135.

   ll. Lower side of leaves glabrous; sap not milky; leaves
   crowded on short, spur-like branchlets; fruit a large, green
   pome. PYRUS, p. 142.

   ee. Margin of leaves distinctly lobed.

   f. Fruit an acorn. QUERCUS, p.96.

   ff. Fruit not an acorn.

   g. Leaves fan-shaped, with many fine veins radiating from the
   base of the blade. GINKGO, p. 3.

   gg. Leaves not fan-shaped, without many fine veins radiating
   from the base of the blade.

   h. Leaf-lobes entire.

   i. Leaf-petioles 5-6 inches long; leaves lustrous above; twigs
   not aromatic when bruised. LIRIODENDRON, p. 137.

   ii. Leaf-petioles about 1 inch long; leaves dull above; twigs
   spicy-aromatic when bruised. SASSAFRAS, p. 139.

   hh. Leaf-lobes sinuate-toothed to serrate.

   i. Leaf-lobes coarsely sinuate-toothed. PLATANUS, p. 141.

   ii. Leaf-lobes serrate.

   j. Branches armed with stiff, sharp thorns; sap not milky.
   CRATAEGUS, p. 151.

   jj. Branches unarmed; sap milky. MORUS, p. 135.

   cc. Leaves opposite or whorled.

   d. Margin of leaves entire or only slightly undulate.

   e. Leaves 3-5 inches long; spray fine; fruit an ovoid, scarlet
   drupe. CORNUS, p. 202.

   ee. Leaves 5-12 inches long; spray coarse; fruit a long,
   slender-cylindrical capsule. CATALPA, p. 222.

   dd. Margin of leaves serrate to lobed.

   e. Margin of leaves finely serrate. VIBURNUM, p. 229.

   ee. Margin of leaves distinctly lobed. ACER, p. 172.

   aa. Leaves compound.

   b. Leaves alternate.

   c. Leaves simple-pinnate.

   d. Branchlets armed with short, sharp prickles. ROBINIA, p.
   169.

   dd. Branchlets unarmed.

   e. Leaflets entire with the exception of 2 or more coarse,
   glandular teeth at the base. AILANTHUS, p. 171.

   ee. Leaflets serrate the entire length.

   f. Upper leaflets less than 1 inch broad.

   g. Trunk and large branches armed with stout spines; leaflets
   3/4-1-1/2 inches long. GLEDITSIA, p. 165.

   gg. Trunk and large branches unarmed; leaflets 2-3 inches
   long. PYRUS, p. 142.

   ff. Upper leaflets 1-5 inches broad.

   g. Leaflets 5-11; pith homogeneous. CARYA, p. 66.

   gg. Leaflets 11-23; pith chambered. JUGLANS, p. 60.

   cc. Leaves bi-pinnate.

   d. Trunk and large branches armed with stout spines; leaflets
   3/4 - 1-1/2 inches long, GLEDITSIA, p. 165.

   dd. Trunk and large branches unarmed; leaflets 2 - 2-1/2
   inches long. GYMNOCLADUS, p. 163.

   bb. Leaves opposite.

   c. Leaves pinnately compound; fruit a samara.

   d. Leaflets 3-5; samaras paired. ACER, p. 172.

   dd. Leaflets 7-11, exceptionally 5; samaras not paired.
   FRAXINUS, p. 210.

   cc. Leaves digitately compound; fruit a prickly bur. AESCULUS,
   p. 194.


WINTER KEY TO THE GENERA[B]

   a. Leaves persistent and green throughout the winter,
   needle-shaped, awl-shaped or scale-like.

   b. Leaves in clusters of 2-5, sheathed. PINUS, p. 5.

   bb. Leaves solitary, not clustered.

   c. Leaves opposite.

   d. Twigs flattened; leaves all of one kind, scale-like,
   decurrent on the stem; fruit a small, pale brown cone. THUJA,
   p. 31.

   dd. Twigs essentially terete; leaves of two kinds, either
   scale-like, or else awl-shaped, often both kinds on the same
   branch, not decurrent on the stem; fruit berry-like, bluish.
   JUNIPERUS, p. 33.

   cc. Leaves alternate or spirally-whorled.

   d. Leaves flattened, soft to the touch.

   e. Leaves 1/2 - 1-1/4 inches long, sessile, aromatic; cones
   2-4 inches long; bark of trunk with raised blisters containing
   resin. ABIES, p. 27.

   ee. Leaves seldom over 1/2 inch long, short-petioled, not
   aromatic; cones about 3/4 inch long; bark of trunk without
   raised blisters. TSUGA, p. 29.

   dd. Leaves 4-sided, harsh to the touch. PICEA, p. 19.

   aa. Leaves not persistent and green throughout the winter, but
   deciduous in early autumn.

   b. Twigs, branches or trunks armed with stiff, sharp prickles,
   spines or thorns.

   c. Thorns or spines not exceeding 1/2 inch in length on the
   branches.

   d. Spines in pairs at each node; buds rusty-hairy, 3-4
   superposed; fruit a flat pod. ROBINIA, p. 169.

   dd. Spines one at each node; buds glabrous, not superposed;
   fruit orange-like. MACLURA, p. 133.

   cc. Thorns or spines much exceeding 1/2 inch in length on the
   branches.

   d. Thorns usually branched, situated above the nodes; lateral
   buds superposed, the lower covered by bark; fruit a flat pod.
   GLEDITSIA, p. 165.

   dd. Thorns unbranched on twigs, situated at the nodes; lateral
   buds not superposed, not covered by bark; fruit a small pome.
   CRATAEGUS, p. 151.

   bb. Twigs, branches or trunks unarmed.

   c. Leaf-scars mainly crowded on short, stout, lateral shoots.

   d. Bundle-scar 1; fruit a cone, usually present. LARIX, p. 17.

   dd. Bundle-scars 2; fruit a globose drupe falling in autumn.
   GINKGO, p. 3.

   cc. Leaf-scars distributed along the lateral branches.

   d. Leaf-scars (or some of them) 3 at a node, i. e., whorled.
   CATALPA, p. 223.

   dd. Leaf-scars 1-2 at a node, i.e., not whorled.

   e. Leaf-scars 2 at a node, i.e., opposite.

   f. Terminal buds 1/2 - 1-1/2 inches long, resin-coated; twigs
   very stout. AESCULUS, p. 195.

   ff. Terminal buds rarely exceeding 1/2 inch in length, not
   resin-coated; twigs not conspicuously stout.

   g. Leaf buds with 1 pair of scales visible.

   h. Buds scurfy-pubescent. VIBURNUM, p. 229.

   hh. Buds glabrous. CORNUS, p. 203.

   gg. Leaf buds with 2 or more pairs of scales visible.

   h. Bundle-scars usually 3, distinct, separated. ACER, p. 174.

   hh. Bundle-scars many, minute, more or less confluent in a
   U-shaped line. FRAXINUS, p. 211.

   ee. Leaf-scars 1 at a node, i.e., alternate.

   f. Bundle-scars 1-3.

   g. Bundle-scar only 1, or appearing as 1.

   h. Twigs bright green, spicy-aromatic; bundle-scar appearing
   as a horizontal line; terminal bud present; pith homogeneous.
   SASSAFRAS, p. 139.

   hh. Twigs brownish, not spicy-aromatic; bundle-scar appearing
   as a large dot; terminal bud absent; pith chambered. CELTIS,
   p. 131.

   gg. Bundle-scars 3 or in 3 compound, but distinct groups.

   h. Terminal bud present.

   i. Stipule-scars present.

   j. First scale of lateral bud directly in front, i.e., exactly
   above the center of the leaf-scar; twigs brittle; pith
   somewhat star-shaped in cross-section. POPULUS, p. 45.

   jj. First scale of lateral bud not directly in front, i. e.,
   to one side of the center of the leaf-scar; twigs not brittle;
   pith circular in cross-section. PRUNUS, p. 153.

   ii. Stipule-scars absent.

   j. Buds bright to dark red, the terminal 1/8 - 1/4 inch long.

   k. Branches contorted, bearing many short, spur-like
   branchlets; fruit an apple an inch or more in diameter, light
   green. PYRUS, p. 143.

   kk. Branches not contorted, not bearing short, spur-like
   branchlets; fruit berry-like, 1/2 inch long, blue-black.
   NYSSA, p. 209.

   jj. Buds brownish to gray, the terminal exceeding 1/4 inch in
   length.

   k. Buds narrow-conical, sharp-pointed; leaf-scars small,
   narrowly crescent-shaped; twigs about 1/16 inch thick; pith
   homogeneous; fruit berry-like, not present. AMELANCHIER, p.
   149.

   kk. Buds broadly conical to ovoid, blunt-pointed; leaf-scars
   conspicuous, broadly heart-shaped; twigs about 1/4 inch thick;
   pith chambered; fruit a nut, often present. JUGLANS, p. 61.

   hh. Terminal bud absent (sometimes present on short shoots of
   _Betula_).

   i. Stipule-scars present.

   j. Bud-scale only 1 visible; twigs brittle. SALIX; p. 34.

   jj. Bud-scales 2 or more; twigs not brittle.

   k. Bark smooth, close, warty or peeling into papery layers,
   but not flaky nor rough-ridged.

   l. Tip of bud appressed; fruit berry-like. CELTIS, p. 131.

   ll. Tip of bud not appressed; fruit not berry-like.

   m. Trunk fluted; catkins not present in winter; lenticels not
   elongated horizontally; low tree or bushy shrub. CARPINUS, p.
   83.

   mm. Trunk not fluted; catkins usually present in winter;
   lenticels elongated horizontally; large trees. BETULA, p. 85.

   kk. Bark flaky or rough-ridged, not warty nor peeling off in
   papery layers.

   l. Bundle-scars depressed, conspicuous; bark thick, more or
   less deeply furrowed. ULMUS, p. 123.

   ll. Bundle-scars not depressed, inconspicuous; bark thin,
   broken into narrow, flattish strips, loose at the ends.
   OSTRYA, p. 81.

   ii. Stipule-scars absent.

   j. Buds silky-pubescent, depressed; twigs stout, clumsy,
   blunt, with conspicuous leaf-scars. GYMNOCLADUS, p. 163.

   jj. Buds glabrous, not depressed; twigs slender, with
   inconspicuous leaf-scars.

   k. Buds 1/8 inch long, obtuse, somewhat flattened and
   appressed; pith with reddish longitudinal streaks. CERCIS, p.
   167.

   kk. Buds 1/8-1/4 inch long, acute, not flattened nor
   appressed; pith without reddish streaks. PRUNUS, p. 153.

   ff. Bundle-scars 4-many.

   g. Bundle-scars in a single U-shaped line.

   h. Terminal bud present; fruit berry-like; a shrub or small
   tree. PYRUS, p. 143.

   hh. Terminal bud absent; fruit not berry-like; large trees.

   i. Stipule-scars present; twigs slender.

   j. Stipule-scars encircling the twig; leaf-scars nearly
   surrounding the bud; bark peeling off in thin plates, exposing
   the lighter colored inner bark. PLATANUS, p. 141.

   jj. Stipule-scars not encircling the twig; leaf-scars not
   nearly surrounding the bud; bark thick, rough-ridged, not
   exposing the inner bark. ULMUS, p. 123.

   ii. Stipule-scars absent; twigs very stout.

   j. Bundle-scars usually not more than 5. GYMNOCLADUS, p. 163.

   jj. Bundle-scars usually 6-12. AILANTHUS, p. 171.

   gg. Bundle-scars variously grouped or scattered, but not in a
   single line.

   h. Terminal bud present.

   i. Stipule-scars present.

   j. Stipule-scars encircling the twig; visible bud-scales 2,
   united. LIRIODENDRON, p. 137.

   jj. Stipule-scars not encircling the twig; visible bud-scales
   more than 2, not united.

   k. Buds 4 times as long as broad, not clustered at the tips of
   vigorous shoots; fruit a prickly bur. FAGUS, p. 93.

   kk. Buds not 4 times as long as broad, usually clustered at
   the tips of vigorous shoots; fruit an acorn. QUERCUS, p. 98.

   ii. Stipule-scars absent. CARYA, p. 67.

   h. Terminal bud absent (occasionally present in _Castanea_).

   i. Bud at end of twig very obliquely unsymmetrical,
   mucilaginous when chewed. TILIA, p. 201.

   ii. Bud at end of twig symmetrical, not mucilaginous when
   chewed.

   j. Bud-scales 2-3 visible; pith star-shaped in cross-section;
   sap not milky; fruit a prickly bur, present; large tree.
   CASTANEA, p. 95.

   jj. Bud-scales 4-8 visible; pith not star-shaped in
   cross-section; sap milky; fruit berry-like, not present; small
   tree. MORUS, p. 135.




MANUAL OF TREES


DESCRIPTION OF SPECIES

WITH

SUMMER AND WINTER KEYS

TO THE SPECIES

[Illustration: +Ginkgo. Maidenhair Tree+

   1. Winter twig, × 1/2.
   2. Leaf, × 1/2.
   3. Staminate flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1.]

+GINKGOACEAE+

+Ginkgo.[C] Maidenhair Tree+

_Ginkgo biloba L._ [_Salisburia adiantifolia Smith_]


HABIT.--A slender tree in youth, with slender, upright branches, becoming
broader with age and forming a symmetrical, pyramidal crown; probably
60-80 feet high, with a trunk diameter of 2-4 feet.

LEAVES.--Clustered at the ends of short, spur-like shoots, or scattered
alternately on the long terminal branches; simple; 2-5 inches broad;
more or less fan-shaped; usually bilobed and irregularly crenate at the
upper extremity; thin and leathery; glabrous, pale yellow-green on both
sides; petioles long, slender; turning a clear, golden yellow before
falling in autumn.

FLOWERS.--May, with the leaves; dioecious; the staminate in
short-stalked, pendulous catkins, 1 to 1-1/2 inches long, yellow; the
pistillate more or less erect on the shoot, long-stalked, consisting of
2 naked ovules, one of which usually aborts.

FRUIT.--Autumn; a more or less globose drupe, orange-yellow to green,
about 1 inch in diameter, consisting of an acrid, foul-smelling pulp
inclosing a smooth, whitish, somewhat flattened, almond-flavored nut.

WINTER-BUDS.--Terminal bud about 1/8 inch long, conical, smooth, light
chestnut-brown; lateral buds divergent, usually only on rapid-growing
shoots.

BARK.--Twigs gray-brown and smooth; thick, ash-gray and somewhat
roughened on the trunk, becoming more or less fissured in old age.

WOOD.--Light, soft, weak, close-grained, yellow-white to light red-brown,
with thin, lighter colored sapwood.

NOTES.--Origin in dispute, but probably a native of northern China.
Extensively cultivated in China and Japan, where its fruit is esteemed.
Easily propagated from seed. Thrives in deep, well-drained, rich soil.
Practically free from insect and fungous attacks, and little harmed by
the smoke of cities. Probably hardy throughout the southern half of the
Lower Peninsula.


+SUMMER KEY TO THE SPECIES OF PINUS+

   a. Leaves 5 in a cluster; cones 4-10 inches long. _P.
   strobus_, p. 7.

   aa. Leaves 2 in a cluster; cones less than 4 inches long.

   b. Leaves 1-3 inches long.

   c. Leaves about 1 inch long, divergent; cones sessile,
   pointing forward towards the tip of the branch, persistent
   10-15 years, opening very unevenly. _P. banksiana_, p. 9.

   cc. Leaves 1-1/2-3 inches long, slightly divergent; cones
   stout-stalked, pointing away from the tip of the branch,
   maturing in second season, opening evenly. _P. sylvestris_, p.
   13.

   bb. Leaves 3-6 inches long.

   c. Bark of trunk red-brown; cones maturing in second season,
   about 2 inches long; cone-scales thickened at the apex, but
   unarmed. _P. resinosa_, p. 15.

   cc. Bark of trunk gray to nearly black; cones maturing in
   first season, 2-3 inches long; cone-scales thickened at the
   apex and topped with a short spine. _P. laricio austriaca_, p.
   11.


+WINTER KEY TO THE SPECIES OF PINUS+

   a. Leaves 5 in a cluster; cones 4-10 inches long. _P. strobus_,
   p. 7.

   aa. Leaves 2 in a cluster; cones less than 4 inches long.

   b. Leaves 1-3 inches long.

   c. Leaves about 1 inch long, divergent; cones sessile,
   pointing forward towards the tip of the branch, persistent
   10-15 years, opening very unevenly. _P. banksiana_, p. 9.

   cc. Leaves 1-1/2-3 inches long, slightly divergent; cones
   stout-stalked, pointing away from the tip of the branch,
   maturing in second season, opening evenly. _P. sylvestris_, p.
   13.

   bb. Leaves 3-6 inches long.

   c. Bark of trunk red-brown; cones maturing in second season,
   about 2 inches long; cone-scales thickened at the apex, but
   unarmed. _P. resinosa_, p. 15.

   cc. Bark of trunk gray to nearly black; cones maturing in
   first season, 2-3 inches long; cone-scales thickened at the
   apex and topped with a short spine. _P. laricio austriaca_, p.
   11.


[Illustration: +White Pine+

   1. Cluster of leaves, × 1.
   2. Cross-sections of leaves, enlarged.
   3. Partly opened cone, × 3/4.
   4. Cone-scale with seeds, × 1.]


+PINACEAE+

+White Pine+

_Pinus strobus L._


HABIT.--A large tree 60-80 feet high, with a trunk diameter of 2-4 feet;
forming a wide, pyramidal crown. Formerly trees 100-150 feet in height
and 5-7 feet in trunk diameter were not exceptional.

LEAVES.--In clusters of five; 3-5 inches long; slender, straight,
needle-shaped, 3-sided, mucronate; pale blue-green. Persistent about 2
years.

FLOWERS.--June; monoecious; the staminate oval, light brown, about 1/3
inch long, surrounded by 6-8 involucral bracts; the pistillate
cylindrical, about 1/4 inch long, pinkish purple, long-stalked.

FRUIT.--Autumn of second season, falling during the winter and succeeding
spring; pendent, short-stalked, narrow-cylindrical, often curved,
greenish cones, 4-10 inches long; scales rather loose, slightly
thickened at the apex; seeds red-brown, 1/4 inch long, with wings 1 inch
long.

WINTER-BUDS.--Oblong-ovoid, sharp-pointed, yellow-brown, 1/4-1/2 inch
long.

BARK.--Twigs at first rusty-tomentose, later smooth and light brown,
finally thin, smooth, greenish; thick, dark gray on the trunk, shallowly
fissured into broad, scaly ridges.

WOOD.--Light, soft, weak, compact, straight-grained, easily worked, light
brown, with thin, whitish sapwood.

DISTRIBUTION.--Upper Peninsula and Lower Peninsula north of Allegan,
Eaton and St. Clair Counties. Often planted as an ornamental tree
farther south.

HABITAT.--Prefers a light, fertile loam; sandy soils of granite origin.

NOTES.--Rapid of growth. Small seedlings easily transplanted. Formerly
very abundant, but rapidly nearing extinction through destructive
lumbering.


[Illustration: +Jack Pine. Scrub Pine+

   1. Cluster of leaves, × 1.
   2. Cross-section of leaf, enlarged.
   3. Branchlet with unopened cone, × 1.
   4. Branchlet with opened cone, × 1.
   5. Cone-scale with seeds, × 1.]


+PINACEAE+

+Jack Pine. Scrub Pine+

_Pinus banksiana Lamb._ [_Pinus divaricata (Ait.) Du Mont de Cours._]


HABIT.--Usually a small tree 20-30 feet high, with a trunk diameter of
8-12 inches; forming a crown varying from open and symmetrical to
scrubby, stunted, and variously distorted.

LEAVES.--In clusters of two; about 1 inch long; narrow-linear, with
sharp-pointed apex; stout, curved or twisted, divergent from a short
sheath; dark gray-green. Persistent 2-3 years.

FLOWERS.--May-June; monoecious; the staminate in oblong clusters 1/2 inch
long, composed of many sessile, yellow anthers imbricated upon a central
axis; the pistillate in subglobose clusters, composed of many
carpel-like, purple scales (subtended by small bracts) spirally arranged
upon a central axis.

FRUIT.--Autumn of second or third season, but remaining closed for
several years and persistent on the tree for 10-15 years; erect, usually
incurved, oblong-conical, sessile cones, 1-1/2-2 inches long; scales
thickened at the apex; seeds triangular, nearly black, 3/8 inch long,
with wings 1/3 inch long.

WINTER-BUDS.--Terminal bud 1/4 inch long, ovoid, rounded, pale brown;
lateral buds smaller.

BARK.--Twigs yellow-green, becoming purple, finally dark red-brown and
rough with the persistent bases of fallen leaves; thin, dark red-brown
on the trunk, with shallow, rounded ridges, rough-scaly on the surface.

WOOD.--Light, soft, weak, close-grained, light brown, with thick, whitish
sapwood.

DISTRIBUTION.--Common from Clare County northward; occurs sparingly along
the lake shore as far south as Grand Haven on the west and Port Austin
on the east.

HABITAT--Sandy, sterile soil.

NOTES.--Cones open unevenly. Slow of growth. Difficult to transplant.


[Illustration: +Austrian Pine. Black Pine+

   1. Cluster of leaves, × 1.
   2. Cross-section of leaf, enlarged.
   3. Unopened cone, × 1.
   4. Partly opened cone, × 1/2.
   5. Cone-scale with seeds, × 1.]


+PINACEAE+

+Austrian Pine. Black Pine+

_Pinus laricio austriaca Endl._ [_Pinus austriaca Höss._]


HABIT.--A large tree 60-80 feet high, with a trunk diameter of 2-4 feet;
forming a massive, spreading crown of stiff, strong branches.

LEAVES.--In clusters of two; 3-6 inches long; slender, rigid,
sharp-pointed, curved towards the twig; deep green on both faces.
Persistent 3-6 years.

FLOWERS.--May-June; monoecious; the staminate cylindrical, subsessile,
bright yellow, about 3/4 inch long; the pistillate cylindrical, small,
bright red, subsessile.

FRUIT.--Autumn of first season, opening two years after full size is
attained and remaining on the tree several years; erect, sessile,
long-ovoid cones 2-3 inches long; scales smooth, lustrous, thickened at
the apex and topped with a short spine in the center; seeds red-brown,
1/4 inch long, with wings 3/4 inch long.

WINTER-BUDS.--Oblong-conical, sharp-pointed, red-brown, resinous, about
1/2 inch long.

BARK.--Twigs brownish to olive-brown and smooth, becoming darker with
age; thick, gray to nearly black on old trunks and coarsely and deeply
fissured.

WOOD.--Light, strong, very resinous, red-brown, with thick, yellowish to
reddish white sapwood.

NOTES.--Perfectly hardy. Adapts itself to a variety of soils. Well
adapted for screens and wind-breaks. Easily transplanted when small.
Grows rapidly.


[Illustration: +Scotch Pine. Scotch Fir+

   1. Cluster of leaves, × 1.
   2. Cross-section of leaf, enlarged.
   3. Unopened cone, × 1.
   4. Partly opened cone, × 1.
   5. Cone-scale with seeds, × 1.]


+PINACEAE+

+Scotch Pine. Scotch Fir+

_Pinus sylvestris L._


HABIT.--A large tree 60-80 feet high, with a trunk diameter of 1-2 feet;
the side branches persist, forming a massive, wide-spreading crown.

LEAVES.--In clusters of two; 1-1/2-3 inches long; stiff, more or less
twisted, spreading slightly from a short sheath; bluish-or often
glaucous-green. Persistent 3-4 years.

FLOWERS.--May-June; monoecious; the staminate ovoid, short-stalked,
yellowish, about 1/4 inch long; the pistillate oblong, reddish,
short-stalked, about 1/4 inch long.

FRUIT.--Autumn of second season, falling as soon as ripe; pendent,
stout-stalked, ovoid-conical cones 1-1/2-2-1/2 inches long; scales dull
gray-brown, thickened at the apex into 4-sided, recurved points; seeds
red-brown, nearly 1/4 inch long, with wings about 3/4 inch long.

WINTER-BUDS.--Oblong-ovoid, sharp-pointed, red-brown, resinous, about 1/4
inch long.

BARK.--Twigs reddish to orange-brown, becoming grayish; thick, dark
orange-brown on old trunks and coarsely and deeply fissured.

WOOD.--Light, stiff, straight-grained, strong, heavy, hard, resinous,
red-brown, with thick, yellow to reddish white sapwood.

NOTES.--Very rapid of growth. Reaches perfection only in cold or elevated
regions. Adapts itself to a variety of soils. A valuable ornamental
tree. Very useful for screens or shelter belts.


[Illustration: +Red Pine, Norway Pine+

   1. Cluster of leaves, × 1.
   2. Cross-section of leaf, enlarged.
   3. Opened cone, × 1.
   4. Cone-scale with seeds, × 1.]


+PINACEAE+

+Red Pine. Norway Pine+

_Pinus resinosa Ait._


HABIT.--A large tree 70-80 feet high, with a trunk diameter of 2-3 feet;
stout, horizontal branches, form a broad, rounded, rather open crown.

LEAVES.--In clusters of two; 4-6 inches long; slender, straight,
needle-shaped, sharp-pointed, flexible, from elongated, persistent
sheaths; lustrous dark green. Persistent 4-5 years.

FLOWERS.--April-May; monoecious; the staminate in oblong, dense clusters,
1/2-3/4 inch long, composed of many sessile, purple anthers imbricated
upon a central axis; the pistillate single or few-clustered at the end
of the branchlets, subglobose; scales ovate, scarlet, borne on stout
peduncles covered with pale brown bracts.

FRUIT.--Autumn of second season, falling the next summer; ovoid-conical,
nearly sessile cones, about 2 inches long; scales thickened at the apex;
seeds oval, compressed, light mottled-brown, with wings 1/2-3/4 inch
long.

WINTER-BUDS.--About 3/4 inch long, ovoid or conical, acute, red-brown,
with rather loose scales.

BARK.--Twigs orange-brown, becoming rough with the persistent bases of
leaf-buds; thick and red-brown on the trunk, shallowly fissured into
broad, flat ridges.

WOOD.--Light, hard, very close-grained, pale red, with thin, yellow to
white sapwood.

DISTRIBUTION.--Very abundant in Clare County and northward; frequent on
the east side of the state as far south as Port Huron.

HABITAT.--Sandy plains and dry woods.

NOTES.--Rapid of growth on the better soils. Difficult to transplant.


[Illustration: +Tamarack+

   1. Autumn branchlet, with leaves and cones, × 1.
   2. Cross-section of leaf, enlarged.
   3. Fruiting branchlet in winter, × 1.
   4. Cone-scale with seeds, × 2.]


+PINACEAE+

+Tamarack+

_Larix laricina (DuRoi) Koch_ [_Larix americana Michx._]


HABIT.--A tree sometimes 80-100 feet high, with a trunk diameter of 1-2
feet; forming a broad, open, irregular crown of horizontal branches.

LEAVES.--Scattered singly along the leading shoots or clustered on the
short lateral branchlets; linear, with blunt apex; rounded above, keeled
beneath; about 1 inch long; bright green; sessile. Deciduous in early
autumn.

FLOWERS.--April-May, with the leaves, monoecious; the staminate sessile,
subglobose, yellow, composed of many short-stalked anthers spirally
arranged about a central axis; the pistillate oblong, short-stalked,
composed of orbicular, green scales (subtended by red bracts) spirally
arranged about a central axis.

FRUIT.--Autumn of first season, but persistent on the tree for a year
longer; ovoid, obtuse, light brown, short-stalked cones, 1/2-3/4 inch
long; seeds 1/8 inch long, with pale brown wings widest near the middle.

WINTER-BUDS.--Small, globose, lustrous, dark red.

BARK.--Twigs at first grayish, glaucous, later light orange-brown, and
finally dark brown; red-brown and scaly on the trunk.

WOOD.--Heavy, hard, very strong, coarse-grained, very durable, light
brown, with thin, nearly white sapwood.

DISTRIBUTION.--Common throughout the state.

HABITAT.--Prefers cold, deep swamps, or in the north coming out on the
drier uplands.

NOTES.--Becomes a picturesque tree in old age. Should be transplanted
while dormant.


+SUMMER KEY TO THE SPECIES OF PICEA+

   a. Leaves 3/4-1 inch long, sharp-pointed; twigs glabrous.

   b. Cones 1-2 inches long, maturing in first season; leaves
   ill-scented when bruised. _P. canadensis_, p. 21.

   bb. Cones 3-6 inches long, maturing in second season; leaves
   not ill-scented when bruised. _P. abies_, p. 25.

   aa. Leaves 1/8-3/8 inch long, blunt-pointed; twigs
   rusty-pubescent. _P. mariana_, p. 23.


+WINTER KEY TO THE SPECIES OF PICEA+

   a. Leaves 3/4-1 inch long, sharp pointed; twigs glabrous.

   b. Cones 1-2 inches long, maturing in first season; leaves
   ill-scented when bruised. _P. canadensis_, p. 21.

   bb. Cones 3-6 inches long, maturing in second season; leaves
   not ill-scented when bruised. _P. abies_, p. 25.

   aa. Leaves 1/8-3/8 inch long, blunt-pointed; twigs
   rusty-pubescent. _P. mariana_, p. 23.


[Illustration: +White Spruce+

   1. Winter branchlet, x.
   2. Leaves, × 1.
   3. Cross-section of leaf, enlarged.
   4. Unopened cone, × 1.
   5. Partly opened cone, × 1.
   6. Cone-scale with seeds, × 1.]


+PINACEAE+

+White Spruce+

_Picea canadensis (Mill.) BSP._ [_Picea alba Link_]


HABIT.--A tree 50-60 feet high, with a trunk diameter of 1-2 feet;
forming a rather broad, open, pyramidal crown.

LEAVES.--Spirally arranged, but crowded on the upper side of the branches
by the twisting of those on the under side; awl-shaped, 4-sided,
incurved; dark blue-green; about 3/4 inch long; ill-scented when
bruised. Persistent for several years.

FLOWERS.--April-May; monoecious; the staminate oblong-cylindrical,
long-stalked, 1/2-3/4 inch long, composed of many spirally arranged, red
anthers; the pistillate oblong-cylindrical, composed of broad, reddish
scales (subtended by orbicular bracts) spirally arranged upon a central
axis.

FRUIT.--Autumn or early winter of first season, falling soon after
discharging the seeds; pendent, slender, oblong-cylindrical, nearly
sessile cones, 1-2 inches long; seeds about 1/8 inch long, with large
wings oblique at the apex.

WINTER-BUDS.--Broadly ovoid, obtuse, light brown, 1/8-1/4 inch long.

BARK.--Twigs smooth, gray-green, becoming orange-brown, finally dark
gray-brown; thin, light gray-brown on the trunk, separating into thin,
plate-like scales.

WOOD.--Light, soft, weak, straight-grained, light yellow, with sapwood of
the same color.

DISTRIBUTION.--Common in the northern half of the Lower Peninsula and
throughout the Upper Peninsula.

HABITAT.--Low, damp woods; banks of streams; borders of lakes; high rocky
or sandy slopes; loves the cold winters.

NOTES.--A vigorous and beautiful tree in regions sufficiently cold.


[Illustration: +Black Spruce+

   1. Winter branchlet, × 1.
   2. Leaves, × 2.
   3. Cross-sections of leaves, enlarged.
   4-5. Opened cones, × 1.
   6. Cone-scale with seeds, × 1.]


+PINACEAE+

+Black Spruce+

_Picea mariana (Mill.) BSP._ [_Picea nigra Link_]


HABIT.--A small tree 20-30 feet high, with a trunk diameter of 6-10
inches; forming a narrow-based, conical, more or less irregular crown of
short, slender, horizontal branches; often small and stunted.

LEAVES.--Spirally arranged, spreading in all directions; awl-shaped,
4-sided, blunt at the apex, more or less incurved; stiff; dark
blue-green and glaucous; 1/8-3/8 inch long. Persistent for several
years.

FLOWERS.--April-May; monoecious; the staminate subglobose, about 1/2 inch
long, composed of many spirally arranged, dark red anthers; the
pistillate oblong-cylindrical, composed of broad, purple scales
(subtended by rounded, toothed, purple bracts) spirally arranged upon a
central axis, about 1/2 inch long.

FRUIT.--Autumn of first season, but persistent on the branch for many
years; pendent, ovoid, short-stalked cones, about 1 inch long; seeds
about 1/8 inch long, with pale brown wings 1/2 inch long.

WINTER-BUDS.--Ovoid, acute, light red-brown, puberulous, 1/8 inch long.

BARK.--Twigs at first green and rusty-pubescent, becoming dull red-brown
and rusty-pubescent; thin, gray-brown on the trunk, separating into
thin, appressed scales.

WOOD.--Light, soft, weak, pale yellow-white, with thin, pure white
sapwood.

DISTRIBUTION.--Occurs sparingly in southern Michigan; more abundant in
the northern portions.

HABITAT.--Cold, sphagnous bogs and swamps; shores of lakes.

NOTES.--Short-lived. Undesirable for ornamental planting. Growing to its
largest size in the far north.


[Illustration: +Norway Spruce+

   1. Branchlet with partly opened cone, × 1/2.
   2. Leaf, × 3.
   3. Cross-sections of leaves, enlarged.
   4. Cone-scale with seeds, × 1.]


+PINACEAE+

+Norway Spruce+

_Picea abies (L.) Karst._ [_Picea excelsa Link_]


HABIT.--A tree 50-70 feet high, with a trunk diameter of 1-3 feet;
forming a dense, conical, spire-topped crown of numerous, drooping
branches which persist nearly to the ground.

LEAVES.--Spirally arranged along the twig; crowded; 3/4-1 inch long;
rigid, curved, acute; lustrous, dark green. Persistent 5-7 years.

FLOWERS.--May; monoecious; the staminate ovoid to subglobose,
long-stalked, reddish to yellowish, 3/4-1 inch long; the pistillate
cylindrical, sessile, erect, 1-1/2-2 inches long.

FRUIT.--Autumn of first season; sessile, cylindrical cones 3-6 inches
long, pendent from the tips of the uppermost branches; sterile scales
very short, toothed; seeds red-brown, rough, 1/8 inch long, with long
wings.

WINTER-BUDS.--Ovoid, acute, red-brown, not resinous, about 3/8 inch long.

BARK.--Twigs red- or orange-brown, smooth or corrugated; becoming thin and
gray-brown on old trunks, slightly fissured, scaly.

WOOD.--Light, strong, tough, elastic, soft, fine-grained, white, with
thick, indistinguishable sapwood.

NOTES.--Grows to a height of 120-150 feet in northern Europe and Asia.
Perfectly hardy in Michigan. Easily transplanted. Adapts itself to a
variety of soils and climates. Grows rapidly, but is short-lived in our
country. Desirable for ornamental planting. Useful for shelter belts.


[Illustration: +Balsam Fir+

   1. Winter branchlet, × 1.
   2-3. Leaves, × 2.
   4. Cross-section of leaf, enlarged.
   5. Unopened cone, × 1.
   6. Cone-scale with seeds, × 1.]


+PINACEAE+

+Balsam Fir+

_Abies balsamea (L.) Mill._


HABIT.--A slender tree 40-60 feet high, with a trunk diameter of 12-18
inches; branches in whorls of 4-6, forming a symmetrical, open crown
widest at the base and tapering regularly upward.

LEAVES.--Scattered, spirally arranged in rows, on young trees extending
from all sides of the branch, on old trees covering the upper side of
the branch; narrowly linear, with apex acute or rounded; 1/2-1-1/4
inches long; lustrous, dark green above, pale beneath; sessile;
aromatic. Persistent 8-10 years.

FLOWERS.--May; monoecious; the staminate oblong-cylindrical, yellow, 1/4
inch long, composed of yellow anthers (subtended by scales) spirally
arranged upon a central axis; the pistillate oblong-cylindrical, 1 inch
long, composed of orbicular, purple scales (subtended by yellow-green
bracts) spirally arranged upon a central axis.

FRUIT.--Autumn of first season; oblong-cylindrical, erect, puberulous,
dark purple cones, 2-4 inches long, about 1 inch thick; seeds 1/4 inch
long, shorter than their light brown wings.

WINTER-BUDS.--Globose, orange-green, resinous, 1/8-1/4 inch in diameter.

BARK.--Twigs at first grayish and pubescent, becoming gray-brown and
smooth; thin and smooth on young trunks, pale gray-brown and marked by
swollen resin chambers; red-brown on old trunks and somewhat roughened
by small, scaly plates.

WOOD.--Very light, soft, weak, coarse-grained, perishable, pale brown,
with thick, lighter colored sapwood.

DISTRIBUTION.--Occasional in the southern half of the Lower Peninsula,
frequent in the northern half; abundant in the Upper Peninsula.

HABITAT.--Prefers cool, moist, rich soil; low, swampy ground;
well-drained hillsides.

NOTES.--Grows rapidly. Short-lived. Easily transplanted.


[Illustration: +Hemlock+

   1. Fruiting branch viewed from beneath, × 1/2.
   2. Leaf, × 3.
   3. Cross-section of leaf, enlarged.
   4. Branchlet with partly opened cone, × 1.
   5. Cone-scale with seeds, × 3.]


+PINACEAE+

+Hemlock+

_Tsuga canadensis (L.) Carr._


HABIT.--A large tree 60-80 feet high, with a trunk 2-4 feet in diameter;
forming a rather broad, open, somewhat irregular-pyramidal crown of
slender, horizontal branches.

LEAVES.--Spirally arranged around the branch, but appearing 2-ranked by
the twisting of their petioles; linear, flat, rounded at the apex; about
1/2 inch long; dark yellow-green and shining above, hoary beneath;
short-petioled. Persistent about 3 years.

FLOWERS.--April-May; monoecious; the staminate axillary, short-stalked,
light yellow, about 3/8 inch long, composed of subglobose clusters of
stamens; the pistillate terminal, oblong, pale green, 1/8 inch long, the
scales short, pinkish.

FRUIT.--Autumn of first season, gradually losing their seeds during the
winter and falling the next spring; oblong-ovoid, acute, short-stalked,
red-brown cones, about 3/4 inch long; seeds 1/8 inch long, with wings
about twice as long.

WINTER-BUDS.--Ovoid, obtuse, red-brown, slightly puberulous, 1/16 inch
long.

BARK.--Twigs at first pale brown and pubescent, becoming glabrous,
gray-brown; thick, red-brown or gray on the trunk, deeply divided into
narrow, rounded, scaly ridges.

WOOD.--Light, soft, weak, brittle, coarse- and crooked-grained, not
durable, ill-smelling, light red-brown, with thin, darker colored
sapwood.

DISTRIBUTION.--Throughout the state, with the exception of the
south-eastern portion; scarce on the east side of the state, more common
on the west, becoming very abundant in Emmet County.

HABITAT.--Prefers well-drained uplands and slopes of ravines.

NOTES.--A favorite hedge plant. Useful for ornamental planting in shady
situations.


[Illustration: +Arborvitae. White Cedar+

   1. Fruiting branchlet, × 1.
   2. Tip of branchlet, enlarged.
   3. Cone-scale with seeds, × 3.]


+PINACEAE+

+Arborvitae. White Cedar+

_Thuja occidentalis L._


HABIT.--A tree 40-50 feet high, with a short, often buttressed trunk 1-2
feet in diameter, often divided into 2-3 secondary stems; forming a
rather dense, wide-based, pyramidal crown.

LEAVES.--Opposite, 4-ranked, scale-like, appressed; ovate, obtuse or
pointed, keeled in the side pairs, flat in the others; 1/8-1/4 inch
long; yellow-green, often becoming brown in winter; strongly aromatic
when crushed. Persistent 1-2 years.

FLOWERS.--April-May; usually monoecious; the staminate minute, globose,
yellow, composed of 4-6 stamens arranged oppositely on a short axis; the
pistillate small, oblong, reddish, composed of 8-12 scales arranged
oppositely on a short axis.

FRUIT.--Early autumn of first season, but persistent on the branch
through the winter; erect, short-stalked, oblong-ovoid, pale brown
cones, about 1/2 inch long, composed of 8-12 loose scales; seeds 1/8
inch long, ovate, acute, winged.

WINTER-BUDS.--Naked, minute.

BARK.--Twigs yellow-green, becoming light red, finally smooth, lustrous,
dark orange-brown; thin, light red-brown on the trunk, slightly furrowed
or deciduous in ragged strips.

WOOD.--Light, soft, brittle, rather coarse-grained, durable, fragrant,
pale yellow-brown, with thin, whitish sapwood.

DISTRIBUTION.--Throughout the Upper Peninsula, Lower Peninsula as far
south as Montcalm County.

HABITAT.--Prefers moist soil in low swamps and along river-banks.

NOTES.--Slow of growth. Tolerant of all soils and exposures. Especially
useful for hedges or narrow evergreen screens.


[Illustration: +Red Juniper. Red Cedar+

   1. Branchlet with awl-shaped leaves, × 1.
   2. Tip of branchlet, showing awl-shaped leaves, enlarged.
   3. Fruiting branchlet with scale-like leaves, × 1.
   4. Tip of branchlet, showing scale-like leaves, enlarged.]


+PINACEAE+

+Red Juniper. Red Cedar+

_Juniperus virginiana L._


HABIT.--A medium-sized tree 30-40 feet high, with a trunk diameter of 1-2
feet; forming an irregular, pyramidal or rounded crown.

LEAVES.--Opposite, of two kinds: (1) sessile, scale-like, closely
appressed, overlapping, 4-ranked, ovate, acute, 1/16 inch long, (2)
sessile, awl-shaped, loosely arranged, 1/4-1/2 inch long. Persistent 5-6
years.

FLOWERS.--May; usually dioecious; minute; the staminate oblong-ovoid,
composed of 4-6 shield-like scales, each bearing 4-5 yellow, globose
pollen sacs; the pistillate ovoid, composed of about 3 pairs of flesh,
bluish scales, united at the base and bearing 2 ovules.

FRUIT.--Autumn of first or second season; subglobose, berry-like
strobile, about 1/4 inch in diameter, dark blue and glaucous; flesh
sweet and resinous; seeds 2-3.

WINTER-BUDS.--Naked, minute.

BARK.--Twigs greenish to red-brown and smooth; thin, light red-brown on
the trunk, exfoliating lengthwise into long, narrow, persistent strips,
exposing the smooth, brown inner bark.

WOOD.--Light, soft, close-grained, brittle, weak, durable, very fragrant,
dull red, with thin, whitish sapwood.

DISTRIBUTION.--Occurs sparingly throughout the state; most abundant in
the southern portion.

HABITAT.--Prefers loamy soil on sunny slopes; dry, rocky hills; also
borders of lakes and streams, peaty swamps.

NOTES.--Slow of growth. Long-lived. Should be transplanted with ball of
earth. Tolerant of varied soils and situations.


+SUMMER KEY TO THE SPECIES OF SALIX+[D]

   a. Leaf-petioles without glands.

   b. Leaves 1/4-3/4 inch broad; petioles broad and flat. _S.
   nigra_, p. 37.

   bb. Leaves 3/4-1/4 inches broad; petioles slender and terete.
   _S. amygdaloides_, p. 39.

   aa. Leaf-petioles glandular above.

   b. Leaves 1/4-1/2 inch broad, sharp-serrate; tree with weeping
   habit. _S. babylonica_, p. 43.

   bb. Leaves 1/2-1-1/2 inches broad, blunt-serrate; tree with
   upright habit. _S. fragilis_, p. 41.


+WINTER KEY TO THE SPECIES OF SALIX+

The classification of the Willows is a task for the specialist, even
when leaves and both staminate and pistillate flowers are obtainable. It
is impractible for the novice to attempt the determination of species of
Salix with winter characters alone. Consequently the usual winter key is
omitted.


+SALICACEAE+

+Willow+

_Salix (Tourn.) L._


The genus _Salix_ is represented in Michigan by thirty or more distinct
species, and there are many more hybrids. The majority of these are
shrubs, only a few becoming truly arborescent. Because of the similarity
of their botanical characters, the frequency with which they hybridize,
and the facility with which they respond to their environment only an
expert is competent to identify the species so abundant along our water
courses and on the banks of our lakes and swamps. The scope of this work
being necessarily limited, it has been deemed best to describe but two
of our native willows and two of our foreign neighbors which are
frequently planted.


[Illustration: +Black Willow+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1.
   4. Staminate flowering branchlet, × 1.
   5. Staminate flower, enlarged.
   6. Pistillate flowering branchlet, × 1.
   7. Pistillate flower, enlarged.
   8. Fruiting branchlet, × 1.]


+SALICACEAE+

+Black Willow+

_Salix nigra Marsh._


HABIT.--A tree 30-50 feet high, with a short trunk, 1-2 feet in diameter;
stout, spreading branches form a broad, rather irregular, open crown.
Often a shrub.

LEAVES.--Alternate, simple, 3-6 inches long, 1/4-3/4 inch broad;
lanceolate, very long-pointed, often curved at the tip; finely serrate;
thin; bright green and rather lustrous above, paler and often hairy
beneath; petioles very short, more or less pubescent.

FLOWERS.--April-May, with the leaves; dioecious; borne in crowded,
slender, hairy catkins, 1-3 inches long; calyx 0; corolla 0; scales
yellow, villous, stamens 3-6; ovary ovoid-conical, short-stalked, with
stigmas nearly sessile.

FRUIT.--June; ovoid-conical capsule, 1/8 inch long, containing many
minute seeds which are furnished with long, silky, white hairs.

WINTER-BUDS.--Terminal bud absent; lateral buds narrow-conical, acute,
lustrous, red-brown, 1/8 inch long.

BARK.--Twigs glabrous or pubescent, bright red-brown, becoming darker
with age; thick, dark brown or nearly black on old trunks, deeply
divided into broad, flat ridges, often becoming shaggy.

WOOD.--Light, soft, weak, close-grained, light red-brown, with thin,
whitish sapwood.

DISTRIBUTION.--Common throughout the state.

HABITAT.--Banks of streams and lake-shores.

NOTES.--Branchlets very brittle at the base, and these, broken off by the
wind, are carried down stream, often catching in the muddy banks and
there taking root.


[Illustration: +Almondleaf Willow+

   1. Winter twig, × 1.
   2. Lateral bud, enlarged.
   3. Leaf, × 1.
   4. Staminate flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flowering branchlet, × 1/2.
   7. Pistillate flower, enlarged.
   8. Fruiting branchlet, × 1/2.]


+SALICACEAE+

+Almondleaf Willow+

_Salix amygdaloides Anders._


HABIT.--A tree 30-40 feet high, with a straight, columnar trunk 1-2 feet
in diameter; straight, ascending branches form a rather narrow, rounded
crown.

LEAVES.--Alternate, simple, 2-6 inches long, 3/4-1-1/4 inches broad;
lanceolate to ovate-lanceolate, long-pointed; finely serrate; thin and
firm; light green and shining above, pale and glaucous beneath; petioles
slender, 1/2-3/4 inch long.

FLOWERS.--April, with the leaves; dioecious; borne in crowded, slender,
pubescent catkins 2-3 inches long; calyx 0; corolla 0; scales yellow,
villous both sides; stamens 5-9; ovary oblong-conical, with stigmas
nearly sessile.

FRUIT.--May; 1-celled, globose-conical capsule, 1/4 inch long, containing
many minute seeds which are furnished with long, silky, white hairs.

WINTER-BUDS.--Terminal bud absent; lateral buds broadly ovoid, gibbous,
lustrous, dark brown, 1/8 inch long.

BARK.--Twigs glabrous, lustrous, dark orange or red-brown becoming darker
orange-brown; thick and brown on old trunks, irregularly fissured into
flat, connected ridges.

WOOD.--Light, soft, weak, close-grained, light brown, with thick, whitish
sapwood.

DISTRIBUTION.--Common throughout the state.

HABITAT.--Banks of streams.

NOTES.--Hybridizes freely with other willows, making its identification
difficult.


[Illustration: +Crack Willow. Brittle Willow+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1.
   4. Staminate flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flowering branchlet, × 1/2.
   7. Pistillate flower, enlarged.
   8. Fruiting branchlet, × 1/2.]


+SALICACEAE+

+Crack Willow. Brittle Willow+

_Salix fragilis L._


HABIT.--A tree 50-60 feet high, with a short, stout trunk 3-4 feet in
diameter; stout, spreading branches form a broad, open crown.

LEAVES.--Alternate, simple, 3-6 inches long, 1/2-1-1/2 inches broad;
lanceolate, long-pointed; finely glandular-serrate; thin and firm;
lustrous, dark green above, paler beneath, glabrous both sides; petioles
short, stout, with 2 glands at the junction of blade and petiole.

FLOWERS.--April-May, with the leaves; dioecious; borne in slender,
pubescent catkins 1-3 inches long; calyx 0; corolla 0; scales blunt,
somewhat pubescent; stamens usually 2; ovary abortive, with stigmas
nearly sessile. Staminate trees rare.

FRUIT.--April-May; 1-celled, long-conical, short-stalked capsule, about
1/4 inch long, containing many minute seeds which are furnished with
long, silky, white hairs.

WINTER-BUDS.--Terminal bud absent; lateral buds long-conical, pointed,
glabrous, bright red-brown, about 1/4 inch long.

BARK.--Twigs pubescent, yellow-green, often reddish, becoming glabrous,
lustrous, brown; thick, gray on the trunk, smooth in young trees, very
rough, irregularly scaly-ridged in old trees.

WOOD.--Light, soft, tough, close-grained, red-brown, with thick, whitish
sapwood.

NOTES.--A native of Europe and Asia, where it is a valuable timber tree.
Hardy throughout the state and of very rapid growth. Thrives in rich,
damp soil. Easily grown from cuttings. The twigs are very brittle at the
base and are easily broken by the wind, hence the name Brittle Willow.


[Illustration: +Weeping Willow. Napoleon's Willow+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1.
   4. Pistillate flowering branchlet, × 1/2.
   5. Pistillate flower, enlarged.
   6. Fruiting branchlet, × 1/2.]


+SALICACEAE+

+Weeping Willow. Napoleon's Willow+

_Salix babylonica L._


HABIT.--A tree 40-50 feet high, with a short, stout trunk 3-4 feet in
diameter; the long, slender branchlets, often many feet in length, droop
in graceful festoons, giving to the tree a weeping habit.

LEAVES.--Alternate, simple, 3-7 inches long, 1/4-1/2 inch broad; linear
to linear-lanceolate, long-pointed; finely sharp-serrate; thin and firm;
glabrous, dark green above, paler beneath; petioles 1/2 inch or less in
length, glandular above, often hairy.

FLOWERS.--April-May, with the leaves; dioecious; borne in slender, nearly
glabrous catkins 1-2 inches long; calyx 0; corolla 0; scales
ovate-lanceolate, slightly hairy; ovary ovoid-conical, very
short-stalked, with stigmas longer than the style. Staminate trees
apparently do not occur in the United States.

FRUIT.--May-June; 1-celled, narrow-ovoid, sessile capsule, about 3/16
inch long, containing many minute seeds which are furnished with long,
silky, white hairs.

WINTER-BUDS.--Terminal bud absent; lateral buds narrow-conical,
sharp-pointed, somewhat flattened, brownish, 1/8-1/4 inch long.

BARK.--Twigs glabrous, olive-green; thick and gray on old trunks, rather
smooth, or irregularly fissured into shallow, firm ridges.

WOOD.--Light, soft, weak, close-grained, light brown, with thick, whitish
sapwood.

NOTES.--A native of Europe and Asia. Often grown in cemeteries. Easily
propagated by cuttings. Rapid of growth in rich, damp soil. Sometimes
winter-killed because the wood is not ripened.


SUMMER KEY TO THE SPECIES OF POPULUS

   a. Leaf-petioles essentially terete.

   b. Petioles and lower sides of leaves pubescent; leaves
   heart-shaped. _P. candicans_, p. 55.

   bb. Petioles and lower sides of leaves glabrous; leaves
   ovate-lanceolate. _P. balsamifera_, p. 53.

   aa. Leaf-petioles strongly flattened.

   b. Petioles and lower sides of leaves tomentose; twigs
   pubescent. _P. alba_, p. 47.

   bb. Petioles and lower sides of leaves glabrous; twigs
   glabrous.

   c. Leaves distinctly deltoid in shape.

   d. Leaves broader than they are long, abruptly acuminate at
   the apex; marginal teeth not conspicuously incurved; branches
   erect and more or less appressed to the main stem, forming a
   narrow, spire-like crown. _P. nigra italica_, p. 59.

   dd. Leaves longer than they are broad, more or less
   taper-pointed at the apex; marginal teeth rather conspicuously
   incurved; branches spreading, forming a broad crown. _P.
   deltoides_, p. 57.

   cc. Leaves ovate to nearly orbicular in shape.

   d. Margin of leaves coarsely sinuate-toothed; leaves 3-5
   inches long. _P. grandidentata_, p. 51.

   dd. Margin of leaves finely serrate; leaves less than 3 inches
   long. _P. tremuloides_, p. 49.


+WINTER KEY TO THE SPECIES OF POPULUS+

   a. Branches erect, more or less appressed to the main stem,
   forming a narrow, spire-like crown. _P. nigra italica_, p. 59.

   aa. Branches spreading, forming a broad crown.

   b. Terminal buds 1/8-1/4 inch long, not resinous.

   c. Buds and twigs more or less conspicuously white-downy;
   twigs green. _P. alba_, p. 47.

   cc. Buds and twigs not conspicuously white-downy; twigs
   usually red-brown.

   d. Terminal buds about 1/8 inch long, puberulous,
   dusty-looking; lateral buds widely divergent; twigs rather
   coarse. _P. grandidentata_, p. 51.

   dd. Terminal buds about 1/4 inch long, glabrous, lustrous;
   lateral buds more or less appressed; twigs rather slender. _P.
   tremuloides_, p. 49.

   bb. Terminal buds 1/2-1 inch long, sticky-resinous.

   c. Terminal buds about 1/2 inch long; buds not fragrant; twigs
   usually yellow, more or less strongly angled. _P. deltoides_,
   p. 57.

   cc. Terminal buds nearly 1 inch long; buds fragrant; twigs
   usually red-brown and seldom strongly angled. _P.
   balsamifera_[E] p. 53. _P. candicans_[E] p. 55.


[Illustration: +White Poplar+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 2.
   4. Staminate flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flowering branchlet, × 1/2.
   7. Pistillate flower, enlarged.
   8. Fruit, × 1/2.]


+SALICACEAE+

+White Poplar+

_Populus alba L._


HABIT.--A large tree 60-80 feet high, with a trunk diameter of 2-4 feet,
forming a large, spreading, rounded or irregular crown of large, crooked
branches and sparse, stout branchlets.

LEAVES.--Alternate, simple, 2-4 inches long and almost as broad; broadly
ovate to suborbicular; irregularly toothed, sinuate, or sometimes
3-5-lobed; glabrous, dark green above, white-tomentose to glabrous
beneath; petioles long, slender, flattened, tomentose.

FLOWERS.--April-May, before the leaves; dioecious; the staminate catkins
thick, cylindrical, 2-4 inches long; the pistillate catkins slender, 1-2
inches long; calyx 0; corolla 0; stamens 6-16, with purple anthers;
stigmas 2, branched, yellow.

FRUIT.--May-June; ovoid, 2-valved capsules, 1/8-1/4 inch long, borne in
drooping catkins 2-4 inches long; seeds light brown, surrounded by long,
white hairs.

WINTER-BUDS.--Ovoid, pointed, not viscid, downy, about 1/4 inch long.

BARK.--Twigs greenish, covered with a white down, becoming greenish gray
and marked with darker blotches; dark gray and fissured at the base of
old trunks.

WOOD.--Light, soft, weak, difficult to split, reddish yellow, with thick,
whitish sapwood.

NOTES.--A native of Europe and Asia. Hardy in Michigan. Grows rapidly in
good soils; thrives in poor soils and exposed situations. Roots deep,
producing numerous suckers for a considerable distance from the tree.


[Illustration: +Aspen+

   1. Winter twig, × 2.
   2. Leaf, × 1.
   3. Staminate flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flowering branchlet, × 1/2.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1/2.]


+SALICACEAE+

+Aspen+

_Populus tremuloides Michx._


HABIT.--A small, slender tree generally 35-45 feet high, with a trunk
diameter of 8-15 inches; forming a loose, rounded crown of slender
branches.

LEAVES.--Alternate, simple, 1-1/2-2-1/2 inches long and broad; broadly
ovate to suborbicular; finely serrate; thin and firm; lustrous, dark
green above, dull and pale beneath; petioles slender, laterally
compressed. Tremulous with the slightest breeze.

FLOWERS.--April, before the leaves; dioecious; the staminate catkins
1-1/2-3 inches long, the pistillate at first about the same length,
gradually elongating; calyx 0; corolla 0; stamens 6-12; stigmas 2,
2-lobed, red.

FRUIT.--May-June; 2-valved, oblong-cylindrical, short-pedicelled capsules
1/4 inch long; seeds light brown, white-hairy.

WINTER-BUDS.--Terminal bud about 1/4 inch long, narrow-conical, acute,
red-brown, lustrous; lateral buds often appressed.

BARK.--Twigs very lustrous, red-brown, becoming grayish and roughened by
the elevated leaf-scars; thin, yellowish or greenish and smooth on the
trunk, often roughened with darker, horizontal bands or wart-like
excrescences, becoming thick and fissured, almost black at the base of
old trunks.

WOOD.--Light, soft, weak, close-grained, not durable, light brown, with
thin, whitish sapwood.

DISTRIBUTION.--Common throughout the state, but most abundant in the
Upper Peninsula.

HABITAT.--Prefers moist, sandy soil and gravelly hillsides.

NOTES.--One of the first trees to cover burned-over lands. Grows rapidly.
Usually short-lived. Propagated from seed or cuttings.


[Illustration: +Largetooth Aspen+

   1. Winter twig, × 2.
   2. Leaf, × 1.
   3. Staminate flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flowering branchlet, × 1/2.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1/2.]


+SALICACEAE+

+Largetooth Aspen+

_Populus grandidentata Michx._


HABIT.--A medium-sized tree 30-50 feet high, with a slender trunk 12-20
inches in diameter; forming a loose, oval or rounded crown of slender,
spreading branches and coarse spray.

LEAVES.--Alternate, simple, 3-5 inches long, two-thirds as broad;
orbicular-ovate; coarsely and irregularly sinuate-toothed; thin and
firm; dark green above, paler beneath, glabrous both sides; petioles
long, slender, laterally compressed.

FLOWERS.--April, before the leaves; dioecious; the staminate in
short-stalked catkins 1-3 inches long; the pistillate in loose-flowered,
long-stalked catkins at first about the same length, but gradually
elongating; calyx 0; corolla 0; stamens 6-12, with red anthers; stigmas
2, 2-lobed, red.

FRUIT.--May; 2-valved, conical, acute, hairy capsules 1/8 inch long,
borne in drooping catkins 4-6 inches long; seeds minute, dark brown,
hairy.

WINTER-BUDS.--Terminal bud 1/8 inch long, ovoid to conical, acute, light
chestnut, puberulous, dusty-looking.

BARK.--Twigs greenish gray and at first hoary-tomentose, becoming
lustrous, orange or red-brown and finally greenish gray; thick, dark
red-brown or blackish at the base of old trunks, irregularly fissured,
with broad, flat ridges.

WOOD.--Light, soft, weak, close-grained, light brown, with thin, whitish
sapwood.

DISTRIBUTION.--A common tree in the northern portions of the Lower
Peninsula, but rare in the Upper Peninsula.

HABITAT.--Prefers rich, moist, sandy soil; borders of swamps;
river-banks; hillsides.

NOTES.--Grows rapidly in many soils. Easily transplanted. Short-lived.
Useful for temporary effect. Propagated from seed or cuttings.


[Illustration: +Balm of Gilead. Balsam+

   1. Winter twig, × 1.
   2. Leaf, × 3/4.
   3. Staminate flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Catkin of pistillate flower, × 1/2.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1/2.]


+SALICACEAE+

+Balm of Gilead. Balsam+

_Populus balsamifera L._


HABIT.--A tree 60-75 feet high, with a trunk diameter of 1-3 feet;
forming a rather narrow, open, pyramidal crown of few, slender,
horizontal branches.

LEAVES.--Alternate, simple, 3-6 inches long, about one-half as broad;
ovate to ovate-lanceolate; finely crenate-serrate; thin and firm;
lustrous, dark green above, paler beneath; petioles 1-1/2 inches long,
slender, terete, smooth.

FLOWERS.--April, before the leaves; dioecious; the staminate in
long-stalked catkins 3-4 inches long; the pistillate in loose-flowered,
long-stalked catkins 4-5 inches long; calyx 0; corolla 0; stamens 20-30,
with bright red anthers; ovary short-stalked; stigmas 2, wavy-margined.

FRUIT.--May-June; 2-valved, ovoid, short-pedicelled capsules 1/4 inch
long, borne in drooping catkins 4-6 inches long; seeds light brown,
hairy.

WINTER-BUDS.--Terminal bud about 1 inch long, ovoid, long-pointed,
brownish, resin-coated, sticky, fragrant.

BARK.--Twigs red-brown, becoming dark orange, finally green-gray; thick,
grayish on old trunks, and shallowly fissured into broad, rounded
ridges, often roughened by dark excrescences.

WOOD.--Light, soft, weak, close-grained, light red-brown, with thick,
nearly white sapwood.

DISTRIBUTION.--Occurs throughout the entire state, but is more abundant
and of greater size in the northern portions.

HABITAT.--Prefers river bottom-lands and borders of swamps.

NOTES.--Rapid in growth. Spreads from the roots. Most useful for
shelter belts. Easily transplanted. Propagated from cuttings.


[Illustration: +Hairy Balm of Gilead. Balsam+

   1. Winter twig, × 1.
   2. Leaf, × 1/2.
   3. Staminate flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flowering branchlet, × 1/2.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1/2.]


+SALICACEAE+

+Hairy Balm of Gilead. Balsam+

_Populus candicans Ait._ [_Populus balsamifera candicans (Ait.) Gray_]


HABIT.--A tree 50-70 feet high, with a trunk diameter of 1-3 feet; more
spreading branches than in _P. balsamifera_, forming a broader and more
open crown.

LEAVES.--Resemble those of _P. balsamifera_, but more broadly
heart-shaped and more coarsely serrate; more or less pubescent when
young; petioles pubescent.

FLOWERS.--Similar to those of _P. balsamifera_.

FRUIT.--Similar to that of _P. balsamifera_.

WINTER-BUDS.--Terminal bud about 1 inch long, ovoid, long-pointed, dark
red-brown, resinous throughout, viscid, very aromatic.

BARK.--Twigs reddish or olive-green, with occasional longitudinal gray
lines, covered with a fragrant, gummy secretion, becoming gray-green;
dark gray, rough, irregularly striate and firm on old trunks.

WOOD.--Resembles that of _P. balsamifera_, but is somewhat heavier.

DISTRIBUTION.--Indigenous to the northern portions of the state, but
often cultivated and occasionally escaping in the southern portion.

HABITAT.--In a great variety of soils and situations.

NOTES.--Grows rapidly in all soils and situations. Suckers readily from
the roots. Propagated from cuttings.


[Illustration: +Cottonwood+

   1. Winter twig, × 1.
   2. Leaf, × 1/2.
   3. Staminate flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate catkin, × 1/2.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1/2.]


+SALICACEAE+

+Cottonwood+

_Populus deltoides Marsh._ [_Populus monilifera Ait._]


HABIT.--A stately tree attaining a height of 70-90 feet and a trunk
diameter of 3-5 feet; forming a spreading, open, symmetrical crown of
massive, horizontal branches and stout, more or less angled branchlets.

LEAVES.--Alternate, simple, 3-6 inches long, nearly as broad; broadly
deltoid-ovate; coarsely crenate-serrate above the entire base; thick and
firm; lustrous, dark green above, paler beneath; petioles 2-3 inches
long, slender, compressed laterally.

FLOWERS.--April-May, before the leaves; dioecious; the staminate in
short-stalked, densely-flowered catkins 3-4 inches long; the pistillate
in short-stalked, few-flowered catkins elongating to 6-8 inches; calyx
0; corolla 0; stamens very numerous, with red anthers; stigmas 3-4,
spreading.

FRUIT.--May; 2-4-valved, short-stalked capsules, borne in drooping
catkins 5-10 inches long; seeds light brown, densely cottony.

WINTER-BUDS.--Terminal bud 1/2 inch long, conical, acute, very resinous,
shining, brownish.

BARK.--Twigs and young stems smooth, yellow-green; old trunks ashy gray,
deeply divided into straight furrows with broad, rounded ridges.

WOOD.--Light, soft, weak, close-grained, dark brown, with thick, whitish
sapwood; warps badly and is difficult to season.

DISTRIBUTION.--Entire Michigan; rare in the northern portions.

HABITAT.--Prefers rich, moist soil; river-banks; river-bottoms;
lake-shores; grows well in drier situations.

NOTES.--Rapid of growth, consequently an excellent tree for immediate
effect. Propagated from cuttings.


[Illustration: +Lombardy Poplar+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 3/4.
   4. Staminate flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.]


+SALICACEAE+

+Lombardy Poplar+

_Populus nigra italica DuRoi_ [_Populus fastigiata Desf._] [_Populus
dilatata Ait._]


HABIT.--A tree 75-100 feet high, with a short, ridged and buttressed
trunk 4-6 feet in diameter and a narrow, spire-like crown of erect
branches.

LEAVES.--Alternate, simple, 2-4 inches long, and usually somewhat broader
than long; broad-deltoid, abruptly acuminate; finely but bluntly
crenate-serrate; thick and firm; dark green and shining above, lighter
and more or less lustrous beneath; petioles slender, laterally
compressed, 1-2 inches long.

FLOWERS.--April-May, before the leaves; dioecious; the staminate in
sessile, dark red, cylindrical catkins about 3 inches long; the
pistillate not present in the United States; calyx 0; corolla 0; stamens
about 8, with white filaments and purple anthers.

FRUIT.--Not formed in the United States in the absence of pistillate
flowers.

WINTER-BUDS.--Terminal bud conical, slightly angled, taper-pointed,
glutinous, about 3/8 inch long; lateral buds smaller, appressed.

BARK.--Twigs glabrous, shining yellow, becoming gray; thick and
gray-brown on old trunks, deeply and irregularly furrowed.

WOOD.--Light, soft, easily worked, not liable to splinter, weak, not
durable, light red-brown, with thick, nearly white sapwood.

NOTES.--Thought to be a native of Afghanistan. Very rapid in growth.
Short-lived. Spreads by means of suckers and fallen branches. Useful for
ornamental purposes. Because of crowding the limbs die early, which
remain and cause the tree to look unsightly.


+SUMMER KEY TO THE SPECIES OF JUGLANS+

   a. Leaflets 11-17, the terminal usually present; pith of twigs
   chocolate-brown; bark of trunk rather smooth, or fissured,
   with broad, flat, whitish ridges; fruit elongated,
   sticky-downy. _J. cinerea_, p. 63.

   aa. Leaflets 13-23, the terminal often lacking; pith of twigs
   cream colored; bark of trunk rough, brownish or blackish,
   deeply furrowed by broad, rounded ridges; fruit globose, not
   sticky-downy. _J. nigra_, p. 65.


+WINTER KEY TO THE SPECIES OF JUGLANS+

   a. Pith chocolate-brown; leaf-scar with downy pad above; fruit
   elongated, sticky-downy; terminal bud 1/2-3/4 inch long; bark
   rather smooth, or fissured, with broad, flat, whitish ridges.
   _J. cinerea_, p. 63.

   aa. Pith cream colored; leaf-scar without downy pad above;
   fruit globose, not sticky-downy; terminal bud 1/3 inch long;
   bark rough, brownish or blackish, deeply furrowed by broad,
   rounded ridges. _J. nigra_, p. 65.


[Illustration: +Butternut+

   1. Winter twig, × 1.
   2. Leaf, × 1/6
   3. Leaflet, × 1/2
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1/2.]


+JUGLANDACEAE+

+Butternut+

_Juglans cinerea L._


HABIT.--A medium-sized tree 40-60 feet high, with a short trunk 2-3 feet
in diameter; forming a wide-spreading crown of large, horizontal
branches and stout, stiff branchlets.

LEAVES.--Alternate, compound, 15-30 inches long. Leaflets 11-17, 2-4
inches long and one-half as broad; sessile, except the terminal;
oblong-lanceolate; finely serrate; thin; yellow-green and rugose above,
pale and soft-pubescent beneath. Petioles stout, hairy.

FLOWERS.--May, with the leaves; monoecious; the staminate in cylindrical,
greenish, drooping catkins 3-5 inches long; calyx 6-lobed, borne on a
hairy bract; corolla 0; stamens 8-12, with brown anthers; the pistillate
solitary or several on a common peduncle, about 1/3 inch long, their
bracts and bractlets sticky-hairy; calyx 4-lobed, hairy; corolla 0;
styles 2; stigmas 2, fringed, spreading, bright red.

FRUIT.--October; about 2-1/2 inches long, cylindrical, pointed, greenish,
sticky-downy, solitary or borne in drooping clusters of 3-5; nuts with
rough shells, inclosing a sweet, but oily kernel; edible.

WINTER-BUDS.--Terminal bud 1/2-3/4 inch long, oblong-conical, obliquely
blunt, somewhat flattened, brownish, pubescent.

BARK.--Twigs orange-brown or bright green, rusty-pubescent, becoming
smooth and light gray; gray and smoothish on young trunks, becoming
brown on old trunks, narrow-ridged, with wide furrows.

WOOD.--Light, soft, weak, coarse-grained, light brown, with thin, lighter
colored sapwood.

DISTRIBUTION.--Of common occurrence in the southern half of the Lower
Peninsula.

HABITAT.--Prefers low, rich woods; river-banks; low hillsides.

NOTES.--Leaves appear late and fall early. Pith chambered,
chocolate-brown. Large trees usually unsound. Not easily transplanted.


[Illustration: +Black Walnut+

   1. Winter twig, × 1.
   2. Leaf, × 1/6.
   3. Leaflet, × 1/2.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, back view, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1/2.]


+JUGLANDACEAE+

+Black Walnut+

_Juglans nigra L._


HABIT.--A large tree 60-80 feet high, with a massive trunk 2-5 feet in
diameter; forming an open, capacious crown of heavy branches and coarse
branchlets.

LEAVES.--Alternate, compound, 1-2 feet long. Leaflets 13-23, the terminal
often lacking, 2-4 inches long and one-half as broad; sessile;
ovate-lanceolate, taper-pointed; sharp-serrate; thin; yellow-green and
glabrous above, lighter and soft-pubescent beneath. Petioles stout,
pubescent. Foliage aromatic when bruised.

FLOWERS.--May, with the leaves; monoecious; the staminate in cylindrical,
greenish, drooping catkins 3-5 inches long; calyx 6-lobed, borne on a
hairy bract; corolla 0; stamens numerous, with purple anthers; the
pistillate solitary or several on a common peduncle, about 1/4 inch
long, their bracts and bractlets hairy; calyx 4-lobed, pubescent;
corolla 0; styles and stigmas 2.

FRUIT.--October; globose, 1-1/2-2 inches in diameter, smooth, not viscid;
solitary or borne in clusters of 2-3; nuts with irregularly furrowed
shell, inclosing a sweet, edible kernel.

WINTER-BUDS.--Terminal bud 1/3 inch long, ovoid, obliquely blunt,
slightly flattened, silky-tomentose.

BARK.--Twigs brownish and hairy, becoming darker and smooth; thick,
brownish or blackish on the trunk and deeply furrowed by broad, rounded
ridges.

WOOD.--Heavy, hard, strong, close-grained, very durable in contact with
the soil, rich dark brown, with thin, lighter colored sapwood.

DISTRIBUTION.--Lower Peninsula as far north as Bay City, but more
abundant in the southern portion of its range.

HABITAT.--Prefers rich bottom-lands and fertile hillsides.

NOTES.--Leaves appear late and fall early. Fruit very aromatic. Pith
chambered, cream colored. The juices from the husk stain the hands
brown. Not easily transplanted. Often infested with caterpillars.


+SUMMER KEY TO THE SPECIES OF CARYA+

   a. Bark of trunk essentially smooth, not deeply furrowed nor
   shaggy; husk of fruit less than 1/8 inch thick.

   b. Leaflets usually 5-7, glabrous beneath; buds dome-shaped,
   greenish; kernel of nut sweet.

   c. Twigs long-hairy; fruit less than 1 inch long. _C.
   microcarpa_, p. 75.

   cc. Twigs glabrous or nearly so; fruit 1-1/2-2 inches long.
   _C. glabra_, p. 77.

   bb. Leaflets usually 7-11, more or less downy beneath; buds
   elongated, bright yellow; kernel of nut bitter. _C.
   cordiformis_, p. 79.

   aa. Bark of trunk deeply furrowed or shaggy; husk of fruit
   more than 1/8 inch thick.

   b. Twigs more or less pubescent; leaflets 5-7, more or less
   pubescent beneath.

   c. Twigs brownish; buds densely hairy; fruit 1-1/2-2 inches
   long. _C. alba_, p. 73.

   cc. Twigs orange; buds merely puberulous; fruit 1-3/4-2-1/2
   inches long; (leaflets usually 7). _C. laciniosa_, p. 71.

   bb. Twigs tending to be glabrous; leaflets usually 5, glabrous
   beneath. _C. ovata_, p. 69.


+WINTER KEY TO THE SPECIES OF CARYA+

   a. Bark of trunk essentially smooth, not deeply furrowed nor
   shaggy; husk of fruit less than 1/8 inch thick.

   b. Terminal bud narrow, long-pointed, flattish, bright yellow;
   kernel of nut bitter. _C. cordiformis_, p. 79.

   bb. Terminal bud broad, dome-shaped, not bright yellow; kernel
   of nut sweet.

   c. Buds greenish; twigs glabrous; fruit 1-1/2-2 inches long.
   _C. glabra_, p. 77.

   cc. Buds red-brown; twigs long-hairy; fruit less than 1 inch
   long. _C. microcarpa_, p. 75.

   aa. Bark of trunk deeply furrowed or shaggy; husk of fruit
   more than 1/8 inch thick.

   b. Twigs more or less pubescent; buds more or less pubescent.

   c. Buds 1/2-3/4 inch long, densely hairy; outer bud-scales
   deciduous in autumn; twigs brownish; fruit 1-1/2-2 inches
   long. _C. alba_, p. 73.

   cc. Buds about 1 inch long, merely puberulous; outer
   bud-scales persistent until spring; twigs orange colored;
   fruit 1-3/4-2-1/2 inches long. _C. laciniosa_, p. 71.

   bb. Twigs tending to be glabrous; buds glabrous or nearly so.
   _C. ovata_, p. 69.


[Illustration: Shagbark Hickory. Shellbark Hickory

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/3.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1/2.]


+JUGLANDACEAE+

+Shagbark Hickory. Shellbark Hickory+

_Carya ovata (Mill.) K. Koch_ [_Hicoria ovata (Mill.) Britt._] [_Carya
alba Nutt_.]


HABIT.--A tree 60-80 feet high, with a slender, columnar trunk 1-2 feet
in diameter; forming a narrow, somewhat open crown of stout, slightly
spreading limbs and stout branchlets.

LEAVES.--Alternate, compound, 8-14 inches long. Leaflets usually 5, the
upper 5-7 inches long and 2-3 inches broad; sessile, except the
terminal; obovate to oblong-lanceolate; finely serrate; thick and firm;
glabrous, dark green above, paler beneath and glabrous or puberulous.
Petioles stout, smooth or hairy. Foliage fragrant when crushed.

FLOWERS.--May, after the leaves; monoecious; the staminate hairy,
greenish, in pendulous, ternate catkins 4-5 inches long, on a common
peduncle about 1 inch long; scales 3-parted, bristle-tipped; stamens 4,
with bearded, yellow anthers; the pistillate in 2-5-flowered spikes, 1/3
inch long, brown-tomentose; calyx 4-lobed, hairy; corolla 0; stigmas 2,
large, fringed.

FRUIT.--October; globular, 1-2 inches long, with thick husk separating
completely; nut usually 4-ridged, with thick shell and large, sweet,
edible kernel.

WINTER-BUDS.--Terminal bud 1/2-3/4 inch long, broadly ovoid, obtuse, dark
brown, pale-tomentose or nearly glabrous.

BARK.--Twigs brownish, more or less downy, becoming smooth and grayish;
thick and grayish on old trunks, separating into thick strips 1-3 feet
long, free at one or both ends, giving a characteristic shaggy
appearance.

WOOD.--Heavy, very hard and strong, tough, close-grained, elastic, light
brown, with thin, whitish sapwood.

DISTRIBUTION.--Common in the Lower Peninsula as far north as Roscommon
County.

HABITAT.--Prefers light, well-drained, loamy soil; low hillsides;
river-banks.

NOTES.--Hardy throughout its range. Moderately rapid in growth. Difficult
to transplant.


[Illustration: Shellbark Hickory. King Nut

   1. Winter twig, × 1/2.
   2. Leaf, × 1/4.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1/2.]


+JUGLANDACEAE+

+Shellbark Hickory. King Nut+

_Carya laciniosa (Michx. f.) Loud._ [_Hicoria laciniosa (Michx. f.)
Sarg._] [_Carya sulcata Nutt._]


HABIT.--A tree 60-80 feet high, with a tall, slender trunk 2-3 feet in
diameter; forming a narrow, oblong crown of small, spreading branches.

LEAVES.--Alternate, compound, 1-2 feet long. Leaflets usually 7, the
upper 5-9 inches long, 3-5 inches broad, larger than the lowest pair;
sessile or short-stalked; oblong-lanceolate to obovate, taper-pointed;
finely serrate; thick and firm; lustrous, dark green above, paler and
soft-pubescent beneath. Petioles stout, glabrous or pubescent, often
persistent on the branches during the winter. Foliage fragrant when
crushed.

FLOWERS.--May, after the leaves; monoecious; the staminate in pendulous,
ternate catkins 5-8 inches long, slender, yellow-green, on common
peduncles 1 inch long; scales 3-lobed, tomentose; stamens 4, with
yellow, hairy anthers; the pistillate in crowded, 2-5-flowered spikes,
tomentose; calyx 3-toothed, hairy; corolla 0; stigmas 2, light green.

FRUIT.--October; oblong to subglobose, 1-3/4-2-1/2 inches long, with very
thick, woody husk, splitting to the base; nut 4-6-ridged, with thick,
hard shell and large, sweet kernel.

WINTER-BUDS.--Terminal bud about 1 inch long, ovoid, obtuse, dark brown,
puberulous.

BARK.--Twigs orange and more or less pubescent, becoming darker in the
first winter, and finally grayish; on the trunk 1-2 inches thick, light
gray, separating into broad, thick plates 3-4 feet long, persistent on
the trunk for many years.

WOOD.--Heavy, very hard, strong, tough, close-grained, very elastic, dark
brown, with thin, whitish sapwood.

DISTRIBUTION.--Occurs in the southern portion of the Lower Peninsula, but
is rather a rare tree.

HABITAT.--Prefers deep, rich bottom-lands.

NOTES.--Rapid in growth. May be distinguished from other hickories by
orange colored branchlets.


[Illustration: Mocker Nut Hickory


   1. Winter twig, × 1.
   2. Leaf, × 1/3.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1/2.]


+JUGLANDACEAE+

+Mocker Nut Hickory+

_Carya alba (L.) K. Koch_ [_Hicoria alba (L.) Britt._] [_Carya tomentosa
Nutt._]


HABIT.--A tree 50-70 feet high, with a trunk diameter of 1-2-1/2 feet;
forming a wide crown of strong, upright branches and stout branchlets.

LEAVES.--Alternate, compound, 8-12 inches long. Leaflets usually 5-7,
sometimes 9, the upper 5-8 inches long, 3-4 inches broad; sessile,
except the terminal; oblong- to obovate-lanceolate; minutely or sometimes
coarsely serrate; thick and firm; lustrous, dark yellow-green above,
paler and more or less pubescent beneath. Petioles pubescent. Foliage
fragrant when crushed.

FLOWERS.--May, after the leaves; monoecious; the staminate in pendulous,
ternate catkins 4-5 inches long, slender, green, hairy; scales 3-lobed,
hairy; stamens 4-5, with red anthers; the pistillate in crowded,
2-5-flowered, tomentose spikes; calyx toothed, hairy; corolla 0; stigmas
2, hairy.

FRUIT.--October; globose to globose-oblong, 1-1/2-2 inches long, with
thick husk splitting nearly to the base; nut 4-ridged, red-brown, with
very thick, hard shell and small, sweet kernel.

WINTER-BUDS.--Terminal bud 1/2-3/4 inch long, broadly ovoid, red-brown,
pilose; outermost scales fall in early autumn.

BARK.--Twigs at first brown-tomentose, becoming smooth and grayish; on
the trunk thick, hard, grayish, slightly ridged by shallow, irregular
fissures, becoming rugged on very old trunks.

WOOD.--Very heavy, hard, strong, tough, close-grained, elastic, dark
brown, with thick, whitish sapwood.

DISTRIBUTION.--Southern Peninsula as far north as Grand Rapids and Flint.
Infrequent.

HABITAT.--Prefers rich, well-drained soil, but grows well in various
situations, if they are not too wet.

NOTES.--Hardy throughout its range. Difficult to transplant.


[Illustration: +Small Pignut Hickory+

   1. Winter twig, × 1.
   2. Leaf, × 1/3.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1.]


+JUGLANDACEAE+

+Small Pignut Hickory+

_Carya microcarpa Nutt._ [_Hicoria odorata (Marsh.) Sarg._] [_Hicoria
microcarpa (Nutt.) Britt._] [_Hicoria glabra, v. odorata Sarg._]


HABIT.--A tree usually 50-70 feet high, with a trunk diameter of 1-3
feet; forming an oblong or sometimes rounded crown of slender, spreading
branches.

LEAVES.--Alternate, compound, 8-12 inches long. Leaflets usually 5-7, the
upper 3-6 inches long, 2-2-1/2 inches broad; sessile, except the
terminal; oblong to ovate-lanceolate, long-pointed; sharply serrate;
thick and firm; glabrous, dark yellow-green above, lighter beneath.
Petioles long, glabrous. Foliage fragrant when crushed.

FLOWERS.--May, after the leaves; monoecious; the staminate in pendulous,
ternate catkins 3-7 inches long, slender, greenish, glabrous; stamens 4,
with orange anthers; the pistillate in 2-5-flowered spikes, 1/4 inch
long; calyx 4-toothed, hairy; corolla 0; stigmas 2, yellow.

FRUIT.--September; subglobose or globose-oblong, less than 1 inch long,
with thin husk splitting nearly to the base; nut obscurely 4-ridged,
with thin shell and small, sweet kernel.

WINTER-BUDS.--1/4-1/2 inch long, dome-shaped, red-brown, smooth.

BARK.--Twigs greenish, long-hairy, becoming reddish and finally gray;
thick, hard and grayish on the trunk, divided by shallow fissures into
narrow plates, and more or less shaggy.

WOOD.--Heavy, hard, strong, tough, close-grained, elastic, dark brown,
with thick, whitish sapwood.

DISTRIBUTION.--Confined to the most southern portions of the Lower
Peninsula.

HABITAT.--Prefers well-drained slopes and hillsides.

NOTES.--Resembles _C. glabra_, but the nut is much smaller.


[Illustration: +Pignut Hickory+

   1. Winter twig, × 1.
   2. Leaf, × 1/4.
   3. Flowering branchlet, × 1.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 2/3.]


+JUGLANDACEAE+

+Pignut Hickory+

_Carya glabra (Mill.) Spach._ [_Hicoria glabra (Mill.) Britt._] [_Carya
porcina Nutt._]


HABIT.--A tree usually 50-65 feet high, with a trunk diameter of 1-3
feet; forming a low, rather narrow, open crown of slender, often
contorted branches.

LEAVES.--Alternate, compound, 8-12 inches long. Leaflets usually 5-7, the
upper 3-6 inches long, 2-2-1/2 inches broad; subsessile, except the
terminal; oblong to obovate-lanceolate, taper-pointed; sharply serrate;
thick and firm; glabrous, dark yellow-green above, paler beneath.
Petioles long, slender, glabrous or pubescent. Foliage fragrant when
crushed.

FLOWERS.--May, after the leaves; monoecious; the staminate in pendulous,
ternate catkins 3-7 inches long, slender, yellow-green, tomentose;
scales 3-lobed, nearly glabrous; stamens 4, with orange anthers; the
pistillate in crowded, 2-5-flowered spikes, 1/4 inch long; calyx
4-toothed, hairy; corolla 0; stigmas 2, yellow.

FRUIT.--October; variable in size and shape, 1-1/2-2 inches long, with
thin husk splitting half-way and sometimes nearly to the base; nut
obscurely 4-ridged, with thin or thick, hard shell and small, sweet or
slightly bitter kernel which is hard to remove.

WINTER-BUDS.--Terminal bud 1/4-1/2 inch long, dome-shaped, greenish or
grayish, smooth or finely downy.

BARK.--Twigs greenish, nearly glabrous, becoming reddish, and finally
grayish; thick, hard and grayish on the trunk, with a firm, close
surface divided by small fissures and sometimes broken into plates.

WOOD.--Heavy, hard, very strong, tough, close-grained, elastic, dark
brown, with thick, whitish sapwood.

DISTRIBUTION.--Occurs only in the extreme southern portion of the Lower
Peninsula. Common within its range.

HABITAT.--Prefers deep, rich loam, but grows in any well-drained soil;
dry ridges and hillsides.

NOTES.--Hardy and desirable for ornamental purposes. Difficult to
transplant. Not adapted to street use.


[Illustration: +Bitternut Hickory+

   1. Winter twig, × 1.
   2. Leaf, × 1/3.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1.]


+JUGLANDACEAE+

+Bitternut Hickory+

_Carya cordiformis (Wang.) K. Koch_ [_Hicoria minima (Marsh.) Britt._]
[_Carya amara Nutt._]


HABIT.--A tall, slender tree 50-75 feet high, with a trunk diameter of
1-2-1/2 feet; forming a broad crown of slender, stiff, upright branches,
widest near the top.

LEAVES.--Alternate, compound, 6-10 inches long. Leaflets 5-11, the upper
4-6 inches long and one-fourth as broad; sessile, except the terminal;
lanceolate to oblong-lanceolate, long-pointed; coarsely serrate; thin
and firm; glabrous, bright green above, paler and more or less downy
beneath. Petioles slender, hairy. Foliage fragrant when crushed.

FLOWERS.--May, after the leaves; monoecious; the staminate slightly
pubescent, in pendulous, ternate catkins 3-4 inches long, on a common
peduncle about 1 inch long; scales 3-lobed, hairy; stamens 4, with
bearded, yellow anthers; the pistillate in 2-5-flowered spikes 1/2 inch
long, scurfy-tomentose; calyx 4-lobed, pubescent; corolla 0; stigmas 2,
greenish.

FRUIT.--October; obovate to globular, about 1 inch long, coated with
yellow, scurfy pubescence, with very thin husk splitting half-way to the
base, with sutures winged at the top; nut quite smooth, with thin shell
and small, bitter kernel.

WINTER-BUDS.--Terminal bud about 3/4 inch long, long-pointed, flattish,
granular-yellow; lateral buds more or less 4-angled.

BARK.--Twigs greenish and more or less downy, becoming brownish, and
finally grayish; gray, close, smooth on the trunk, often reticulately
ridged, but rarely broken into plates.

WOOD.--Heavy, very hard, strong, tough, close-grained, dark brown, with
thick, lighter colored sapwood.

DISTRIBUTION.--Of common occurrence in the southern half of the Lower
Peninsula.

HABITAT.--Prefers a rich, loamy or gravelly soil; low, wet woods; along
the borders of streams; but also found on high, dry uplands.

NOTES.--Grows most rapidly of all the hickories, but is apt to show dead
branches. Should be propagated from the seed, as it is not easily
transplanted.


[Illustration: +Hornbeam. Ironwood+

   1. Winter twig, × 1/2.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1/2.]


+BETULACEAE+

+Hornbeam. Ironwood+

_Ostrya virginiana (Mill.) K. Koch_


HABIT.--A small tree usually 20-30 feet high, with a trunk diameter of
8-12 inches; forming a broad, rounded crown of many long, slender
branches and a slender, stiff spray.

LEAVES.--Alternate, simple, 3-5 inches long, about one-half as broad;
oblong-ovate; sharply doubly serrate; thin and very tough; dull, dark
green above, paler and more or less pubescent beneath; petioles short,
slender, pubescent.

FLOWERS.--April-May, with the leaves; monoecious; the staminate in
drooping, cylindrical catkins from wood of the previous season, usually
in threes; stamens 3-14, crowded on a hairy torus; the pistillate in
erect, lax catkins on the season's shoots, usually in pairs, each flower
inclosed in a hairy, sac-like involucre.

FRUIT.--September; strobiles, resembling clusters of hops, 1-2 inches
long, borne on slender, hairy stems; nuts small and flat, inclosed by
sac-like involucres.

WINTER-BUDS.--Terminal bud absent; lateral buds 1/8-1/4 inch long, ovoid,
acute, red-brown.

BARK.--Twigs at first light green, becoming lustrous, red-brown, and
finally dull dark brown; thin, gray-brown on the trunk, very narrowly
and longitudinally ridged.

WOOD.--Heavy, very strong and hard, tough, close-grained, durable, light
red-brown, with thick, whitish sapwood.

DISTRIBUTION.--Common throughout the entire state.

HABITAT.--Prefers dry, gravelly slopes and ridges.

NOTES.--Often grows in shade of other trees. Not easily transplanted.
Rather slow of growth. Too small for street use.


[Illustration: +Blue Beech. Water Beech+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1/2.]


+BETULACEAE+

+Blue Beech. Water Beech+

_Carpinus caroliniana Walt._


HABIT.--Usually a low, bushy tree or large shrub, 10-30 feet high, with a
trunk diameter of 6-12 inches; trunk short, usually fluted; slender
zigzag branches and a fine spray form a close, flat-topped crown.

LEAVES.--Alternate, simple, 2-4 inches long and one-half as broad; ovate
to oval, long-pointed; sharply doubly serrate; thin and firm; dull green
above, lighter beneath, turning scarlet and orange in autumn; petioles
short, slender, hairy.

FLOWERS.--May, after the leaves; monoecious; apetalous; the staminate
catkins 1-1-1/2 inches long, their scales greenish, boat-shaped, each
bearing 3-20 stamens; the pistillate catkins 1/2-3/4 inch long, their
scales hairy, greenish, each bearing 2 pistils with long, scarlet
styles.

FRUIT.--Ripens in midsummer, but often remains on the tree long after the
leaves have fallen; in loose, terminal strobiles; involucre
halberd-shaped, inclosing a small, ovate, brownish nut.

WINTER-BUDS.--Terminal bud absent; lateral buds 1/8 inch long,
narrow-ovoid, acute, puberulous, brownish.

BARK.--Twigs pale green, hairy, becoming lustrous, dark red the first
winter; trunk and large limbs thin, smooth, close, dark bluish gray,
often mottled with lighter or darker patches.

WOOD.--Heavy, hard, tough, very strong, close-grained, light brown, with
thick, whitish sapwood.

DISTRIBUTION.--Common throughout the state.

HABITAT.--Prefers a deep, rich, moist soil along the borders of streams
and swamps. Often found in drier situations in the shade of other trees.

NOTES.--Propagated from seed. Not easily transplanted. Slow of growth.
Seldom found in masses.


+SUMMER KEY TO THE SPECIES OF BETULA+

   a. Bark of trunk white, separating freely into thin, papery
   layers; twigs without wintergreen taste; leaves usually
   solitary, not aromatic. _B. alba papyrifera_, p. 91.

   aa. Bark of trunk not white, usually dark colored, not
   separating freely into papery layers; twigs with more or less
   wintergreen taste; leaves solitary or in pairs, aromatic.

   b. Bark dirty-yellow, breaking into strips more or less curled
   at the edges; leaves solitary or in pairs, slightly aromatic;
   twigs with slight wintergreen taste. _B. lutea_, p. 89.

   bb. Bark dark red-brown, cleaving off in thick, irregular
   plates (resembles bark of Black Cherry); leaves in pairs,
   strongly aromatic; twigs with strong wintergreen taste. _B.
   lenta_, p. 87.


+WINTER KEY TO THE SPECIES OF BETULA+

   a. Bark of trunk white, separating freely into thin, papery
   layers; twigs without wintergreen taste. _B. alba papyrifera_,
   p. 91.

   aa. Bark of trunk not white, usually dark colored, not
   separating into papery layers; twigs with more or less
   wintergreen taste.

   b. Bark dirty-yellow, breaking into strips more or less curled
   at the edges; twigs with slight wintergreen taste. _B. lutea_,
   p. 89.

   bb. Bark dark red-brown, cleaving off in thick, irregular
   plates (resembles bark of Black Cherry); twigs with strong
   wintergreen taste. _B. lenta_, p. 87


[Illustration: +Sweet Birch. Black Birch. Cherry Birch+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruiting branchlet, × 1/2.
   8. Fruit, enlarged.]


+BETULACEAE+

+Sweet Birch. Black Birch. Cherry Birch+

_Betula lenta L._[F]


HABIT.--A medium-sized tree 70-80 feet high, with a trunk diameter of 1-3
feet; slender, wide-spreading, pendulous branches, forming a narrow,
rounded, open crown.

LEAVES.--Alternate in pairs, simple, 3-4 inches long and one-half as
broad; outline variable, ovate to oblong-ovate; sharply doubly serrate,
with slender, incurved teeth; dull, dark green above, light yellow-green
beneath; petioles short, stout, hairy, deeply grooved above; aromatic.

FLOWERS.--April, before the leaves; monoecious; the staminate catkins 3-4
inches long, slender, pendent, yellowish; the pistillate catkins 1/2-3/4
inch long, erect or suberect, greenish.

FRUIT.--Ripens in autumn; sessile, glabrous, erect strobiles, 1-1-1/2
inches long and half as thick; scales glabrous; nuts slightly broader
than their wings.

WINTER-BUDS.--Terminal bud absent; lateral buds about 1/4 inch long,
conical, sharp-pointed, red-brown, divergent.

BARK.--Twigs light green, becoming lustrous, red-brown in their first
winter; very dark on old trunks, cleaving off in thick, irregular
plates. Resembles bark of Black Cherry. Inner bark aromatic, spicy.

WOOD.--Heavy, very hard and strong, close-grained, dark red-brown, with
thin, lighter colored sapwood.

DISTRIBUTION.--Scattered throughout the state; rare in the south, more
abundant and of larger size in the north.

HABITAT.--Grows in any situation, but prefers moist, rocky slopes and
rich uplands.

NOTES.--Hardy throughout its range. Easily transplanted.


[Illustration: +Yellow Birch. Gray Birch+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruiting branchlet, × 1/2.
   8. Fruit, × 10.]


+BETULACEAE+

+Yellow Birch. Gray Birch+

_Betula lutea Michx. f._


HABIT.--A tree 60-80 feet high and 2-4 feet in trunk diameter; numerous
slender, pendulous branches form a broad, open, rounded crown.

LEAVES.--Alternate, solitary or in pairs, simple, 3-5 inches long and
one-half as broad; ovate to oblong-ovate; sharply doubly serrate; dull
dark green above, yellow-green beneath; petioles short, slender,
grooved, hairy; slightly aromatic.

FLOWERS.--April, before the leaves; monoecious; the staminate catkins 3-4
inches long, slender, pendent, purplish yellow; the pistillate catkins
sessile or nearly so, erect, almost 1 inch long, greenish.

FRUIT.--Ripens in autumn; sessile or short-stalked, erect, glabrous
strobiles, about 1 inch long and half as thick; scales downy on the back
and edges; nut about as broad as the wing.

WINTER-BUDS.--Terminal bud absent; lateral buds about 1/4 inch long,
conical, acute, chestnut-brown, more or less appressed; bud-scales more
or less pubescent.

BARK.--Twigs, branches and young stems smooth, very lustrous, silvery
gray or light orange; becoming silvery yellow-gray as the trunk expands
and breaking into strips more or less curled at the edges; old trunks
becoming gray or blackish, dull, deeply and irregularly fissured into
large, thin plates; somewhat aromatic, slightly bitter.

WOOD.--Heavy, very strong and hard, close-grained, light brown tinged
with red, with thin, whitish sapwood.

DISTRIBUTION.--Throughout the state, but more abundant and of larger size
northward.

HABITAT.--Prefers rich, moist uplands, but grows in wet or dry
situations.

NOTES.--One of the largest deciduous-leaved trees of Michigan. Easily
transplanted, but not desirable as a street tree.


[Illustration: +Paper Birch. Canoe Birch. White Birch+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruiting branchlet, × 1/2.
   8. Fruit, × 3-1/2.]


+BETULACEAE+

+Paper Birch. Canoe Birch. White Birch+

_Betula alba papyrifera_ (_Marsh._) _Spach_. [_Betula papyrifera
Marsh._]


HABIT.--A tree 50-75 feet high, with a trunk diameter of 1-3 feet,
forming in youth a compact, pyramidal crown of many slender branches,
becoming in old age a long, branchless trunk with a broad, open crown,
composed of a few large limbs ascending at an acute angle, with almost
horizontal branches and a slender, flexible spray.

LEAVES.--Alternate, simple, 2-3 inches long, 1-1/2-2 inches broad; ovate;
coarsely, more or less doubly serrate; thick and firm; glabrous, dark
green above, lighter beneath, covered with minute black glands; petioles
stout, yellow, glandular, glabrous or pubescent.

FLOWERS.--April, before the leaves; monoecious; the staminate catkins
clustered or in pairs, 3-4 inches long, slender, pendent, brownish; the
pistillate catkins about 1-1/2 inches long, slender, erect or spreading,
greenish; styles bright red.

FRUIT.--Ripens in autumn; long-stalked, cylindrical, glabrous, drooping
strobiles, about 1-1/2 inches long; scales hairy on the margin; nut
narrower than its wing.

WINTER-BUDS.--Terminal bud absent; lateral buds 1/4 inch long,
narrow-ovoid, acute, flattish, slightly resinous, usually divergent.

BARK.--Twigs dull red, becoming lustrous orange-brown; bark of trunk and
large limbs cream-white and lustrous on the outer surface, bright orange
on the inner, separating freely into thin, papery layers, becoming
furrowed and almost black near the ground.

WOOD.--Light, hard, strong, tough, very close-grained, light brown tinged
with red, with thick, whitish sapwood.

DISTRIBUTION.--Lansing and northward. Common in central Michigan as a
small tree. Of larger size in the Upper Peninsula.

HABITAT.--Prefers rich, moist hillsides; borders of streams, lakes and
swamps; but is also found in drier situations.

NOTES.--A rapid grower in youth. The bark is used by the Indians and
woodsmen for canoes, wigwams, baskets, torches, etc.


[Illustration: +Beech. White Beech+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1.
   4. Flowering branchlet, × 3/4.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Bur, opened, × 1.
   8. Nut, × 1.]


+FAGACEAE+

+Beech. White Beech+

_Fagus grandifolia Ehrh._ [_Fagus atropunicea_ (_Marsh._) _Sudw._]
[_Fagus ferruginea Ait._] [_Fagus americana Sweet_]


HABIT.--A beautiful tree, rising commonly to a height of 50-75 feet, with
a trunk diameter of 2-4 feet; in the forest, tall and slender, with
short branches forming a narrow crown, in the open with a short, thick
trunk and numerous slender, spreading branches, forming a broad,
compact, rounded crown.

LEAVES.--Alternate, simple, 3-5 inches long, one-half as broad;
oblong-ovate, acuminate; coarsely serrate, a vein terminating in each
tooth; thin; dark blue-green above, light yellow-green and very lustrous
beneath; petioles short, hairy.

FLOWERS.--April-May, with the leaves; monoecious; the staminate in
globose heads 1 inch in diameter, on long, slender, hairy peduncles,
yellow-green; calyx campanulate, 4-7-lobed, hairy; corolla 0; stamens
8-10; the pistillate on short, hairy peduncles in 2-flowered clusters
surrounded by numerous awl-shaped, hairy bracts; calyx urn-shaped,
4-5-lobed; corolla 0; ovary 3-celled; styles 3.

FRUIT.--Ripens in autumn; a prickly bur borne on stout, hairy peduncles,
persistent on the branch after the nuts have fallen; nuts usually 3, 3/4
inch long, sharply tetrahedral, brownish; sweet and edible.

WINTER-BUDS.--Nearly 1 inch long, very slender, cylindrical, gradually
taper-pointed, brownish, puberulous.

BARK.--Twigs lustrous, olive-green, finally changing through brown to
ashy gray; close, smooth, steel-gray on the trunk, often mottled by
darker blotches and bands.

WOOD.--Hard, tough, strong, very close-grained, not durable, difficult to
season, light or dark red, with thin, whitish sapwood.

DISTRIBUTION.--Common in the Lower Peninsula, especially in the northern
portions; rare in the Upper Peninsula.

HABITAT.--Prefers deep, rich, well-drained loam, but is found and does
well on a great variety of soils.

NOTES.--Hardy throughout its range. Desirable for landscape work because
of its clean trunk and limbs, deep shade, and freedom from insect pests.
Often suckers from the roots.


[Illustration: +Chestnut+

   1. Winter twig, × 1.
   2. Leaf, × 1/2.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Prickly bur, opened, × 1/2.
   7. Nut, × 1/2.]


+FAGACEAE+

+Chestnut+

_Castanea dentata_ (_Marsh._) _Borkh._ [_Castanea vesca, v. americana
Michx._] [_Castanea sativa, v. americana Sarg._]


HABIT.--A tree 60-80 feet high, forming a short, straight trunk 2-4 feet
in diameter, divided not far above the ground into several stout,
horizontal limbs and forming a broad, open, rounded crown.

LEAVES.--Alternate, simple, 6-8 inches long, 2-3 inches broad;
oblong-lanceolate, long-pointed at the apex; coarsely serrate with
stout, incurved, glandular teeth; thin; dull yellow-green above, lighter
beneath, glabrous; petioles short, stout, puberulous.

FLOWERS.--June-July, after the leaves; monoecious; the staminate catkins
6-8 inches long, slender, puberulous, bearing 3-7-flowered cymes of
yellow-green flowers; calyx 6-cleft, pubescent; stamens 10-20; the
androgynous catkins 2-1/2-5 inches long, puberulous, bearing 2-3 prickly
involucres of pistillate flowers near their base; calyx campanulate,
6-lobed; styles 6.

FRUIT.--Ripens in autumn; round, thick, prickly burs, about 2 inches in
diameter, containing 1-3 nuts; nuts compressed, brownish, coated with
whitish down at the apex; sweet and edible.

WINTER-BUDS.--Terminal bud absent; lateral buds 1/4 inch long, ovoid,
acute, brownish.

BARK.--Twigs lustrous, yellow-green, becoming olive-green and finally
dark brown; old trunks gray-brown, with shallow fissures and broad, flat
ridges.

WOOD.--Light, soft, coarse-grained, weak, easily split, very durable in
contact with the soil, red-brown, with very thin, lighter colored
sapwood.

DISTRIBUTION.--South-eastern Michigan, as far north as St. Clair County.
Abundant in eastern Monroe County and Wayne County.

HABITAT.--Pastures; hillsides; glacial drift; well-drained, gravelly or
rocky soil.

NOTES.--A rapid grower and living to a great age. Difficult to
transplant. Subject to a disease which threatens extermination in this
country.


+SUMMER KEY TO THE SPECIES OF QUERCUS+

   a. Leaves deeply cut or lobed.

   b. Leaf-lobes acute, bristle-tipped; fruit maturing in the
   second season.

   c. Lower surface of leaves more or less pubescent.

   d. Leaf-lobes usually 7; buds hoary-tomentose; bark of trunk
   deeply furrowed and scaly; inner bark yellow; cup-scales of
   acorn hoary-pubescent; nut ovoid; large tree, common in
   Michigan. _Q. velutina_, p. 117.

   dd. Leaf-lobes usually 3 (at apex of the leaf only); buds
   rusty-hairy; bark of trunk divided into nearly square plates;
   inner bark not yellow; cup-scales of acorn rusty-tomentose;
   nut subglobose; shrubby tree, rare in Michigan. _Q.
   marilandica_, p. 119.

   cc. Lower surface of leaves glabrous or nearly so.

   d. Cup of acorn top-shaped or cup-shaped, inclosing one-third
   to one-half of the nut.

   e. Kernel of nut yellow; buds glabrous, lustrous, slightly
   angular; inner bark of trunk yellow; trunk provided with pins
   or stubs of dead branches near the ground. _Q. ellipsoidalis_, p. 115.

   ee. Kernel of nut whitish; buds pubescent above the middle,
   not angular; inner bark of trunk red; trunk not provided with
   pins or stubs of branches near the ground. _Q. coccinea_, p. 113.

   dd. Cup of acorn saucer-shaped, inclosing only the base of the
   nut.

   e. Upper surface of leaves usually lustrous, especially on the
   lower branches; lowermost branches of trees growing in the
   open drooping nearly to the ground; nut about 1/2 inch long
   _Q. palustris_, p. 111.

   ee. Upper surface of leaves usually dull; lowermost branches
   of trees growing in the open not drooping; nut about 1 inch
   long. _Q. rubra_, p. 109.

   bb. Leaf-lobes rounded, not bristle-tipped; fruit maturing in
   the first season.

   c. Leaves cut nearly to the midrib by a pair of deep sinuses
   near the middle of the leaf; branches corky-ridged; nut
   1/2-1-1/2 inches long, deeply seated in a large, conspicuously
   fringed cup. _Q. macrocarpa_, p. 103.

   cc. Leaves not cut by a pair of deep sinuses; branches not
   corky-ridged; nut about 3/4 inch long, about one-fourth
   covered by a thin, tomentose, warty cup. _Q. alba_, p. 101.

   aa. Leaves not deeply cut nor lobed.

   b. Margin of leaf entire to sinuate-crenate, but not toothed;
   acorns on stalks 1/2-4 inches long.

   c. Margin of leaf entire, or only slightly undulate; acorns on
   peduncles 1/2 inch long, the nut about 1/2 inch long; bark on
   branches not breaking into large, papery scales. _Q.
   imbricaria_, p. 121.

   cc. Margin of leaf sinuate-crenate, rarely lobed; acorns on
   stems 1-4 inches long, the nut about 1 inch long; bark on
   branches breaking into large, papery scales which curl back
   _Q. bicolor_, p. 105.

   bb. Margin of leaf coarsely toothed; acorns sessile or on
   stalks less than 1/2 inch long. _Q. muhlenbergii_, p. 107.


+WINTER KEY TO THE SPECIES OF QUERCUS+

   a. Terminal buds usually about 1/8 inch long.

   b. Twigs thick-tomentose; entire bud pale-pubescent; branches
   corky-ridged; cup of acorn conspicuously fringed at the rim.
   [1][G] _Q. macrocarpa_, p. 103.

   bb. Twigs glabrous; buds glabrous, or only slightly or
   partially pubescent; branches without corky ridges; cup of
   acorn not conspicuously fringed at the rim.

   c. Bark on branches breaking into large, papery scales which
   curl back; buds pilose above the middle; acorns on pubescent
   stems 1-4 inches long. [1] _Q. bicolor_, p. 105.

   cc. Bark on branches not breaking into large, papery scales;
   buds glabrous; acorns sessile or very short-stalked.

   d. Bark of trunk ash-gray or nearly white, flaky; acorns
   maturing in autumn of first season; kernel of nut sweet.

   e. Buds conical, acute; bud-scales scarious on the margins;
   nut white-downy at the apex. [1] _Q. muhlenbergii_, p. 107.

   ee. Buds broadly ovoid, obtuse; bud-scales not scarious on the
   margins; nut not white-downy at the apex. [1] _Q. alba_, p.
   101.

   dd. Bark of trunk light to dark brown, smoothish or only
   slightly fissured; acorns maturing in autumn of second season;
   kernel of nut bitter.

   e. Lateral buds widely divergent; bud-scales scarious on the
   margins; lowermost branches of trees growing in the open not
   drooping nearly to the ground. [2] _Q. imbricaria_, p. 121.

   ee. Lateral buds more or less appressed; bud-scales not
   scarious on the margins; lowermost branches of trees growing
   in the open drooping nearly to the ground. [2] _Q. palustris_,
   p. 111.

   aa. Terminal buds usually about 1/4 inch long (slightly
   smaller in _Q. ellipsoidalis_).

   b. Buds conspicuously hairy or tomentose.

   c. Buds rusty-hairy, acute at the apex; cup-scales of acorn
   rusty-tomentose; inner bark of trunk not yellow; shrubby tree,
   rare in Michigan. [2] _Q. marilandica_, p. 119.

   cc. Buds hoary-tomentose, obtuse at the apex; cup-scales of
   acorn hoary-pubescent; inner bark of trunk yellow; large tree,
   common in Michigan. [2] _Q. velutina_, p. 117.

   bb. Buds glabrous, or pubescent only above the middle.

   c. Buds strictly glabrous throughout, lustrous; inner bark of
   trunk yellow or whitish.

   d. Buds obtuse at the apex; trunk provided with pins or stubs
   of dead branches near the ground; inner bark of trunk yellow;
   nut 1/2-3/4 inch long, inclosed for one-third to one-half of
   its length in a top-shaped cup; kernel of nut yellow. [2] _Q.
   ellipsoidalis_, p. 115.

   dd. Buds acute at the apex; trunk not provided with pins or
   stubs of branches near the ground; inner bark of trunk
   whitish; nut about 1 inch long, inclosed only at the base by a
   shallow, saucer-shaped cup; kernel of nut white. [2] _Q.
   rubra_, p. 109.

   cc. Buds pale-pubescent above the middle, but usually glabrous
   below, not lustrous; inner bark of trunk red. [2] _Q.
   coccinea_, p. 113.


[Illustration: +White Oak+

   1. Winter twig, × 2.
   2. Leaf, × 1/2.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1.]


+FAGACEAE+

+White Oak+

_Quercus alba L._


HABIT.--A large tree 60-80 feet high, with a trunk diameter of 2-4 feet;
forming a short, thick trunk with stout, horizontal, far-reaching limbs,
more or less gnarled and twisted in old age, and a broad, open crown.

LEAVES.--Alternate, simple, 5-9 inches long, about one-half as broad;
obovate to oblong; 5-9-lobed, some with broad lobes and shallow sinuses,
others with narrow lobes and deep, narrow sinuses, the lobes usually
entire; thin and firm; glabrous, bright green above, pale or glaucous
beneath; often persistent on the tree through the winter.

FLOWERS.--May, with the leaves; monoecious; the staminate in hairy
catkins 2-3 inches long; the pistillate sessile or short-peduncled,
reddish, tomentose; calyx campanulate, 6-8-lobed, yellow, hairy; corolla
0; stamens 6-8, with yellow anthers; stigmas red.

FRUIT.--Autumn of first season; sessile or short-stalked acorns; cup with
small, brown-tomentose scales, inclosing one-fourth of the nut; nut
oblong-ovoid, rounded at the apex, about 3/4 inch long, light brown;
kernel sweet and edible.

WINTER-BUDS.--Terminal bud 1/8 inch long, broadly ovoid, obtuse; scales
smooth, dark red-brown.

BARK.--Twigs at first bright green, tomentose, later reddish, and finally
ashy gray; thick, light gray or whitish on old trunks, shallowly
fissured into broad, flat ridges.

WOOD.--Very heavy, strong, hard, tough, close-grained, durable, light
brown, with thin, light brown sapwood.

DISTRIBUTION.--Rare in the Upper Peninsula, common in the Lower
Peninsula, especially in the lower half.

HABITAT.--Grows well in all but very wet soils, in all open exposures.

NOTES.--Slow and even of growth. Difficult to transplant.


[Illustration: +Bur Oak+

   1. Winter twig, × 2.
   2. Leaf, × 1/3.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1.]


+FAGACEAE+

+Bur Oak+

_Quercus macrocarpa Michx._


HABIT.--A large tree 60-80 feet high, with a trunk 2-4 feet in diameter;
great, spreading branches form a broad, rugged crown.

LEAVES.--Alternate, simple, 6-10 inches long and one-half as broad;
obovate to oblong, wedge-shaped at the base; crenately lobed, usually
cut nearly to the midrib by two opposite sinuses near the middle; thick
and firm; dark green and shining above, pale-pubescent beneath; petioles
short, stout.

FLOWERS.--May, with the leaves; monoecious; the staminate in slender,
hairy catkins 4-6 inches long; the pistillate sessile or short-stalked,
reddish, tomentose; calyx 4-6-lobed, yellow-green, downy; corolla 0;
stamens 4-6, with yellow anthers; stigmas bright red.

FRUIT.--Autumn of first season; sessile or short-stalked acorns; very
variable in size and shape; cup typically deep, cup-shaped, tomentose,
fringed at the rim, inclosing one-third or all of the nut; nut
broad-ovoid, 1/2-1-1/2 inches long, brownish, pubescent; kernel white,
sweet and edible.

WINTER-BUDS.--Terminal bud 1/8 inch long, broadly ovoid or conical,
red-brown, pale-pubescent.

BARK.--Twigs yellow-brown, thick-tomentose, becoming ash-gray or
brownish; branches with corky ridges; thick and gray-brown on the trunk,
deeply furrowed.

WOOD.--Heavy, hard, strong, tough, close-grained, very durable, brownish,
with thin, pale sapwood.

DISTRIBUTION.--Common throughout both peninsulas.

HABITAT.--Prefers rich, moist soil; bottom-lands; but is tolerant of many
soils.

NOTES.--Rather slow of growth. Difficult to transplant.


[Illustration: +Swamp White Oak. Swamp Oak+

   1. Winter twig, × 2.
   2. Leaf, × 1/2.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1.]


+FAGACEAE+

+Swamp White Oak. Swamp Oak+

_Quercus bicolor Willd._ [_Quercus platanoides (Lam.) Sudw._]


HABIT.--A large tree 50-70 feet high, with a trunk diameter of 2-3 feet;
forming a rather open, rugged crown of tortuous, pendulous branches and
short, stiff, bushy spray.

LEAVES.--Alternate, simple, 5-7 inches long, 3-5 inches broad; obovate to
oblong-obovate; coarsely sinuate-crenate or shallow-lobed; thick and
firm; dark green and shining above, whitish and more or less tomentose
beneath; petioles stout, about 1/2 inch long.

FLOWERS.--May, with the leaves; monoecious; the staminate in hairy
catkins 3-4 inches long; the pistillate tomentose, on long, tomentose
peduncles, in few-flowered spikes; calyx deeply 5-9-lobed, yellow-green,
hairy; corolla 0; stamens 5-8, with yellow anthers; stigmas bright red.

FRUIT.--Autumn of first season; acorns on pubescent stems 1-4 inches
long, usually in pairs; cup cup-shaped, with scales somewhat loose (rim
often fringed), inclosing one-third of the nut; nut ovoid, light brown,
pubescent at the apex, about 1 inch long; kernel white, sweet, edible.

WINTER-BUDS.--Terminal bud 1/8 inch long, broadly ovoid to globose,
obtuse; scales light brown, pilose above the middle.

BARK.--Twigs at first lustrous, green, becoming red-brown, finally dark
brown and separating into large, papery scales which curl back; thick,
gray-brown on the trunk, deeply fissured into broad, flat, scaly ridges.

WOOD.--Heavy, hard, strong, tough, coarse-grained, light brown, with
thin, indistinguishable sapwood.

DISTRIBUTION.--Southern half of Lower Peninsula.

HABITAT.--Prefers moist, rich soil bordering swamps and along streams.

NOTES.--Fairly rapid in growth and reasonably easy to transplant.


[Illustration: +Chinquapin Oak. Chestnut Oak. Yellow Oak+

   1. Winter twig, × 2.
   2. Leaf, × 1/2.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1.]


+FAGACEAE+

+Chinquapin Oak. Chestnut Oak. Yellow Oak+

_Quercus muhlenbergii Engelm._ [_Quercus acuminata (Michx.) Houba_]


HABIT.--A medium-sized tree 40-50 feet high, with a trunk diameter of 1-3
feet; erect, somewhat short branches form a narrow, rounded crown.

LEAVES.--Alternate, simple, 4-7 inches long, 1-4 inches broad;
oblong-lanceolate to obovate; coarsely toothed; thick and firm;
lustrous, yellow-green above, pale-pubescent beneath; petioles slender,
about 1 inch long.

FLOWERS.--May, with the leaves; monoecious; the staminate in hairy
catkins 3-4 inches long; the pistillate sessile or in short spikes,
hoary-tomentose; calyx campanulate, 5-8-lobed, yellow, hairy; corolla 0;
stamens 5-8, with yellow anthers; stigmas red.

FRUIT.--Autumn of first season; sessile or short-stalked acorns; cup with
small scales, hoary-tomentose, inclosing one-half of the nut; nut ovoid,
about 3/4 inch long, light brown; kernel sweet, sometimes edible.

WINTER-BUDS.--Terminal bud 1/8 inch long, conical, acute; scales
chestnut-brown, scarious on the margin.

BARK.--Twigs greenish at first, becoming gray-brown, finally gray or
brown; thin, silvery gray or ash colored and flaky on the trunk.

WOOD.--Heavy, very hard, strong, close-grained, durable, dark brown, with
thin, pale brown sapwood.

DISTRIBUTION.--Confined to the southern half of the Lower Peninsula.

HABITAT.--Prefers a limestone soil; dry hillsides; rich bottom-lands;
rocky river-banks.

NOTES.--Grows uniformly until maturity. Leaves resemble those of the
Chestnut. A form which differs from the type in having broader, obovate
leaves broadest above the middle and a flaky bark has been described and
named _Quercus Alexanderi Britton_.


[Illustration: +Red Oak+

   1. Winter twig, × 1.
   2. Leaf, × 1/2.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1.]


+FAGACEAE+

+Red Oak+

_Quercus rubra L._


HABIT.--A large tree 70-80 feet high, with a trunk diameter of 2-4 feet;
forming a broad, rounded crown of a few large, wide-spreading branches
and slender branchlets.

LEAVES.--Alternate, simple, 5-9 inches long, 4-6 inches broad; oval to
obovate; 5-11-lobed with coarse-toothed, bristle-tipped lobes tapering
from broad bases and wide, oblique, rounded sinuses; thin and firm; dull
dark green above, paler beneath; petioles stout, 1-2 inches long.

FLOWERS.--April-May, when the leaves are half grown; monoecious; the
staminate in hairy catkins 4-5 inches long; the pistillate on short,
glabrous peduncles; calyx 4-5-lobed, greenish; corolla 0; stamens 4-5,
with yellow anthers; stigmas long, spreading, bright green.

FRUIT.--Autumn of second season; sessile or short-stalked acorns; cup
shallow, saucer-shaped, inclosing only the base of the nut; scales
closely appressed, more or less glossy, puberulous, bright red-brown;
nut oblong-ovoid with a broad base, about 1 inch long, red-brown; kernel
white, very bitter.

WINTER-BUDS.--Terminal bud 1/4 inch long, ovoid, acute, light brown,
smooth.

BARK.--Twigs lustrous, green, becoming reddish, finally dark brown; young
trunks smooth, gray-brown; old trunks darker, shallowly fissured into
thin, firm, broad ridges; inner bark light red, not bitter.

WOOD.--Heavy, hard, strong, coarse-grained, light red-brown, with thin,
darker colored sapwood.

DISTRIBUTION.--Southern portion of Lower Peninsula as far north as
Roscommon County.

HABITAT.--Prefers rich, moist loam; glacial drift; stream-banks. Grows
well in all well-drained soils.

NOTES.--Grows rapidly. A good street tree.


[Illustration: +Pin Oak+

   1. Winter twig, × 3.
   2. Leaf, × 1/2.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1.]


+FAGACEAE+

+Pin Oak+

_Quercus palustris Muench._


HABIT.--A medium-sized tree 40-50 feet high, with a trunk diameter of 1-2
feet; forming an oblong or pyramidal crown of many upright, spreading
branches, the lowermost drooping nearly to the ground.

LEAVES.--Alternate, simple, 4-6 inches long, 2-4 inches broad; obovate to
ovate; 5-7-lobed by deep, wide, rounded sinuses, the lobes few-toothed,
bristle-tipped; thin and firm; very lustrous, dark green above, paler
beneath; petioles slender.

FLOWERS.--May, with the leaves; monoecious; the staminate in hairy
catkins 2-4 inches long; the pistillate tomentose, borne on short,
tomentose peduncles; calyx 4-5-lobed, hairy; corolla 0; stamens 4-5,
with yellow anthers; stigmas recurved, bright red.

FRUIT.--Autumn of second season; sessile or short-stalked acorns; cup
saucer-shaped with scales closely appressed, dark red-brown, inclosing
only the base of the nut; nut nearly hemi-spherical, about 1/2 inch in
diameter, light brown; kernel bitter.

WINTER-BUDS.--Terminal bud 1/8 inch long, ovoid or conical, acute, light
brown, smooth.

BARK.--Twigs dark red and tomentose at first, becoming lustrous, green,
finally gray-brown; thick, gray-brown and smoothish on the trunk.

WOOD.--Heavy, hard, strong, coarse-grained, light brown, with thin,
darker colored sapwood.

DISTRIBUTION.--Confined to the most southern portions of the Lower
Peninsula.

HABITAT.--Prefers moist, rich soil; river-bottoms; borders of swamps.

NOTES.--Grows rapidly and uniformly. Easily transplanted. The tiny
branchlets at a distance give the impression of the tree being full of
pins.


[Illustration: +Scarlet Oak+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1.]


+FAGACEAE+

+Scarlet Oak+

_Quercus coccinea Muench._


HABIT.--A tree 40-50 feet high and 12-15 inches in trunk diameter; long,
slender branches form a rather open, rounded crown.

LEAVES.--Alternate, simple, 3-6 inches long and nearly as broad; broadly
obovate to oval; 5-9-lobed by deep, wide, rounded sinuses, the lobes
toothed and bristle-tipped; thin and firm; shining, bright green above,
paler beneath, both sides glabrous; turning brilliant scarlet in autumn;
petioles slender, 1-2 inches long.

FLOWERS.--May, with the leaves; monoecious; the staminate in glabrous
catkins 3-4 inches long; the pistillate on pubescent peduncles 1/2 inch
long, bright red, pubescent; calyx 4-5-lobed, reddish, pubescent;
corolla 0; stamens usually 4, with yellow anthers; stigmas long,
spreading, bright red.

FRUIT.--Autumn of second season; sessile or short-stalked acorns; cup
top-shaped to cup-shaped, with closely imbricated, slightly puberulous,
red-brown scales, inclosing about one-half of the nut; nut usually
short-ovoid, 1/2-3/4 inch long, light red-brown; kernel whitish, bitter.

WINTER-BUDS.--Terminal bud about 1/4 inch long, broadly ovoid, acute,
dark red-brown, pale-pubescent above the middle.

BARK.--Twigs at first scurfy-pubescent, later lustrous, green, finally
smooth, light brown; thick, dark gray or brown on old trunks, shallowly
fissured, scaly; inner bark red, not bitter.

WOOD.--Heavy, hard, strong, coarse-grained, light red-brown, with thick,
darker brown sapwood.

DISTRIBUTION.--Lower Peninsula, southern half.

HABITAT.--Prefers a light, dry, sandy soil.

NOTES.--Rapid of growth. Desirable for ornamental planting.


[Illustration: +Hill's Oak. Northern Pin Oak. Black Oak+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1.]


+FAGACEAE+

+Hill's Oak. Northern Pin Oak. Black Oak+

_Quercus ellipsoidalis E. J. Hill_


HABIT.--A tree 50-60 feet high, with a short trunk 2-3 feet in diameter;
forming a rather narrow, oblong crown of upright and horizontal
branches. Many small, drooping branches are sent out near the ground,
which eventually die; and it is to the stubs or pins which persist about
the trunk that the appelation Pin Oak is due.

LEAVES.--Alternate, simple, 3-7 inches long and about as broad; oval to
nearly orbicular; narrowly 5-7-lobed by deep, wide, rounded sinuses, the
lobes few-toothed, bristle-tipped; thin and firm; lustrous, bright green
above, paler beneath, both sides glabrous except for the tufts of hairs
in the axils of the veins beneath; petioles slender, glabrous.

FLOWERS.--May, with the leaves; monoecious; the staminate in puberulous
catkins 2-3 inches long; the pistillate red, tomentose, borne on stout,
tomentose, 1-3-flowered peduncles; calyx 2-5-lobed or-parted, glabrous
except at the apex, which is fringed with long, twisted hairs; corolla
0; stamens 2-5, with short filaments; stigmas 3, recurved, dark red.

FRUIT.--Autumn of second season; short-stalked or nearly sessile acorns;
cup top-shaped, with scales thin, puberulous, inclosing one-third to
one-half of the nut; nut ellipsoid, 1/2-3/4 inch long, light brown,
puberulous; kernel yellow, bitter.

WINTER-BUDS.--Terminal bud 1/8-1/4 inch long, ovoid, rather obtuse,
slightly angular, lustrous, red-brown.

BARK.--Twigs bright red-brown, covered with matted, pale hairs, becoming
glabrous, dark gray or brown; thin, dull gray to dark brown, rather
smooth or closely ribbed on the trunk; inner bark yellow.

WOOD.--Heavy, hard, strong, coarse-grained, red-brown, with thin, paler
sapwood.

DISTRIBUTION.--South-western part of the Lower Peninsula, but limits not
definitely known.

HABITAT.--Well-drained uplands, especially on clays; occasionally on the
borders of ponds and in low woods.

NOTES.--A new and comparatively little known species.


[Illustration: +Yellow Oak. Black Oak+

   1. Winter twig, × 1.
   2. Leaf, × 1/2.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1.]


+FAGACEAE+

+Yellow Oak. Black Oak+

_Quercus velutina Lam._


HABIT.--A medium-sized tree 50-60 feet high and 1-3 feet in trunk
diameter; slender branches and stout branchlets form a wide-spreading,
rounded crown.

LEAVES.--Alternate, simple, 5-10 inches long, 3-8 inches broad; ovate to
oblong; usually 7-lobed, some with shallow sinuses and broad, rounded,
mucronate lobes, others with wide, rounded sinuses extending half-way to
the midrib or farther and narrow-oblong or triangular, bristle-tipped
lobes, the lobes more or less coarse-toothed, each tooth bristle-tipped;
thick and leathery; dark green and shining above, pale and more or less
pubescent beneath; petioles stout, yellow, 3-6 inches long.

FLOWERS.--May, when the leaves are half grown; monoecious; the staminate
in pubescent catkins 4-6 inches long; the pistillate reddish, on short,
tomentose peduncles; calyx acutely 3-4-lobed, reddish, hairy; corolla 0;
stamens usually 4-5, with acute, yellow anthers; stigmas 3, divergent,
red.

FRUIT.--Autumn of second season; sessile or short-stalked acorns; cup
cup-shaped or turbinate, inclosing about one-half of the nut; scales
thin, light brown, hoary; nut ovoid, 1/2-3/4 inch long, red-brown, often
pubescent; kernel yellow, bitter.

WINTER-BUDS.--Terminal bud 1/4 inch long, ovoid to conical, obtuse,
strongly angled, hoary-tomentose.

BARK.--Twigs at first scurfy-pubescent, later glabrous, red-brown,
finally mottled gray; thick and nearly black on old trunks, deeply
furrowed and scaly; inner bark thick, yellow, very bitter.

WOOD.--Heavy, hard, strong, coarse-grained, bright red-brown, with thin,
paler sapwood.

DISTRIBUTION.--Southern half of the Lower Peninsula.

HABITAT.--Prefers glacial drift; dry or gravelly uplands; poor soils.

NOTES.--Rapid of growth. Undesirable for street use.


[Illustration: +Black Jack+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1.]


+FAGACEAE+

+Black Jack+

_Quercus marilandica Muench._


HABIT.--A small, shrubby tree 20-30 feet high, with a trunk diameter of
6-14 inches; spreading, often contorted branches form a rounded or
obovoid crown.

LEAVES.--Alternate, simple, 5-7 inches long and broad; broad-obovate;
more or less 3-lobed at the apex, the lobes entire or toothed,
bristle-tipped, very variable in size and shape; thick and leathery;
very lustrous and dark green above, yellowish and scurfy-pubescent
beneath; petioles short, stout.

FLOWERS.--May, with the leaves; monoecious; the staminate in slender,
hoary catkins 2-4 inches long; the pistillate rusty-tomentose, on short,
rusty-tomentose peduncles; calyx 4-5-lobed, thin, scarious, tinged with
red, pale-pubescent; corolla 0; stamens 4, with apiculate, red anthers;
stigmas recurved, dark red.

FRUIT.--Autumn of second season; short-stalked acorns; cup turbinate,
with large, red-brown, rusty-tomentose scales, inclosing about one-half
of the nut; nut subglobose, about 3/4 inch long, yellow-brown,
puberulous; kernel yellowish.

WINTER-BUDS.--Terminal bud 1/4 inch long, ovoid, acute, prominently
angled; scales light red-brown, rusty-hairy.

BARK.--Twigs at first light red and scurfy, later glabrous, red-brown,
and finally brown or ashy gray; thick and almost black on the trunk,
divided into nearly square plates.

WOOD.--Heavy, hard, strong, dark brown, with thick, lighter colored
sapwood.

DISTRIBUTION.--Southern Michigan (Ann Arbor and Lansing).

HABITAT.--Dry, sandy or clay barrens.

NOTES.--Rare in Michigan.


[Illustration: +Shingle Oak+

   1. Winter twig, × 2.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1.]


+FAGACEAE+

+Shingle Oak+

_Quercus imbricaria Michx._


HABIT.--A tree 40-50 feet high, with a trunk diameter of 1-2 feet;
forming a rather open, rounded crown of slender, horizontal branches.

LEAVES.--Alternate, simple, 4-6 inches long, 1-2 inches broad;
oblong-lanceolate to oblong-obovate; entire or somewhat undulate; thin,
very lustrous, dark green above, paler and pubescent beneath; petioles
stout, pubescent, 1/2 inch long.

FLOWERS.--May, with the leaves; monoecious; the staminate in slender,
hoary-tomentose catkins 2-3 inches long; the pistillate on slender,
tomentose peduncles; calyx 4-lobed, yellow, downy; corolla 0; stamens
4-5, with yellow anthers; stigmas short, recurved, greenish yellow.

FRUIT.--Autumn of second season; acorns on stout peduncles 1/2 inch long;
cup cup-shaped, with red-brown, downy scales, inclosing one-third to
one-half of the nut; nut subglobose, about 1/2 inch long, dark brown,
often striate; kernel very bitter.

WINTER-BUDS.--Terminal bud 1/8 inch long, ovoid, acute, lustrous, brown.

BARK.--Twigs lustrous, dark green, becoming brown; thick on old trunks,
light brown and slightly fissured.

WOOD.--Heavy, hard, coarse-grained, light red-brown, with thin, lighter
colored sapwood.

DISTRIBUTION.--Of rare occurrence in Michigan. Reported in Kalamazoo, St.
Joseph and Washtenaw Counties, Lower Peninsula.

HABITAT.--Rich uplands; fertile river-bottoms.

NOTES.--Desirable for ornamental uses. Hardy. Rapid of growth.


+SUMMER KEY TO THE SPECIES OF ULMUS+

   a. Leaves essentially smooth on both sides; branches often
   with corky, wing-like ridges; lowermost branches usually short
   and strongly drooping; main trunk usually continuous into the
   crown without dividing, giving to the tree a narrow-oblong
   outline. _U. racemosa_, p. 129.

   aa. Leaves usually rough on one or on both sides; branches
   without corky ridges; lowermost branches not short, not
   strongly drooping; main trunk usually dividing into several
   large limbs, giving to the tree a more or less vase-shaped
   outline.

   b. Leaves usually rough above, but smooth beneath, with
   petioles glabrous; bark of trunk gray, deeply fissured into
   broad, scaly ridges; inner bark not mucilaginous. _U.
   americana_, p. 127.

   bb. Leaves usually rough both sides, with petioles hairy; bark
   of trunk dark red-brown, shallowly fissured into large, loose
   plates; inner bark mucilaginous. _U. fulva_, p. 125.


+WINTER KEY TO THE SPECIES OF ULMUS+

  a. Buds conspicuously rusty-tomentose; twigs more or less
  pubescent; inner bark very mucilaginous when chewed. _U.
  fulva_, p. 125.

  aa. Buds not conspicuously rusty-tomentose; twigs glabrous;
  inner bark not mucilaginous.

  b. Bundle-scars usually 3; buds 1/8 inch long, glabrous; twigs
  without corky ridges; outline of tree vase-shaped. _U.
  americana_, p. 127.

  bb. Bundle-scars usually 4-6 in a curved line; buds 1/4 inch
  long, somewhat pilose; twigs often with corky ridges; outline
  of tree narrow-oblong. _U. racemosa_, p. 129.


[Illustration: +Slippery Elm. Red Elm+

   1. Winter twig, × 2.
   2. Leaf, × 1.
   3. Flowering branchlet, × 1.
   4. Perfect flower, enlarged.
   5. Fruit, × 1.]


+URTICACEAE+

+Slippery Elm. Red Elm+

_Ulmus fulva Michx._ [_Ulmus pubescens Walt._]


HABIT.--A medium-sized tree 40-60 feet high, with a short trunk 1-2 feet
in diameter; spreading branches form a broad, open, flat-topped crown.

LEAVES.--Alternate, simple, 4-7 inches long, about one-half as broad;
ovate-oblong; coarsely doubly serrate; thick and firm; dark green and
rough above, paler and somewhat rough beneath; petioles short, stout,
hairy.

FLOWERS.--March-April, before the leaves; mostly perfect; borne on short
pedicels in crowded fascicles; calyx campanulate, 5-9-lobed, green,
hairy; corolla 0; stamens 5-9, with dark red anthers; stigmas 2, reddish
purple.

FRUIT.--May; semi-orbicular, 1-seeded samaras, short-stalked in dense
clusters; seed cavity brown-tomentose; wings smooth, nearly 3/4 inch
long.

WINTER-BUDS.--Terminal bud absent; lateral buds ovoid, obtuse, dark
brown, rusty-tomentose, 1/4 inch long.

BARK.--Twigs at first bright green and pubescent, becoming light to dark
brown or grayish; thick on old trunks, dark red-brown, shallowly
fissured into large, loose plates; inner bark mucilaginous.

WOOD.--Heavy, hard, strong, very close-grained, durable, easy to split
while green, dark red-brown, with thin, lighter colored sapwood.

DISTRIBUTION.--Of frequent occurrence throughout the state.

HABITAT.--Prefers stream-banks and bottom-lands; rich, moist hillsides;
rocky ridges and slopes.

NOTES.--Grows more rapidly than _U. americana_.


[Illustration: +White Elm. American Elm. Water Elm+

   1. Winter twig, × 2.
   2. Leaf, × 1/2.
   3. Flowering branchlet, × 1/2.
   4. Flower, enlarged.
   5. Fruit, × 2.]


+URTICACEAE+

+White Elm. American Elm. Water Elm+

_Ulmus americana L._


HABIT.--A tree 75-100 feet high, with a trunk diameter of 2-6 feet;
commonly dividing 20-30 feet above the ground into a few large branches
which rise upward and outward to form a vase-shaped outline.

LEAVES.--Alternate, simple, 4-6 inches long, one-half as broad;
obovate-oblong to oval; coarsely doubly serrate; thick and firm; dark
green and rough above, pale and pubescent or glabrous beneath; petioles
short and stout.

FLOWERS.--March-April, before the leaves; mostly perfect; small, brown to
red; borne on slender pedicels in loose fascicles; calyx campanulate,
5-9-lobed; corolla 0; stamens 4-9, with bright red anthers; ovary
2-celled; styles 2, green.

FRUIT.--May; ovate, 1-seeded samaras, smooth both sides, hairy on the
margin, 1/2 inch long, long-stemmed in crowded clusters.

WINTER-BUDS.--Terminal bud absent; lateral buds ovoid, acute, flattened,
glabrous, brown, 1/8 inch long.

BARK.--Twigs at first light green and downy, becoming glabrous,
red-brown, finally ash-gray; on old trunks thick, ash-gray, deeply
fissured into broad, scaly ridges.

WOOD.--Heavy, hard, strong, tough, difficult to split, coarse-grained,
light brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Common throughout the state.

HABITAT.--Prefers deep, rich, moist loam; bottom-lands; stream-banks.

NOTES.--Grows rapidly. Long-lived. The roots run along near the surface
of the ground for a great distance. An ideal street tree.


[Illustration: +Cork Elm. Rock Elm+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1.
   4. Flowering branchlet, × 1.
   5. Flower, enlarged.
   6. Fruit, × 1.]


+URTICACEAE+

+Cork Elm. Rock Elm+

_Ulmus racemosa Thomas_ [_Ulmus Thomasi Sarg._]


HABIT.--A large tree sometimes reaching a height of 100 feet and a trunk
diameter of 5 feet, but usually somewhat smaller; strongly drooping
lateral and lower branches form a narrow, oblong crown.

LEAVES.--Alternate, simple, 3-6 inches long, one-half as broad; obovate
to oblong-oval, more or less dished; coarsely doubly serrate; thick and
firm; lustrous, dark green above, pale-pubescent beneath; petioles
pubescent, 1/4 inch long.

FLOWERS.--March-April, before the leaves; mostly perfect; greenish; borne
on slender, drooping pedicels in loose racemes; calyx campanulate,
7-8-lobed; corolla 0; stamens 7-8, with purple anthers; ovary hairy,
2-styled.

FRUIT.--May; ovate, 1-seeded samaras, pubescent all over, 1/2 inch long.

WINTER-BUDS.--Terminal bud absent; lateral buds ovoid, acute, brown,
pilose, 1/4 inch long.

BARK.--Twigs at first light brown and pubescent, becoming lustrous,
red-brown, finally gray-brown with corky, wing-like ridges; thick and
grayish on the trunk, with wide fissures separating broad, flat, scaly
ridges.

WOOD.--Heavy, very strong and tough, close-grained, light red-brown, with
thick, lighter colored sapwood.

DISTRIBUTION.--Frequent in the southern third of the Lower Peninsula.

HABITAT.--Dry, gravelly uplands; rocky ridges and slopes; heavy clay
soils; river-banks.

NOTES.--A good street tree, but less graceful in habit than _U.
americana_.


[Illustration: +Hackberry. Nettle-tree+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 3/4.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1.]


+URTICACEAE+

+Hackberry. Nettle-tree+

_Celtis occidentalis L._


HABIT.--A medium-sized tree, 40-60 feet high, with a short, straight
trunk 1-2 feet in diameter which branches a few feet from the ground
into a few large limbs and many slender, horizontal, zigzag branches,
forming a broad, rounded crown.

LEAVES.--Alternate, simple, 2-4 inches long and one-half as broad; ovate
to ovate-lanceolate, oblique at the base, usually long-pointed; coarsely
serrate above the entire base; thin; glabrous, light green above, paler
beneath, turning light yellow late in autumn; petioles short, slender,
hairy.

FLOWERS.--May, with or soon after the leaves; polygamo-monoecious;
greenish; inconspicuous; on slender pedicels; the staminate in clusters
at the base of the shoot, the pistillate usually solitary in the axils
of the upper leaves; calyx greenish, deeply 5-lobed; corolla 0; stamens
5; ovary 1-celled.

FRUIT.--September-October, remaining on the tree through the winter;
slender-stalked, fleshy, globular drupes, 1/4 inch long, dark purple;
edible.

WINTER-BUDS.--Terminal bud absent; lateral buds light brown, 1/4 inch
long, ovoid, acute, flattened, the tip appressed.

BARK.--Twigs greenish, puberulous, becoming lustrous, red-brown in their
first winter; on old trunks thick, light brown or silvery gray, broken
into deep, short ridges or warty excrescences.

WOOD.--Heavy, soft, coarse-grained, weak, light yellow, with thick,
whitish sapwood.

DISTRIBUTION.--Common throughout the Lower Peninsula.

HABITAT.--Prefers rich, moist, well-drained soil, but will grow on
gravelly or rocky hillsides. Common along river-banks.

NOTES.--Hardy throughout its range. Grows slowly and irregularly in
youth. Easily transplanted. Not desirable as a street tree, but appears
well in ornamental grounds. Very tolerant of shade.


[Illustration: +Osage Orange+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Staminate flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flowering branchlet, × 1/2.
   7. Pistillate flower, enlarged.
   8. Fruit, × 1/4.]


+URTICACEAE+

+Osage Orange+

_Maclura pomifera (Raf.) Schneider_ [_Toxylon pomiferum Raf._] [_Maclura
aurantiaca Nutt._]


HABIT.--A tree 20-30 feet high, with a short trunk 1-2 feet in diameter;
divides into a few large limbs with curving branches, forming a
symmetrical, rounded crown.

LEAVES.--Alternate, simple, 3-5 inches long, 2-3 inches broad; ovate to
oblong-lanceolate; entire; thick and firm; dark green and shining above,
paler beneath; petioles slender, pubescent, 1-1/2-2 inches long.

FLOWERS.--June, after the leaves; dioecious; the staminate
slender-pedicelled, borne in a dense raceme at the end of long, slender,
drooping peduncles; the pistillate in dense, globose heads at the end of
short, stout peduncles; calyx 4-lobed, hairy; corolla 0; stamens 4;
style covered with white, stigmatic hairs.

FRUIT.--Autumn; pale green, orange-like, 4-5 inches in diameter, composed
of numerous small drupes, crowded and grown together.

WINTER-BUDS.--Terminal bud absent; lateral buds depressed-globular,
partly hidden in the bark, pale brown.

BARK.--Twigs at first bright green, pubescent, becoming orange-brown and
armed with stout, straight, axillary spines; dark orange-brown on the
trunk and deeply furrowed.

WOOD.--Heavy, very hard and strong, flexible, coarse-grained, very
durable, bright orange, with thin, lemon colored sapwood.

NOTES.--A native of the South, but hardy throughout Michigan. A desirable
ornamental tree. Extensively planted for hedges.


[Illustration: +Red Mulberry+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1.
   4. Spike of staminate flowers, × 1.
   5. Staminate flower, enlarged.
   6. Spike of pistillate flowers, × 1.
   7. Pistillate flower, enlarged.
   8. Fruit, × 1.]


+URTICACEAE+

+Red Mulberry+

_Morus rubra L._


HABIT.--A small tree 20-30 feet high, with a short trunk 10-15 inches in
diameter; forming a dense, round-topped crown of stout, spreading
branches and more or less zigzag, slender branchlets.

LEAVES.--Alternate, simple, 3-5 inches long, nearly as broad; outline
variable, ovate to semi-orbicular, often 3-5-lobed; coarsely serrate;
thin; dark blue-green and smooth or rough above, pale and more or less
downy beneath; petioles 1-2 inches long, smooth, exuding a milky juice
when cut.

FLOWERS.--May, with the leaves; monoecious or dioecious; the staminate in
dense spikes 1-2 inches long, on short, hairy peduncles; the pistillate
in dense spikes about 1 inch long, on short, hairy peduncles; calyx
4-lobed, hairy; corolla 0; stamens 4, with green anthers; stigmas 2,
spreading.

FRUIT.--July; 1 inch long; consisting of drupes about 1/32 inch long,
each inclosed in a thickened, fleshy calyx; berry-like; bright red at
first, finally blackish; sweet, juicy, edible.

WINTER-BUDS.--Terminal bud absent; lateral buds ovoid, abruptly pointed,
1/4 inch long, lustrous, light brown.

BARK.--Twigs greenish and more or less downy, becoming smooth and
brownish; trunk dark brown tinged with red and more or less furrowed.

WOOD.--Light, soft, weak, rather tough, coarse-grained, very durable,
pale orange, with thick, lighter colored sapwood.

DISTRIBUTION.--Southern portion of the Lower Peninsula, as far north as
the Muskegon river.

HABITAT.--Prefers rich soil in river-bottoms.

NOTES.--Easily transplanted. Grows rapidly in good, moist soil.


[Illustration: +Tulip Poplar. Tulip-tree. White-wood+

   1. Winter twig, × 1.
   2. Leaf, × 1/2.
   3. Flowering branchlet, × 1/2.
   4. Fruit (opened and partly disseminated), × 1/2.]


+MAGNOLIACEAE+

+Tulip Poplar. Tulip-tree. White-wood+

_Liriodendron tulipifera L._


HABIT.--A large tree 70-100 feet high, with a columnar trunk 2-5 feet in
diameter; forming a rather open, conical crown of slender branches.

LEAVES.--Alternate, simple, 5-6 inches long and broad; 4-lobed; entire;
lustrous, dark green above, pale or glaucous beneath, turning clear
yellow in autumn; petioles slender, angled, 5-6 inches long.

FLOWERS.--May-June, after the leaves; perfect; terminal; solitary on
stout peduncles; tulip-shaped, greenish yellow, 1-1/2-2 inches long;
sepals 3, greenish, early deciduous; petals 6, in 2 rows, greenish
yellow with an orange spot at the base, early deciduous; stamens
numerous, somewhat shorter than the petals; pistils numerous, clinging
together about a central axis; ovary 1-celled.

FRUIT.--September-October; a narrow, light brown cone 2-1/2-3 inches
long, composed of numerous carpels; carpels long, flat, with a
1-2-seeded nutlet at the base, separating from the slender spindle at
maturity.

WINTER-BUDS.--Terminal bud 1/2-1 inch long, obtuse, flattish, dark red,
covered with a glaucous bloom.

BARK.--Twigs smooth, lustrous, reddish, becoming brownish, and at length
gray; ashy gray, thin and scaly on young trunks, becoming thick,
brownish, and deeply furrowed with age.

WOOD.--Light, soft, brittle, weak, easily worked, light yellow or brown,
with thin, cream-white sapwood.

DISTRIBUTION.--Lower Peninsula south of the Grand River. Formerly common,
but becoming rare.

HABITAT.--Prefers deep, rich, rather moist soil, but adapts itself
readily to any good, light soil.

NOTES.--Difficult to transplant, but rapid of growth when once
established. Not disfigured by insect enemies. Good for ornamental
planting.


[Illustration: +Sassafras+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaves, × 1/2.
   4. Staminate flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flowering branchlet, × 1/2.
   7. Pistillate flower, enlarged.
   8. Fruit, × 1/2.]


+LAURACEAE+

+Sassafras+

_Sassafras variifolium (Salisb.) Ktse._ [_Sassafras sassafras (L.)
Karst._] [_Sassafras officinale Nees & Eberm._]


HABIT.--Usually a large shrub, but often a small tree 20-40 feet high,
with a trunk diameter of 10-20 inches; stout, often contorted branches
and a bushy spray form a flat, rather open crown.

LEAVES.--Alternate, simple, 3-6 inches long, 2-4 inches broad; oval to
oblong or obovate; entire or 1-3-lobed with deep, broad sinuses and
finger-like lobes; thin; dull dark green above, paler beneath; petioles
slender, about 1 inch long.

FLOWERS.--May, with the leaves; dioecious; greenish yellow; on slender
pedicels, in loose, drooping, few-flowered racemes 2 inches long; calyx
deeply 6-lobed, yellow-green; corolla 0; stamens of staminate flower 9,
in 3 rows, of pistillate flower 6, in 1 row; ovary 1-celled.

FRUIT.--September-October; an oblong-globose, lustrous, dark blue berry,
3/8 inch long, surrounded at the base by the scarlet calyx, borne on
club-shaped, bright red pedicels.

WINTER-BUDS.--Terminal buds 1/3 inch long, ovoid, acute, greenish,
soft-pubescent, flower-bearing; lateral buds much smaller, sterile or
leaf-bearing. Aromatic.

BARK.--Twigs glabrous, lustrous, yellow-green, spicy-aromatic, becoming
red-brown and shallowly fissured when 2-3 years old; thick, dark
red-brown and deeply and irregularly fissured into firm, flat ridges on
old trunks.

WOOD.--Soft, weak, brittle, coarse-grained, very durable in the soil,
aromatic, dull orange-brown, with thin, light yellow sapwood.

DISTRIBUTION.--Southern portion of Lower Peninsula as far north as
Grayling.

HABITAT.--Prefers well-drained, stony or sandy soil; woods; abandoned
fields; peaty swamps.

NOTES.--Rapid of growth. Suckers freely. Difficult to transplant.
Propagated easily from seed.


[Illustration: +Sycamore. Button-wood. Buttonball-tree+

   1. Winter twig, × 1.
   2. Portion of twig, side view, × 1.
   3. Vertical section of twig, summer
   bud and leaf petiole, enlarged.
   4. Leaf, × 3/8.
   5. Flowering branchlet, × 1/2.
   6. Staminate flower, enlarged.
   7. Pistillate flower, enlarged.
   8. Fruit, × 3/8.
   9. Achene, enlarged.]


+PLATANACEAE+

+Sycamore. Button-wood. Buttonball-tree+

_Platanus occidentalis L._


HABIT.--A large tree 70-100 feet high, with a trunk diameter of 3-8 feet;
commonly dividing near the ground into several large secondary trunks,
forming a broad, open, irregular crown of massive, spreading branches.

LEAVES.--Alternate, simple, 5-10 inches long and broad; broadly ovate in
outline; more or less 3-5-lobed by broad, shallow sinuses, the lobes
sinuate-toothed; thin and firm; bright green above, paler beneath,
glabrous both sides; petioles stout, puberulous, 1-2 inches long.

FLOWERS.--May, with the leaves; monoecious; borne in dense heads; the
staminate dark red, on short, axillary peduncles; the pistillate
greenish, on long, slender, terminal peduncles; sepals 3-6, minute;
petals 3-6, minute; stamens 3-6, usually 4; styles long, incurved, red.

FRUIT.--October, persistent on the limbs through the winter; brown heads
about 1 inch in diameter, on slender, glabrous stems 3-6 inches long.

WINTER-BUDS.--Terminal bud absent; lateral buds 1/4-3/8 inch long,
conical, blunt, lustrous, pale brown; forming in summer within the
petiole of the leaf.

BARK.--Twigs pale green and tomentose, becoming smooth, dark green,
finally grayish; thick, red-brown on the trunk and broken into oblong,
plate-like scales, separating higher up into thin plates which peel off,
exposing the greenish or yellowish inner bark.

WOOD.--Heavy, tough, hard, rather weak, coarse-grained, difficult to
split, light red-brown, with thick, darker colored sapwood.

DISTRIBUTION.--Lower Peninsula as far north as Roscommon County.

HABITAT.--Prefers rich bottom-lands along the borders of rivers and
lakes.

NOTES.--Rapid of growth. Bears transplanting well. Often planted as a
shade tree. Fungous diseases disfigure it seriously.


+SUMMER KEY TO THE SPECIES OF PYRUS+

  a. Leaves simple; fruit a light green pome an inch or more in
  diameter; branches contorted, bearing many short, spur-like
  branchlets. _P. coronaria_, p. 145.

  aa. Leaves compound; fruit berry-like, 1/4 inch in diameter,
  bright red; branches not contorted, not bearing many short,
  spur-like branchlets. _P. americana_, p. 147.


+WINTER KEY TO THE SPECIES OF PYRUS+

  a. Bundle-scars 3 or in 3 compound, but distinct groups; buds
  1/8-1/4 inch long; branches contorted, bearing many short,
  spur-like branchlets; fruit a pome an inch or more in diameter,
  light green. _P. coronaria_, p. 145.

  aa. Bundle-scars 4-many in a single U-shaped line, not forming
  3 distinct groups; buds about 1/2 inch long; branches not
  contorted, not bearing many short, spur-like branchlets; fruit
  berry-like, 1/4 inch in diameter, bright red. _P. americana_,
  p. 147.


[Illustration: +Sweet Crab. American Crab+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 3/4.
   4. Flowering branchlet, × 1/2.
   5. Vertical section of flower
   with petals removed, × 1/2.
   6. Fruit, × 1/2.]


+ROSACEAE+

+Sweet Crab. American Crab+

_Pyrus coronaria L._ [_Malus coronaria Mill._]


HABIT.--Often a bushy shrub, but frequently a small tree 15-25 feet high,
with a trunk 8-12 inches in diameter; forming a broad, rounded crown of
rigid, contorted branches bearing many short, spur-like branchlets.

LEAVES.--Alternate, simple, 3-4 inches long, almost as broad; ovate to
nearly triangular; sharply and deeply serrate, sometimes lobed;
membranaceous; bright green above, paler beneath, glabrous both sides;
petioles long, slender, often with two dark glands near the middle.

FLOWERS.--May, after the leaves; perfect; 1-1/2-2 inches across; very
fragrant; borne on slender pedicels in 5-6-flowered umbels; calyx
urn-shaped, 5-lobed, tomentose; petals 5, rose colored to white; stamens
10-20; ovary hairy; styles 5.

FRUIT.--October; a depressed-globose pome, 1-1-1/2 inches in diameter,
pale green, very fragrant, with a waxy surface.

WINTER-BUDS.--Terminal bud 1/8-1/4 inch long, obtuse, bright red; lateral
buds smaller.

BARK.--Twigs at first hoary-tomentose, becoming glabrous, red-brown;
thin, red-brown, breaking into longitudinal fissures on the trunk.

WOOD.--Heavy, rather soft, close-grained, weak, red-brown, with thick,
yellow sapwood.

DISTRIBUTION.--Southern portion of the Lower Peninsula as far north as
Roscommon County.

HABITAT.--Rich, moist, but well-drained soil in thickets and along
streams.

NOTES.--An excellent ornamental tree or shrub for small gardens and
shrubberies. The fruit is sometimes gathered for making preserves.


[Illustration: +Mountain Ash+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/3.
   4. Vertical section of flower, enlarged.
   5. Portion of a fruiting cyme, × 1.]


+ROSACEAE+

+Mountain Ash+

_Pyrus americana (Marsh.) DC._ [_Sorbus americana Marsh._]


HABIT.--A small tree 15-20 feet high, with a trunk diameter of not over a
foot; branches slender, spreading, forming a narrow, rounded crown.

LEAVES.--Alternate, compound, 6-9 inches long. Leaflets 9-17, 2-3 inches
long and 1/2-3/4 inch broad; sessile or nearly so, except the terminal;
lanceolate to oblong-lanceolate, taper-pointed; finely and sharply
serrate above the entire base; membranaceous; glabrous, dark
yellow-green above, paler beneath, turning clear yellow in autumn.
Petioles slender, grooved, enlarged at the base.

FLOWERS.--May-June, after the leaves; perfect; 1/8 inch across; borne on
short, stout pedicels in many-flowered, flat cymes 3-5 inches across;
calyx urn-shaped, 5-lobed, puberulous; petals 5, white; stamens
numerous; styles 2-3.

FRUIT.--October, but persistent on the tree throughout the winter; a
berry-like pome, subglobose, 1/4 inch in diameter, bright red, with
thin, acid flesh; eaten by birds in the absence of other food.

WINTER-BUDS.--Terminal bud about 1/2 inch long, ovoid, acute, with curved
apex; lateral buds smaller, appressed; scales rounded on the back,
purplish red, more or less pilose above, gummy.

BARK.--Twigs at first red-brown and hairy, becoming glabrous, dark brown;
thin, light gray-brown on the trunk, smooth, or slightly roughened on
old trees; inner bark fragrant.

WOOD.--Light, soft, close-grained, weak, pale brown, with thick, lighter
colored sapwood.

DISTRIBUTION.--Ludington and northward, principally along the shore of L.
Michigan, but common throughout the Upper Peninsula.

HABITAT.--Prefers rich, moist soil on river-banks and on the borders of
cold swamps; rocky hillsides and mountains.

NOTES.--More often a shrub. Easily transplanted, but slow of growth. One
of the most beautiful trees of our northern forests.


[Illustration: +Serviceberry+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1.
   4. Flowering branchlet, × 1/2.
   5. Vertical section of flower, enlarged.
   6. Fruiting branchlet, × 1/2.]


+ROSACEAE+

+Serviceberry+

_Amelanchier canadensis (L.) Medic._


HABIT.--A small tree 25-40 feet in height, with a tall trunk 6-12 inches
in diameter; forming a narrow, rounded crown of many small limbs and
slender branchlets.

LEAVES.--Alternate, simple, 3-4 inches long and about one-half as broad;
ovate to obovate; finely and sharply serrate; glabrous, dark green
above, paler beneath; petioles slender, about 1 inch long.

FLOWERS.--April, when the leaves are about one-third grown; perfect;
large, white, borne in drooping racemes 3-5 inches long; calyx 5-cleft,
campanulate, villous on the inner surface; petals 5, strap-shaped,
white, about 1 inch in length; stamens numerous; styles 5, united below.

FRUIT.--June-August; globular, berry-like pome, 1/3-1/2 inch long;
turning from bright red to dark purple with slight bloom; sweet and
edible when ripe.

WINTER-BUDS.--Yellow-brown, narrow-ovoid to conical, sharp-pointed,
1/4-1/2 inch long; bud-scales apiculate, slightly pubescent.

BARK.--Twigs smooth, light green, becoming red-brown; thin, pale
red-brown on the trunk, smoothish or divided by shallow fissures into
narrow, longitudinal, scaly ridges.

WOOD.--Heavy, very hard, strong, close-grained, dark red-brown, with
thick, lighter colored sapwood.

DISTRIBUTION.--Common throughout the state.

HABITAT.--Prefers rich soil of dry, upland woods and hillsides.

NOTES.--Hardy throughout the state. Grows in all soils and situations
except in wet lands.


[Illustration: +Dotted Haw+

_Crataegus punctata Jacq._

   1. Winter twig, × 1.
   2. Leaf, × 1.
   3. Flowering branchlet, × 1/2.
   4. Vertical section of flower, enlarged.
   5. Fruit, × 1.]


+ROSACEAE+

+The Haws, Thorns, Hawthorns or Thorn-apples+

_Crataegus L._


Owing to the complexity of the various forms in this group, the present
state of uncertainty as to the value of certain characters, and the
questionable validity of many of the assigned names, it is thought to be
beyond the scope of this bulletin to give more than a general
description of the group as a whole, recommending the more ambitious
student to the various manuals and botanical journals and papers for
more detailed information.

The _Crataegi_ are generally low, wide-spreading trees or shrubs, with
strong, tortuous branches and more or less zigzag branchlets usually
armed with stiff, sharp thorns. The bark varies from dark red to gray
and is shallowly fissured or scaly. The leaves are alternate, simple,
generally serrate, often lobed, with short or long petioles. The flowers
appear in May or June, with or after the leaves, in simple or compound
corymbs, whitish or pinkish, perfect. The fruit is a red to yellow,
sometimes blue or black pome, subglobose to pear-shaped, with usually
dry and mealy flesh and 1-5 seeds. The winter-buds are small, nearly
globose, lustrous brown. _Crataegus_ produces wood which is heavy, hard,
tough, close-grained, red-brown, with thick, pale sapwood. The Haws are
trees of the pasture-lands, the roadside, the open woods and the
stream-banks, and are more common in the southern than in the northern
portions of the state. Some of the species are desirable as ornaments in
parks and gardens on account of their beautiful and abundant flowers and
showy fruits.


+SUMMER KEY TO THE SPECIES OF PRUNUS+

  a. Leaves oblong-ovate to obovate, abruptly acuminate at the
  apex; marginal teeth not incurved.

  b. Margin of leaves sharp-serrate with spreading teeth; leaves
  not rugose, the veins not prominent; fruit 1/4-1/2 inch long,
  bright red, racemose, July-August; bark of trunk brown, smooth
  or only slightly fissured; usually a large shrub. _P.
  virginiana_, p. 157.

  bb. Margin of leaves crenate-serrate; leaves more or less
  rugose, the veins prominent; fruit about 1 inch long
  orange-red, clustered, August-September; bark of trunk
  gray-brown, early splitting off in large, thick plates; a small
  tree. _P. nigra_, p. 161.

  aa. Leaves oval to oblong-lanceolate, taper-pointed at the
  apex; marginal teeth incurved.

  b. Fruit light red, clustered, July-August; twigs usually less
  than 1/16 inch thick; pith of twigs brown; tree northern. _P.
  pennsylvanica_, p. 139.

  bb. Fruit black, racemose, August-September; twigs usually more
  than 1/16 inch thick; pith of twigs white; tree southern. _P.
  serotina_, p. 155.


+WINTER KEY TO THE SPECIES OF PRUNUS+

  a. Terminal bud present; bark of young trunks rather smooth.

  b. Buds clustered at the tips of all shoots; twigs usually less
  than 1/16 inch thick; pith of twigs brown. _P. pennsylvanica_,
  p. 159.

  bb. Buds not clustered, or clustered only on short, spur-like
  branchlets; twigs usually more than 1/16 inch thick; pith of
  twigs white.

  c. Buds usually 1/4 inch or less in length; bud-scales uniform
  in color, apiculate at the apex; bark on old trunks blackish,
  rough-scaly; small to large tree. _P. serotina_, p. 155.

  cc. Buds usually 1/4-1/2 inch long; bud-scales grayish on the
  margins, rounded at the apex; bark on old trunks brown, smooth
  or only slightly fissured; usually a large shrub. _P.
  virginiana_, p. 157.

  aa. Terminal bud absent; bark of young trunks early splitting
  off in large, thick plates. _P. nigra_, p. 161.


[Illustration: +Black Cherry+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 3/4.
   4. Margin of leaf, enlarged.
   5. Flowering branchlet, × 1/2.
   6. Vertical section of flower, enlarged.
   7. Fruiting branchlet, × 1/2.]


+ROSACEAE+

+Black Cherry+

_Prunus serotina Ehrh._ [_Padus serotina (Ehrh.) Agardh._]


HABIT.--A medium-sized tree 40-50 feet high and 8-36 inches in trunk
diameter; branches few, large, tortuous, forming a rather spreading,
oblong or rounded crown.

LEAVES.--Alternate, simple, 2-5 inches long, about one-half as broad;
oval or oblong to oblong-lanceolate; finely serrate, with teeth
incurved; subcoriaceous; dark green and very lustrous above, paler
beneath, glabrous both sides; petioles short, slender, usually bearing 2
red glands near the blade.

FLOWERS.--May-June, when the leaves are half grown; perfect; 1/4 inch
across; borne on slender pedicels in many-flowered, loose racemes 4-5
inches long; calyx cup-shaped, 5-lobed; petals 5, white; stamens 15-20;
stigma thick, club-shaped.

FRUIT.--August-September; a globular drupe, 1/3-1/2 inch in diameter,
nearly black, with dark purple, juicy flesh; slightly bitter, edible.

WINTER-BUDS.--Terminal bud about 1/4 inch long, ovoid, blunt to acute;
scales keeled on the back, apiculate, light brown.

BARK.--Twigs and branches red to red-brown; young trunks dark red-brown,
smooth; blackish on old trunks and rough, broken into thick, irregular
plates; bitter, aromatic.

WOOD.--Light, rather hard, strong, close- and straight-grained, light
brown or red, with thin, yellow sapwood.

DISTRIBUTION.--Frequent in the southern half of the Lower Peninsula, rare
in the northern half and the Upper Peninsula.

HABITAT.--Prefers a rich, moist soil, but grows well on dry, gravelly or
sandy soils.

NOTES.--Grows very rapidly in youth.


[Illustration: +Choke Cherry+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1.
   4. Margin of leaf, enlarged.
   5. Flowering branchlet, × 1/2.
   6. Vertical section of flower, enlarged.
   7. Fruit, × 1/2.]


+ROSACEAE+

+Choke Cherry+

_Prunus virginiana L._ [_Padus virginiana (L.) Roemer_]


HABIT.--Usually a large shrub, but sometimes a small tree 15-25 feet
high, with a crooked, often leaning trunk 5-6 inches in diameter;
forming a spreading, somewhat rounded crown.

LEAVES.--Alternate, simple, 2-4 inches long, one-half as broad; obovate
to oblong-obovate or oval, abruptly acuminate at the apex; finely and
sharply serrate; dull dark green above, paler beneath, glabrous both
sides; petioles short, slender, glandular at the apex.

FLOWERS.--May, when the leaves are half grown; perfect; about 1/2 inch
across; borne on short, slender pedicels in many-flowered racemes 3-6
inches long; calyx cup-shaped, 5-lobed; petals 5, white; stamens 15-20;
stigma broad, on a short style.

FRUIT.--July-August; a globular drupe, 1/4-1/2 inch in diameter, usually
bright red, often yellow to almost black, with dark red flesh;
astringent, but edible.

WINTER-BUDS.--Terminal bud 1/4-1/2 inch long, conical, acute; scales
rounded at the apex, light brown, smooth.

BARK.--Twigs at first light brown or greenish, becoming red-brown,
finally dark brown; thin, dark brown on the trunk, slightly fissured.

WOOD.--Heavy, hard, close-grained, weak, light brown, with thick, lighter
colored sapwood.

DISTRIBUTION.--Common throughout the entire state.

HABITAT.--Prefers a deep, rich, moist loam, but is common on less
favorable sites.

NOTES.--The most widely distributed tree of North America, extending from
the arctic circle to Mexico, from the Rocky Mountains to the Atlantic
Ocean.


[Illustration: +Wild Red Cherry. Pin Cherry+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1.
   4. Margin of leaf, enlarged.
   5. Flowering branchlet, × 1/2.
   6. Flower, enlarged.
   7. Fruit, × 1.]


+ROSACEAE+

+Wild Red Cherry. Pin Cherry+

_Prunus pennsylvanica L. f._


HABIT.--A slender tree, seldom over 30 feet high, with a trunk diameter
of 8-10 inches; crown rather open, narrow, rounded, with slender,
regular branches.

LEAVES.--Alternate, simple, 3-5 inches long, 3/4-1-1/4 inches broad;
oblong-lanceolate; finely and sharply serrate; bright green and shining
above, paler beneath; petioles slender, 1/2-1 inch long, glandular near
the blade.

FLOWERS.--May-June, with the leaves; perfect; about 1/2 inch across,
borne on slender pedicels in 4-5-flowered umbels, generally clustered,
2-3 together; calyx 5-cleft, campanulate; petals 5, white, 1/4 inch
long; stamens 15-20.

FRUIT.--July-August; a globular drupe, 1/4 inch in diameter, light red,
with thick skin and sour flesh.

WINTER-BUDS.--Terminal bud 1/8 inch long, broadly ovoid, rather blunt,
brownish, smooth.

BARK.--Twigs at first lustrous, red, marked by orange colored lenticels,
becoming brownish; red-brown and thin on the trunk, peeling off
horizontally into broad, papery plates; bitter, aromatic.

WOOD.--Light, soft, close-grained, light brown, with thin, yellow
sapwood.

DISTRIBUTION.--Throughout the northern portion of the state, extending
southward to Ionia County.

HABITAT.--Abundant on sand-lands; roadsides; burned-over lands;
clearings; hillsides.

NOTES.--Rapid of growth. Short-lived.


[Illustration: +Canada Plum. Red Plum+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Flowering branchlet, × 1/2.
   5. Vertical section of flower, × 1.
   6. Fruiting branchlet, × 1/2.]


+ROSACEAE+

+Canada Plum. Red Plum+

_Prunus nigra Ait._ [_Prunus americana, v. nigra Waugh_]


HABIT.--A small tree 20-25 feet high and 5-8 inches in trunk diameter;
usually divides 5-6 feet from the ground into a number of stout, upright
branches, forming a narrow, rigid crown.

LEAVES.--Alternate, simple, 3-5 inches long and one-half as broad;
oblong-ovate to obovate, abruptly acuminate at the apex; doubly
crenate-serrate; thick and firm; glabrous, light green above, paler
beneath; petioles short, stout, bearing 2 large red glands near the
blade.

FLOWERS.--May, before the leaves; perfect; slightly fragrant; about 1
inch across; borne on slender, glabrous, red pedicels in 2-3-flowered
umbels; calyx 5-lobed, dark red; petals 5, white; stamens 15-20, with
purple anthers; ovary 1-celled; style 1; stigma 1.

FRUIT.--August-September; a fleshy drupe, about 1 inch long,
oblong-ovoid, with a tough, thick, orange-red skin nearly free from
bloom, and yellow flesh adherent to the flat stone. Eaten raw or cooked.

WINTER-BUDS.--Terminal bud absent; lateral buds 1/8-1/4 inch long, ovate,
acute, chestnut-brown.

BARK.--Twigs green, marked by numerous pale excrescences, later dark
brown; thin, gray-brown and smooth on young trunks, but soon splitting
off in large, thick plates, exposing the darker inner bark.

WOOD.--Heavy, hard, strong, close-grained, light red-brown, with thin,
lighter colored sapwood.

DISTRIBUTION.--Upper Peninsula and the Lower Peninsula north of Lansing.

HABITAT.--Prefers rich, alluvial soil along streams.

NOTES.--Suckers freely, forming low, broad thickets.


[Illustration: +Coffeetree. Kentucky Coffeetree+

   1. Winter twig, × 1.
   2. Leaf, × 1/4.
   3. Leaflet, × 1/2.
   4. Vertical section of staminate flower, enlarged.
   5. Vertical section of pistillate flower, enlarged.
   6. Fruit, × 1/4.]


+LEGUMINOSAE+

+Coffeetree. Kentucky Coffeetree+

_Gymnocladus dioica (L.) Koch_ [_Gymnocladus canadensis Lam._]


HABIT.--A slender tree 50-75 feet high, with a trunk diameter of 2-3
feet; divides near the ground into several stems which spread slightly
to form a narrow, pyramidal crown; branchlets stout, clumsy, blunt, with
conspicuous leaf-scars.

LEAVES.--Alternate, bipinnately compound, 1-3 feet long. Leaflets 40 or
more, 2-2-1/2 inches long and one-half as broad; short-stalked; ovate,
acute; entire; thin and firm; dark green above, pale yellow-green and
glabrous beneath. Petioles stout, terete, glabrous. Appear late in
spring.

FLOWERS.--June, after the leaves; dioecious; greenish white; the
staminate short-stalked, in racemose corymbs 3-4 inches long; the
pistillate long-stalked, in racemes 10-12 inches long; calyx tubular,
hairy; petals 5, keeled, nearly white; stamens 10; ovary hairy.

FRUIT.--Ripens in autumn, but remains closed until late in winter;
short-stalked, red-brown legumes 6-10 inches long, 1-1/2-2 inches wide,
containing 6-9 large, flat seeds.

WINTER-BUDS.--Terminal bud absent; lateral buds minute, depressed, 2 in
the axil of each leaf, bronze-brown, silky-pubescent.

BARK.--Twigs coated with short, dense, reddish pubescence, becoming light
brown; thick, deeply fissured and scaly on the trunk, dark gray.

WOOD.--Heavy, somewhat soft, strong, coarse-grained, very durable in
contact with the soil, light red-brown, with thin, lighter colored
sapwood.

DISTRIBUTION.--Southern Michigan as far north as the Grand River.
Infrequent.

HABITAT.--Prefers bottom-lands and rich soil.

NOTES.--The seeds in early days were used as a substitute for coffee.


[Illustration: +Honey Locust. Three-thorned Acacia+

   1. Winter twig, × 1.
   2. Vertical section through lateral buds, enlarged.
   3. Leaf, × 1/4.
   4. Leaflet, × 1.
   5. Staminate flowering branchlet, × 1/2.
   6. Staminate flower, enlarged.
   7. Pistillate flowering branchlet, × 1/2.
   8. Pistillate flower, enlarged.
   9. Fruit, × 1/3.
   10. Spine from trunk, × 1/2.]


+LEGUMINOSAE+

+Honey Locust. Three-thorned Acacia+

_Gleditsia triacanthos L._


HABIT.--A tree usually 50-75 feet high, with a trunk diameter of 2-3
feet; dividing near the ground into several large, upright branches
which divide again into long, slender, horizontal branchlets; both trunk
and large branches armed with stout, rigid, simple or branched spines.

LEAVES.--Alternate, pinnately or bipinnately compound, 7-12 inches long.
Leaflets 18 or more, 3/4-1-1/2 inches long, one-third as broad;
lanceolate-oblong; remotely crenulate-serrate; thin; lustrous, dark
green above, dull yellow-green beneath. Petioles and rachises pubescent.

FLOWERS.--May-June, when the leaves are nearly full grown;
polygamo-dioecious; the staminate in short, many-flowered, pubescent
racemes; the pistillate in slender, few-flowered racemes; on shoots of
the preceding season; calyx campanulate, hairy 3-5-lobed; petals 3-5,
greenish; stamens 3-10; ovary 1-celled, woolly.

FRUIT.--Autumn, falling in early winter; flat, pendent, twisted, brown
legumes, 12-18 inches long, short-stalked in short racemes; seeds 12-14,
oval, flattened.

WINTER-BUDS.--Terminal bud absent; lateral buds minute, 3 or more
superposed, glabrous, brownish.

BARK.--Twigs lustrous, red-brown, becoming gray-brown; thick on the
trunk, iron-gray to blackish and deeply fissured into long, narrow
ridges roughened by small scales.

WOOD.--Hard, strong, coarse-grained, durable in contact with the ground,
red-brown, with thin, pale sapwood.

DISTRIBUTION.--Indigenous to the extreme southern portion of the state,
but is planted as far north as Bay City.

HABITAT.--Prefers deep, rich loam, but grows on a variety of soils.

NOTES.--Grows rapidly and is long-lived and free from disease. Easily
transplanted. The leaves appear late in spring and fall early in autumn.
The stiff spines and long pods which litter the ground make the tree
unsuitable for street or ornamental use.


[Illustration: +Redbud. Judas-tree+

   1. Winter twig, × 1.
   2. Portion of twig, front view, enlarged.
   3. Portion of twig, side view, enlarged.
   4. Leaf, × 1/2.
   5. Flowering branchlet, × 1.
   6. Vertical section of flower, enlarged.
   7. Fruit, × 1/2.]


+LEGUMINOSAE+

+Redbud. Judas-tree+

_Cercis canadensis L._


HABIT.--A small tree 20-30 feet high, with a trunk diameter of 10-15
inches; divided near the ground into stout, straggling branches to form
a broad, flat crown.

LEAVES.--Alternate, simple, 3-5 inches long and broad; heart-shaped or
rounded; entire; thick; glabrous, dark green above, paler beneath,
turning bright yellow in autumn; petioles slender, terete, enlarged at
the base.

FLOWERS.--April-May, before or with the leaves; perfect; 1/2 inch long;
borne on short, jointed pedicels in fascicles of 4-8; calyx campanulate,
5-toothed, dark red; petals 5, rose color; stamens 10, in 2 rows.

FRUIT.--June-July, remaining on the tree until early winter; a
short-stalked legume 2-1/2-3 inches long, pointed at both ends, rose
color; seeds 10-12, brownish, 1/4 inch long.

WINTER-BUDS.--Terminal bud absent; lateral buds 1/8 inch long, obtuse,
somewhat flattened and appressed, brownish.

BARK.--Twigs lustrous, brown, becoming dark or grayish brown; red-brown,
deeply fissured, with a scaly surface on old trunks.

WOOD.--Heavy, hard, coarse-grained, weak, dark red-brown, with thin,
lighter colored sapwood.

DISTRIBUTION.--Valleys of the Grand and Raisin Rivers and southward.

HABITAT.--Prefers the borders of streams and rich bottom-lands, often in
the shade of other trees.

NOTES.--A rapid grower. Hardy within its range. Can be transplanted with
success only when very young. Plants begin to produce flowers freely
when 4-5 years old. Much used in landscape gardening.


[Illustration: +Locust. Black Locust+

   1. Winter twig, × 1.
   2. Vertical section through lateral buds, enlarged.
   3. Leaf, × 1/2.
   4. Raceme of flowers, × 1/2.
   5. Flower, with part of corolla removed, enlarged.
   6. Fruit, × 1/2.]


+LEGUMINOSAE+

+Locust. Black Locust+

_Robinia pseudo-acacia L._


HABIT.--A tree 50-75 feet high, with a trunk diameter of 2-3 feet;
forming a narrow, oblong crown of irregular, more or less contorted
branches.

LEAVES.--Alternate, compound, 8-14 inches long. Leaflets 7-21,
short-petiolate, 1-2 inches long, about one-half as broad; ovate to
oblong-oval; entire; very thin; dull dark green above, paler beneath,
glabrous both sides. Petioles slender, pubescent.

FLOWERS.--May-June, after the leaves; perfect; showy and abundant; very
fragrant; borne on slender pedicels in loose, drooping racemes 4-5
inches long; about 1 inch long; calyx short, bell-shaped, 5-lobed,
hairy; corolla papilionaceous, white, 5-petaled; stamens 10.

FRUIT.--Late autumn, but persistent on the tree through the winter; a
smooth, dark brown, flat pod 3-4 inches long, containing 4-8 small,
flattish, brown seeds.

WINTER-BUDS.--Terminal bud absent; lateral buds minute, 3-4 superposed,
partially sunken within the leaf-scar, rusty-hairy.

BARK.--Twigs smooth, green, more or less rough-dotted at first, becoming
red-brown and armed with prickles; dark red-brown and thick on old
trunks, deeply furrowed into firm, sinuous ridges.

WOOD.--Heavy, very strong and hard, close-grained, very durable in
contact with the soil, brown, with very thin, pale yellow sapwood.

NOTES.--Native to the Appalachian Mountains, but much planted in Michigan
for ornamental and economic uses. Very rapid of growth in youth.
Short-lived. Seriously attacked by borers. Spreads by underground
shoots.


[Illustration: +Ailanthus. Tree of Heaven+

   1. Winter twig, × 1.
   2. Leaf, × 1/8.
   3. Leaflet, × 1/2.
   4. Staminate inflorescence, × 1/4.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1.]


+SIMARUBACEAE+

+Ailanthus. Tree of Heaven+

_Ailanthus glandulosa Desf._


HABIT.--A handsome, rapid-growing, short-lived tree, attaining a height
of 50-70 feet and a trunk diameter of 2-4 feet, with a spreading, rather
loose and open crown and a coarse, blunt spray.

LEAVES.--Alternate, pinnately compound, 1-3 feet long. Leaflets 11-41 in
number, 2-6 inches long and about one-third as broad; ovate-lanceolate;
entire with the exception of two or more coarse, glandular teeth at the
base; glabrous, dark green above, paler beneath, turning a clear yellow
in autumn or falling without change; ill-scented. Petioles smooth,
terete, swollen at the base.

FLOWERS.--June, when the leaves are full grown; polygamo-dioecious;
small, yellow-green, borne in upright panicles 6-12 inches or more in
length; calyx 5-lobed; petals 5, greenish, hairy; stamens 10. Staminate
flowers ill-scented, pistillate almost free from odor.

FRUIT.--October; 1-celled, 1-seeded samaras, spirally twisted, reddish or
yellow-green, borne in crowded clusters.

WINTER-BUDS.--Terminal bud absent; lateral buds about 1/8 inch long,
subglobose, brownish, downy.

BARK.--Twigs yellowish to red-brown, velvety-downy; thin, grayish and
shallowly fissured on old trunks.

WOOD.--Soft, weak, of coarse and open grain, pale yellow, satiny, with
thick, lighter colored sapwood.

NOTES.--A native of China, but naturalized in the United States and
planted frequently in southern Michigan as a foliage tree. Only the
pistillate trees should be planted, as these are almost free from the
objectionable odor of the staminate trees. The smoke and dust of our
large cities have little effect on the foliage, and the trees are
perfectly hardy in the southern part of the state.


+SUMMER KEY TO THE SPECIES OF ACER+

  a. Leaves simple; twigs usually without whitish bloom.

  b. Leaf-sinuses acute at the base.

  c. Leaf-lobes long and narrow, the sides of the terminal lobe
  diverging; leaves silvery white beneath; twigs rank-smelling
  when broken. _A. saccharinum_, p. 185.

  cc. Leaf-lobes short and broad, the sides of the terminal lobe
  converging; leaves not conspicuously white beneath; twigs not
  rank-smelling when broken.

  d. Leaves 2-4 inches broad, thin, not pentagonally 5-lobed;
  wings of fruit 3/4-1 inch long.

  e. Leaves distinctly white-downy beneath; twigs
  appressed-hairy, at least near the tip; fruit hanging in
  pendulous racemes, persistent on the tree until autumn; seed
  portion with pit-like depression on one side; usually a shrub
  or bushy tree. _A. spicatum_, p. 179.

  ee. Leaves not distinctly white-downy beneath; twigs glabrous;
  fruit hanging in clusters, falling in early summer; seed
  portion without pit-like depression on one side; medium-sized
  tree. _A. rubrum_, p. 187.

  dd. Leaves 4-7 inches broad, thick, pentagonally 5-lobed; wings
  of fruit 1-1/2 inches long. _A. pseudo-platanus_, p. 191.

  bb. Leaf-sinuses rounded at the base.

  c. Lower sides of leaves and petioles distinctly downy, the
  lobes undulate or entire; leaves very thick, drooping at the
  sides. _A. saccharum nigrum_, p. 183.

  cc. Lower sides of leaves and petioles essentially glabrous,
  the lobes serrate; leaves not thick, not drooping at the sides.

  d. Leaves coarsely and sparsely toothed or notched; bark not
  longitudinally white-striped; large trees.

  e. Twigs coarse; petioles exuding a milky juice when cut; wings
  of fruit diverging by nearly 180°; bark of the trunk closely
  fissured, not scaly. _A. platanoides_, p. 189.

  ee. Twigs slender; petioles not exuding a milky juice when cut;
  wings of fruit diverging only slightly; bark of the trunk
  deeply furrowed, often cleaving in long, thick plates. _A.
  saccharum_, p. 181.

  dd. Leaves finely and abundantly toothed; bark longitudinally
  white-striped; a bushy tree or shrub.

  aa. Leaves compound; twigs usually with whitish bloom. _A.
  negundo_, p. 193.


+WINTER KEY TO THE SPECIES OF ACER+

  a. Terminal buds usually under 1/4 inch in length.

  b. Buds white-woolly; twigs usually with a whitish bloom;
  opposite leaf-scars meeting; fruit often persistent on the tree
  until spring. _A. negundo_, p. 193.

  bb. Buds not white-woolly; twigs without whitish bloom;
  opposite leaf-scars not meeting; fruit not persistent on the
  tree in winter.

  c. Buds reddish or greenish; twigs bright red.

  d. Twigs strictly glabrous; buds glabrous; spherical flower
  buds clustered on the sides of the shoot; pith pink; large
  trees.

  e. Twigs rank-smelling when broken; tip of outer bud-scales
  often apiculate; tips of branches curving upwards; bark
  separating into long, thin flakes loose at the ends. _A.
  saccharinum_, p. 185.

  ee. Twigs not rank-smelling when broken; tip of outer
  bud-scales rounded; tips of branches not conspicuously curving
  upwards; bark rough-ridged, but seldom forming loose flakes.
  _A. rubrum_, p. 187.

  dd. Twigs appressed-hairy, at least near the tip; buds somewhat
  tomentose; spherical flower buds absent; pith brown; shrub or
  bushy tree. _A. spicatum_, p. 179.

  cc. Buds brownish; twigs brownish or grayish.

  d. Buds glabrous, or somewhat pubescent at the apex only; bark
  dark gray on the trunk. _A. saccharum_, p. 181.

  dd. Buds hoary-pubescent; bark sometimes almost black on the
  trunk. _A. saccharum nigrum_, p. 183.

  aa. Terminal buds usually 1/4-1/2 inch in length.

  b. Buds reddish; opposite leaf-scars meeting.

  c. Buds conspicuously stalked; bud-scales visible, 1 pair; bark
  longitudinally white-striped; small tree or large shrub. _A.
  pennsylvanicum_, p. 177.

  cc. Buds not conspicuously stalked; bud-scales visible, 2-3
  pairs; bark not white-striped; large tree. _A. platanoides_, p.
  189.

  bb. Buds bright green; opposite leaf-scars not meeting. _A.
  pseudo-platanus_, p. 191.


[Illustration: +Striped Maple. Moosewood. Whistlewood+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Staminate flowering branchlet, × 1/2.
   5. Vertical section of staminate flower, enlarged.
   6. Pistillate flowering branchlet, × 1/2.
   7. Vertical section of pistillate flower, enlarged.
   8. Fruit, × 3/4.]


+ACERACEAE+

+Striped Maple. Moosewood. Whistlewood+

_Acer pennsylvanicum L._


HABIT.--A small tree at best, more often a large shrub, seldom attaining
a height of more than 30 feet, with a short trunk 5-8 inches through.
The striped, upright branches form a rather compact crown.

LEAVES.--Opposite, simple, 5-6 inches long and nearly as broad; 3-lobed
above the middle with short, tapering lobes; palmately 3-nerved; sharply
doubly serrate; rounded or heart-shaped at the base; glabrous,
yellow-green above, paler beneath, turning pale yellow in autumn;
petioles stout, grooved.

FLOWERS.--May-June, when the leaves are nearly full grown; usually
monoecious; large, bright yellow, bell-shaped, in slender, drooping
racemes 4-6 inches long; calyx 5-parted; petals 5; stamens 7-8; ovary
downy.

FRUIT.--Ripens in autumn; glabrous, paired samaras in long, drooping,
racemose clusters, the wings 3/4 inch long, widely divergent, and marked
on one side of each nutlet by a small cavity.

WINTER-BUDS.--Bright red; terminal bud nearly 1/2 inch long,
short-stalked, with bud-scales keeled; lateral buds smaller, appressed.

BARK.--Twigs light green, mottled with black, smooth; trunk and branches
red-brown, marked longitudinally by broad, pale stripes.

WOOD.--Light, soft, close-grained, pinkish brown, with thick, lighter
colored sapwood.

DISTRIBUTION.--Abundant in the Upper Peninsula, extending southward as
far as Roscommon County in the Lower Peninsula.

HABITAT.--Cool, rocky or sandy woods, usually in the shade of other
trees.

NOTES.--In the Northwoods the green shoots are browsed by deer and moose.
Valued mostly for its aesthetic qualities. Of little or no economic
value.


[Illustration: +Mountain Maple+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1.]


+ACERACEAE+

+Mountain Maple+

_Acer spicatum Lam._

HABIT.--A bushy tree sometimes 25-30 feet high, with a short trunk 6-8
inches in diameter; small, upright branches form a small, rounded crown.
More often a straggling shrub.

LEAVES.--Opposite, simple, 4-5 inches long and two-thirds as broad;
3-lobed above the middle, the lobes coarsely crenate-serrate with
pointed teeth, the sinuses usually wide-angled and acute at the base;
thin; glabrous, dark green above, covered with a whitish down beneath,
turning scarlet and orange in autumn; veining prominent; petioles long,
slender, with enlarged base.

FLOWERS.--June, after the leaves are full grown; polygamo-monoecious;
small, yellow-green; in erect, slightly compound, many-flowered,
long-stemmed, terminal racemes; calyx downy, 5-lobed; petals 5; stamens
7-8; ovary tomentose.

FRUIT.--July; bright red, turning brown in late autumn; small, glabrous,
paired samaras, in pendulous, racemose clusters.

WINTER-BUDS.--Small, flattish, acute, bright red, more or less tomentose;
the terminal 1/8 inch long, containing the flowers.

BARK.--Twigs reddish, slightly hairy; very thin, red-brown, smooth or
slightly furrowed on the trunk.

WOOD.--Light, soft, close-grained, light brown, with thick, lighter
colored sapwood.

DISTRIBUTION.--Common in the Upper Peninsula; extends as far south as
Saginaw Bay.

HABITAT.--Damp forests; rocky woods; along streams; always in the shade
of other trees.

NOTES.--Forms much of the undergrowth of our northern forests. Little
used, except for fire-wood.


[Illustration: +Sugar Maple. Hard Maple. Rock Maple+

   1. Winter twig, × 2.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Staminate flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flowering branchlet, × 1/2.
   7. Pistillate flower, enlarged.
   8. Fruit, × 1.]


+ACERACEAE+

+Sugar Maple. Hard Maple. Rock Maple+

_Acer saccharum Marsh._ [_Acer saccharinum Wang._]


HABIT.--A stately tree 60-100 feet in height, with a trunk diameter of
3-4 feet; in the open forming stout, upright branches near the ground,
in forests making remarkably clean trunks to a good height; the crown is
a broad, round-topped dome.

LEAVES.--Opposite, simple, 3-5 inches long and broad; usually 5-lobed
(sometimes 3-lobed), the lobes sparingly wavy-toothed, the sinuses broad
and rounded at the base; thin and firm; opaque, dark green above,
lighter and glabrous beneath, turning yellow and red in autumn; petioles
long, slender.

FLOWERS.--May, with the leaves; polygamo-monoecious or dioecious; on
thread-like, hairy pedicels in nearly sessile corymbs; greenish yellow;
calyx campanulate, 5-lobed; corolla 0; stamens 7-8; ovary hairy.

FRUIT.--September-October, germinating the following spring; paired
samaras, glabrous, with wings about 1 inch long, diverging slightly.

WINTER-BUDS.--Small, acute, red-brown, glabrous or somewhat pubescent
toward the apex, the terminal 1/4 inch long, the lateral smaller,
appressed.

BARK.--Twigs smooth, pale brown, becoming gray and smooth on the
branches; old trunks dark gray, deeply furrowed, often cleaving up at
one edge in long, thick plates.

WOOD.--Heavy, hard, strong, close-grained, tough, durable, light brown,
with thin, lighter colored sapwood.

DISTRIBUTION.--Found throughout the entire state.

HABITAT.--Prefers moist, rich soil in valleys and uplands and moist,
rocky slopes.

NOTES.--The most important hardwood in Michigan. The tree which produces
the bulk of the maple sugar of the market.


[Illustration: +Black Maple. Black Sugar Maple+

   1. Winter twig, × 2.
   2. Leaf, × 1/2.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flower, enlarged.
   6. Fruit, × 1.]


+ACERACEAE+

+Black Maple. Black Sugar Maple+

_Acer saccharum nigrum (Michx. f.) Britt._ [_Acer nigrum Michx._]


HABIT.--A stately tree, sometimes reaching a height of 80 feet, with a
trunk diameter of 2-3 feet; branches stout, forming a broad, rounded,
symmetrical crown.

LEAVES.--Opposite, simple, concave, 5-7 inches across, the breadth
usually exceeding the length; usually 5-lobed at maturity, the two lower
lobes being small, often reduced to a mere curve in the outline, the
pointed lobes undulate or entire and narrowed from the broad, shallow
sinuses; thick and firm; glabrous above, downy beneath; petioles stout,
usually pendent, tomentose. The sides of the larger leaves often droop
giving to the tree an air of depression.

FLOWERS.--May, with the leaves; monoecious; in nearly sessile, umbel-like
corymbs; about 1/4 inch long, yellow, on slender, hairy pedicels 2-3
inches long; calyx campanulate, pilose, 5-lobed; corolla 0; stamens 7-8;
ovary hairy.

FRUIT.--Ripens in autumn; glabrous, paired samaras, clustered on drooping
pedicels; wings set wide apart, but only slightly diverging.

WINTER-BUDS.--Small, ovoid, acute, with dark red-brown, acute scales,
hoary-pubescent on the outer surface.

BARK.--Twigs smooth, pale gray; becoming thick, deeply furrowed and
sometimes almost black on the trunk.

WOOD.--Hard, heavy, strong, close-grained, creamy white, with thin,
lighter colored sapwood.

DISTRIBUTION.--Lower Peninsula, south-eastern portion.

HABITAT.--Prefers low, moist, rich soil of river-bottoms, but does well
on gravelly soils and uplands.

NOTES.--Very variable. A very good shade tree because of its dense
foliage. It is claimed by some that the finest grades of maple sugar are
made from the sap of this tree.


[Illustration: +Silver Maple. Soft Maple+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1/2.
   4. Staminate flowering branchlet, × 1.
   5. Staminate flower, enlarged.
   6. Pistillate flowering branchlet, × 1.
   7. Pistillate flower, enlarged.
   8. Fruit, × 1/2.]


+ACERACEAE+

+Silver Maple. Soft Maple+

_Acer saccharinum L._ [_Acer dasycarpum Ehrh._]


HABIT.--A beautiful tree, growing to a height of 60-80 feet, with a trunk
diameter of 2-4 feet, usually separating near the ground into 3-4
upright stems which are destitute of branches for a considerable
distance. Usually the long, slender branches bend downwards, but with
their tips ascending in a graceful curve. Crown broad, especially in its
upper portion.

LEAVES.--Opposite, simple, 3-6 inches long and nearly as broad; usually
5-lobed by narrow, acute sinuses which extend nearly to the midrib, the
lobes often sublobed, sharply toothed; light green above, silvery white
beneath, turning pale yellow in autumn; petioles long, slender,
drooping.

FLOWERS.--March-April, before the leaves; polygamo-monoecious or
dioecious; small, yellow-green, in crowded, sessile umbels; calyx
5-lobed (sometimes each lobe again divided); corolla 0; stamens 3-7;
ovary hairy.

FRUIT.--May, germinating as soon as it reaches the ground; paired
samaras, large, glabrous, curving inwards, one samara often aborted.

WINTER-BUDS.--Dark red, blunt; the terminal about 1/4 inch long, with
bud-scales often apiculate at the apex; flower-buds clustered on side
spurs.

BARK.--Twigs smooth, red-gray, lustrous; young trunks gray, smooth; old
trunks dark gray, more or less furrowed, separating into thin, loose
scales.

WOOD.--Hard, strong, close-grained, rather brittle, perishable, pale
brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Lower Peninsula south of Saginaw Bay.

HABITAT.--Prefers low, rich bottom-lands, subject to occasional
inundation, but not in swamps.

NOTES.--A rapid grower, adapting itself to a variety of soils. Does not
do well on dry, elevated ground. The first tree to blossom in early
spring.

[Illustration: +Red Maple. Soft Maple+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 1.
   4. Fascicle of staminate flowers, × 1.
   5. Staminate flower, enlarged.
   6. Fascicle of pistillate flowers, × 1.
   7. Pistillate flower, enlarged.
   8. Fruit, × 3/4.]


+ACERACEAE+

+Red Maple. Soft Maple+

_Acer rubrum L._


HABIT.--A medium-sized tree 40-50 feet high, occasionally in swamps 60-75
feet; trunk 1-3 feet in diameter; upright branches, which form a low,
rather narrow, rounded crown.

LEAVES.--Opposite, simple, 3-4 inches long and nearly as broad; 3-5-lobed
by broad, acute sinuses, the lobes irregularly doubly serrate or
toothed; glabrous, green above, whitish and generally glabrous beneath,
turning bright scarlet in autumn; petioles long, slender.

FLOWERS.--March-April, before the leaves; polygamo-monoecious or
dioecious; in few-flowered fascicles on shoots of the previous year, the
pistillate red, the staminate orange; sepals 4-5; petals 4-5; stamens
5-8; ovary smooth.

FRUIT.--May-June, germinating immediately after reaching the ground;
samaras small, on drooping pedicels 2-4 inches long; wings about 1 inch
long, diverging at about a right angle.

WINTER-BUDS.--Dark red, blunt; terminal bud about 1/8 inch long, with
bud-scales rounded at the apex; flower-buds clustered on side spurs.

BARK.--Twigs bright red, lustrous, becoming smooth and light gray on the
branches; old trunks dark gray, ridged, separating into plate-like
scales.

WOOD.--Heavy, close-grained, not strong, light brown, with thick, lighter
colored sapwood.

DISTRIBUTION.--Throughout the entire state.

HABITAT.--Prefers swamp-lands or banks of streams; rarely found on
hillsides.

NOTES.--A valuable shade and ornamental tree. Sugar has been made in
small quantities from the sap.


[Illustration: +Norway Maple+

   1. Winter twig, × 1.
   2. Leaf, × 1/2.
   3. Raceme of staminate flowers, × 1/2.
   4. Staminate flower, enlarged.
   5. Raceme of pistillate flowers, × 1/2.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1/2.]


+ACERACEAE+

+Norway Maple+

_Acer platanoides L._


HABIT.--A tall, handsome tree, with a height of 40-60 feet, and a trunk
diameter of 1-2 feet, having a round, spreading crown of stout branches,
resembling _A. saccharum_. Twigs coarse.

LEAVES.--Opposite, simple, 5-7 inches broad, and almost as long; thin;
5-7-lobed at maturity, lobes remotely coarse-toothed with the teeth
drawn out into filamentous points, separated by rounded, scallop-like
sinuses; glabrous, bright green both sides, turning pale yellow in
autumn; petioles long, slender, exuding a milky juice when cut.

FLOWERS.--May-June, before or with the leaves; dioecious; large,
yellow-green, in erect, short, flat racemes; sepals 5; petals 5; stamens
8.

FRUIT.--Ripens in autumn and germinates the following spring; pendent on
long stalks; large, glabrous, paired samaras, with wings 2 inches long,
diverging by nearly 180°.

WINTER-BUDS.--Yellow-green, red or dull red-brown; terminal bud about 1/4
inch long, broad, short-stalked, with bud-scales strongly keeled;
lateral buds small, appressed; buds exuding a milky juice when cut.

BARK.--Twigs lustrous, light brown to greenish; trunk dark gray, becoming
closely fissured, not scaly.

WOOD.--Moderately heavy, hard, close-grained, whitish or brownish, with
white sapwood.

NOTES.--Exotic from Europe. Extensively planted in cities for its
abundant shade. The roots strike deep and spread laterally, enabling the
tree to hold its own in a city environment. It holds its leaves two
weeks longer in autumn than do our native maples. A rapid grower.


[Illustration: +Sycamore Maple+

   1. Winter twig, × 1.
   2. Leaf, × 1/2.
   3. Flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Perfect flower, enlarged.
   6. Fruit, × 1/2.]


+ACERACEAE+

+Sycamore Maple+

_Acer pseudo-platanus L._


HABIT.--A thrifty tree 50-60 feet high, with a trunk diameter of 2-3
feet; the crown roundish, spreading.

LEAVES.--Opposite, simple, 4-7 inches across, and as long as broad;
thick; pentagonally 5-lobed, the lobes more or less ovate, separated by
very narrow, acute sinuses extending about half-way to the midrib, the
lobes coarsely and irregularly blunt-serrate, crenate-serrate, or
slightly lobed; upper surface dark green and shining, somewhat wrinkled,
but paler dull green and glaucous beneath; petioles long, stout.

FLOWERS.--April, before the leaves; polygamo-monoecious; large, greenish
yellow, in pendent racemes of umbellate cymes of about three each;
sepals 5; petals 5; stamens 8, hairy; ovary hairy.

FRUIT.--Ripens in autumn and germinates the following spring; pendent on
long stalks; large, glabrous, paired samaras, with wings 1-1/2 inches
long, diverging at about a right angle.

WINTER-BUDS.--Bright green; terminal bud 1/4-1/2 inch long, ovoid to
subglobose, blunt, with bud-scales more or less keeled; lateral buds
small, divergent.

BARK.--Twigs lustrous, brown or gray, becoming slate colored on the
branches; trunk gray or brownish, smooth or flaking off in short scales.

WOOD.--Moderately heavy, hard, compact, brownish, with white sapwood.

NOTES.--Exotic from Europe. Much planted in our cities, where it is
thrifty, but short-lived. The crown is rather too broad for planting
anywhere except on our widest streets. The leaves last two weeks longer
in autumn than do those of our native maples.


[Illustration: +Boxelder. Ash-leaved Maple+

   1. Winter twig, × 1.
   2. Leaf, × 1/2.
   3. Staminate flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flowering branchlet, × 1/2.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1.]


+ACERACEAE+

+Boxelder. Ash-leaved Maple+

_Acer negundo L._ [_Negundo aceroides Muench._]


HABIT.--A sturdy little tree 30-50 feet high, with a trunk diameter of
1-2 feet. Trunk often divides near the ground into several stout,
wide-spreading branches, forming a broad, unsymmetrical, open crown.

LEAVES.--Opposite, pinnately compound. Leaflets 3-5 in number, 2-4 inches
long, 1-1/2-2-1/2 inches broad; ovate or oval; nearly entire,
irregularly and remotely coarse-toothed above the middle, or sometimes
3-lobed (often giving the leaflet a jagged outline); apex acute, base
variable; glabrous or somewhat pubescent at maturity, with prominent
veins. Petioles slender, 2-3 inches long, the enlarged base leaving
prominent crescent-shaped scars partly surrounding the winter-buds.

FLOWERS.--April, before or with the leaves; dioecious; small,
yellow-green; the staminate in clusters on long, thread-like, hairy
pedicels; the pistillate in narrow, drooping racemes; calyx hairy,
5-lobed; corolla 0; stamens 4-6; ovary pubescent.

FRUIT.--Early summer, but hanging until late autumn or early spring;
narrow, flat, winged samaras, in pairs, clustered in drooping, racemose
clusters.

WINTER-BUDS.--Terminal bud 1/8-1/4 inch long, acute, inclosed in two dull
red scales, often hoary or minutely pubescent; lateral buds obtuse,
appressed.

BARK.--Twigs greenish to purple, glaucous; trunk pale gray or light
brown, deeply cleft into broad ridges.

WOOD.--Light, soft, close-grained, weak, creamy white, with thick, hardly
distinguishable sapwood.

DISTRIBUTION.--Lower Peninsula as far north as Saginaw Bay.

HABITAT.--Banks of streams and borders of swamps. Prefers deep, moist
soil.

NOTES.--Accommodates itself to almost any situation. Easily transplanted.
Much planted for shade and ornament. Fast-growing, but short-lived.

+SUMMER KEY TO THE SPECIES OF AESCULUS+

   a. Leaflets usually 5; foliage ill-smelling when bruised; bark
   broken into thick plates; prickly bur about 1 inch in
   diameter. _A. glabra_, p. 199.

   aa. Leaflets usually 7; foliage not ill-smelling when bruised;
   bark broken into thin plates; prickly bur about 2 inches in
   diameter. _A. hippocastanum_, p. 197.


+WINTER KEY TO THE SPECIES OF AESCULUS+

   a. Terminal bud about 2/3 inch long; bud-scales covered with a
   glaucous bloom, not conspicuously resinous; bark broken into
   thick plates; prickly bur about 1 inch in diameter. _A.
   glabra_, p. 199.

   aa. Terminal bud 1-1-1/2 inches long; bud-scales conspicuously
   sticky-resinous, glistening; bark broken into thin plates;
   prickly bur about 2 inches in diameter. _A. hippocastanum_, p.
   197.


[Illustration: +Horse-chestnut+

   1. Winter twig, × 3/4.
   2. Leaf, × 1/6.
   3. Leaflet, × 1/2.
   4. Flower, × 1.
   5. Fruit, × 1/2.]


+SAPINDACEAE+

+Horse-chestnut+

_Aesculus hippocastanum L._


HABIT.--A handsome tree, with a height of 40-60 feet and a trunk diameter
of 1-2 feet, forming a broad, conical crown. The regularly occurring
branches ascend from the trunk at first, gradually bend downwards as
they lengthen, and end in a thick, upturning spray.

LEAVES.--Opposite, digitately compound. Leaflets usually 7, rarely 5, 5-7
inches long, 1-1/2-2-1/2 inches broad; obovate, wedge-shaped at the
base; irregularly and bluntly serrate; thick; rough, dark green above,
paler beneath, turning a rusty yellow in autumn. Petioles long, grooved,
swollen at the base.

FLOWERS.--May-June, after the leaves; polygamo-monoecious; large,
whitish, in showy, upright, terminal thyrses 8-12 inches long; pedicels
jointed, 4-6-flowered; calyx campanulate, 5-lobed; petals 5, white,
spotted with yellow and red, clawed; stamens 7, thread-like, longer than
the petals.

FRUIT.--October; a leathery, globular capsule about 2 inches in diameter,
roughened with short spines; containing 1-3 large, smooth, lustrous,
brown nuts, marked by large, pale scars.

WINTER-BUDS.--Terminal buds 1-1-1/2 inches long, acute, brownish, covered
with glistening, resinous gum; inner scales yellowish, becoming 1-1/2-2
inches long in spring, remaining until the leaves are nearly half grown.

BARK.--Twigs smooth, red-brown; trunk dark brown and broken into thin
plates by shallow fissures; rich in tannin, bitter.

WOOD.--Light, soft, close-grained, weak, whitish, with thin, light brown
sapwood.

NOTES.--A native of Greece, extensively cultivated throughout Europe and
America, where it is a favorite shade tree. A double-flowered variety,
_Aesculus hippocastanum, v. flòre plèno_, which bears no fruit is a
common garden form.


[Illustration: +Ohio Buckeye+

   1. Winter twig, × 1.
   2. Leaf, × 1/6.
   3. Leaflet, × 1/2.
   4. Flower, × 2.
   5. Fruit, × 1/2.
   6. Nut, × 1/2.]


+SAPINDACEAE+

+Ohio Buckeye+

_Aesculus glabra Willd._


HABIT.--A medium-sized tree 30-50 feet in height, with a trunk not over 2
feet in diameter; usually much smaller; slender, spreading branches,
forming a broad, rounded crown; twigs thick.

LEAVES.--Opposite, digitately compound. Leaflets usually 5, rarely 7, 3-6
inches long, 1-1/2-2-1/2 inches broad; ovate or oval, gradually narrowed
to the entire base; irregularly and finely serrate; glabrous,
yellow-green above, paler beneath, turning yellow in autumn. Petioles
4-6 inches long, slender, enlarged at the base. Foliage ill-smelling
when bruised.

FLOWERS.--April-May, after the leaves; polygamo-monoecious; small,
yellow-green, in terminal panicles 5-6 inches long and 2-3 inches broad,
more or less downy; pedicels 4-6-flowered; calyx campanulate, 5-lobed;
petals 4, pale yellow, hairy, clawed; stamens 7, with long, hairy
filaments.

FRUIT.--October; a thick, leathery, prickly capsule, about 1 inch in
diameter, containing a single large, smooth, lustrous, brown nut. A
large pale scar gives the name "Buckeye".

WINTER-BUDS.--Terminal buds 2/3 inch long, acute, resinous, brownish;
inner scales yellow-green, becoming 1-1/2-2 inches long in spring and
remaining until the leaves are nearly half grown.

BARK.--Twigs smooth, red-brown, becoming ashy gray; old trunks densely
furrowed and broken into thick plates; ill-smelling when bruised.

WOOD.--Light, soft, close-grained, weak, whitish, with thin, light brown
sapwood.

NOTES.--A native of the Mississippi River Valley. Occasionally planted in
southern Michigan for ornamental purposes, but is less popular than the
Horse-chestnut.


[Illustration: +Basswood+

   1. Winter twig, × 1.
   2. Leaf, × 1/2.
   3. Cyme of flowers, with its bract, × 1/2.
   4. Flower, with two petals, petaloid scales
   and stamens removed, enlarged.
   5. Stamen, enlarged.
   6. Fruit, × 1/2.]


+TILIACEAE+

+Basswood+

_Tilia americana L._


HABIT.--A tree usually 60-70 feet high, with a tall, straight trunk 2-4
feet in diameter; numerous slender branches form a dense, ovoid or
rounded crown.

LEAVES.--Alternate, simple, 5-6 inches long, 3-4 inches broad; obliquely
heart-shaped; coarsely serrate; thick and firm; glabrous, dull dark
green above, paler beneath; petioles slender, 1-2 inches long.

FLOWERS.--June-July, after the leaves; perfect, regular; yellowish white,
downy, fragrant; borne on slender pedicels in loose, drooping cymes, the
peduncle attached for half its length to a narrow, oblong, yellowish
bract; sepals 5, downy; petals 5, creamy white; stamens numerous, in 5
clusters; ovary 5-celled; stigma 5-lobed.

FRUIT.--October; globose, nut-like, woody, gray, tomentose, about the
size of peas.

WINTER-BUDS.--Terminal bud absent; lateral buds ovoid, acute, often
lopsided, smooth, dark red, 1/4 inch long.

BARK.--Twigs smooth, reddish gray, becoming dark gray or brown; dark gray
and smooth on young stems, on old trunks thick, deeply furrowed into
broad, scaly ridges.

WOOD.--Light, soft, close-grained, tough, light red-brown, with thick
sapwood of nearly the same color.

DISTRIBUTION.--Common in most parts of the Lower Peninsula, frequent in
the Upper Peninsula.

HABITAT.--Prefers rich, well-drained, loamy soils.

NOTES.--Rapid in growth. Easily transplanted. Recommended for street and
ornamental planting.


+SUMMER KEY TO THE SPECIES OF CORNUS+

   a. Leaves mostly alternate; branches usually greenish; flowers
   not surrounded by large petal-like bracts; fruit globular,
   blue, borne many in loose clusters. _C. alternifolia_, p. 207.

   aa. Leaves opposite; branches usually reddish or yellowish;
   flowers surrounded by large petal-like bracts; fruit ovoid,
   scarlet, borne in close clusters of 3-4. _C. florida_, p. 205.


+WINTER KEY TO THE SPECIES OF CORNUS+

   a. Leaf-scars mostly alternate; buds light brown; branches
   usually greenish. _C. alternifolia_, p. 207.

   aa. Leaf-scars opposite; buds greenish; branches usually
   reddish or yellowish. _C. florida_, p. 205.


[Illustration: +Flowering Dogwood. Dogwood. Boxwood+

   1. Winter twig, with leaf buds, × 1.
   2. Portion of twig, enlarged.
   3. Winter twig, with flower bud, × 1.
   4. Leaf, × 1/2.
   5. Flowering branchlet, × 1/2.
   6. Flower, enlarged.
   7. Fruit, × 1.]


+CORNACEAE+

+Flowering Dogwood. Dogwood. Boxwood+

_Cornus florida L._


HABIT.--A bushy tree with a height of 15-30 feet and a short trunk 8-12
inches in diameter; slender, spreading branches form a flat-topped
crown.

LEAVES.--Opposite, closely clustered at the ends of the branchlets,
simple, 3-5 inches long, 2-3 inches broad; ovate to elliptical;
obscurely wavy-toothed; thick and firm; bright green, covered with
minute, appressed hairs above, pale and more or less pubescent beneath,
turning bright scarlet in autumn; petioles short, grooved.

FLOWERS.--May, with the leaves; perfect; greenish; in dense clusters,
surrounded by 4 large, white or pinkish, petal-like bracts (often
mistaken for the corolla), borne on short, stout peduncles; calyx
4-lobed, light green; petals 4, yellow-green; stamens 4, alternate with
the petals; ovary 2-celled.

FRUIT.--October; an ovoid, scarlet drupe, borne in close clusters of 3-4;
flesh is bitter.

WINTER-BUDS.--Leaf-buds narrow-conical, acute, greenish; flower-buds
spherical or vertically flattened, grayish.

BARK.--Twigs pale green, becoming red or yellow-green their first winter,
later becoming light brown or red-gray; red-brown or blackish on the
trunk, often separating into quadrangular, plate-like scales.

WOOD.--Heavy, hard, strong, tough, close-grained, brownish, with thick,
lighter colored sapwood.

DISTRIBUTION.--Southern Michigan as far north as the Grand-Saginaw
Valley.

HABITAT.--Prefers rich, well-drained soil, usually under the shade of
other trees.

NOTES.--A valuable species for ornamental purposes. Rather slow of
growth.


[Illustration: +Blue Dogwood. Alternate-leaved Dogwood+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 3/4.
   4. Flowering branchlet, × 1/2.
   5. Flower, enlarged.
   6. Fruiting branchlet, × 1/2.]


+CORNACEAE+

+Blue Dogwood. Alternate-leaved Dogwood+

_Cornus alternifolia L. f._


HABIT.--A small tree or large shrub reaching a height of 25-30 feet and a
trunk diameter of 6-8 inches; more often smaller than this. The long,
slender branches are arranged in irregular whorls, forming flat,
horizontal tiers, giving the tree a storied effect.

LEAVES.--Mostly alternate and clustered at the ends of the branchlets;
simple, 3-5 inches long, 2-1/2-3 inches broad; oval or ovate,
long-pointed, wedge-shaped at the base; obscurely wavy-toothed; thin;
dark green, nearly glabrous above, paler and covered with appressed
hairs beneath, turning yellow and scarlet in autumn; petioles slender,
grooved, hairy, with clasping bases.

FLOWERS.--May-June, after the leaves; perfect; borne on slender pedicels
in many-flowered, irregular, open cymes from the season's shoots; calyx
cup-shaped, obscurely 4-toothed, covered with fine, silky, white hairs;
petals 4, cream colored; stamens 4; ovary 2-celled.

FRUIT.--October; a globular, blue-black drupe, borne in loose,
red-stemmed clusters; flesh bitter.

WINTER-BUDS.--Leaf-buds small, acute, light brown; flower-buds spherical
or vertically flattened.

BARK.--Twigs greenish or reddish, becoming smooth, dark green; thin, dark
red-brown and shallowly fissured on the trunk.

WOOD.--Heavy, hard, close-grained, red-brown, with thick, lighter colored
sapwood.

DISTRIBUTION.--Scattered throughout both peninsulas.

HABITAT.--Prefers moist, well-drained soil on the borders of streams and
swamps, often in the shade of other trees.

NOTES.--Hardy throughout the state. Easily transplanted. The only
_Cornus_ with alternate leaves and branches.


[Illustration: +Black Gum. Pepperidge+

   1. Winter twig, × 1.
   2. Portion of twig, enlarged.
   3. Leaf, × 3/4.
   4. Staminate flowering branchlet, × 1/2.
   5. Staminate flower, enlarged.
   6. Pistillate flowering branchlet, × 1/2.
   7. Pistillate flower, enlarged.
   8. Fruit, × 1/2.]


+CORNACEAE+

+Black Gum. Pepperidge+

_Nyssa sylvatica Marsh._ [_Nyssa multiflora Wang._]


HABIT.--A medium-sized tree 40-50 feet high, with a trunk diameter of 1-2
feet, forming a rounded to cylindrical crown of slender, spreading,
pendulous branches and a stiff, flat spray.

LEAVES.--Alternate, simple, 2-5 inches long, one-half as broad;
oblong-obovate to oval; entire, or sometimes wavy-margined; thick and
firm; very lustrous and dark green above, pale and often hairy beneath,
turning bright scarlet, on the upper surface only, in autumn; petioles
short.

FLOWERS.--May-June, with the leaves; polygamo-dioecious; greenish; borne
on slender, downy peduncles; the staminate slender-pedicelled, in
many-flowered heads; the pistillate sessile, in several-flowered
clusters; calyx cup-shaped, 5-toothed; petals 5; stamens 5-10; stigma
stout, terete, recurved.

FRUIT.--October; fleshy drupes, ovoid, blue-black, about 1/2 inch long,
sour, in clusters of 1-3.

WINTER-BUDS.--1/8-1/4 inch long, ovoid, obtuse, dark red.

BARK.--Twigs greenish or light brown, smooth or often downy, becoming
smooth, dark red-brown; thick, red-brown on old trunks, deeply furrowed.

WOOD.--Heavy, soft, strong, very tough, difficult to split, not durable
in contact with the soil, pale yellow, with thick, whitish sapwood.

DISTRIBUTION.--Frequent in the southern half of the Lower Peninsula. Has
been reported as far north as Manistee.

HABITAT.--Prefers the borders of swamps and low, wet lands. Rarely
flourishes in exposed situations.

NOTES.--Of great ornamental value. Not easily transplanted. Pith of twigs
with thin, transverse partitions.

+SUMMER KEY TO THE SPECIES OF FRAXINUS+

   a. Lateral leaflets sessile. _F. nigra_, p. 221.

   aa. Lateral leaflets petioluled.

   b. Twigs, petioles and lower sides of leaves pubescent. _F.
   pennsylvanica_, p. 215.

   bb. Twigs, petioles and lower sides of leaves essentially
   glabrous.

   c. Twigs prominently 4-angled. _F. quadrangulata_, p. 219.

   cc. Twigs terete.

   d. Lower sides of leaves essentially of the same color as the
   upper; leaflet-margins rather finely sharp-serrate. _F.
   pennsylvanica lanceolata_, p. 217.

   dd. Lower sides of leaves paler than the upper;
   leaflet-margins entire or obscurely serrate. _F. americana_,
   p. 213.


WINTER KEY TO THE SPECIES OF FRAXINUS

   a. Twigs prominently 4-angled; fruit falling in early autumn.
   _F. quadrangulata_, p. 219.

   aa. Twigs terete; fruit often persistent on the tree until
   mid-winter or the following spring.

   b. Buds rusty-tomentose; twigs more or less downy. _F.
   pennsylvanica_, p. 215.

   bb. Buds not tomentose; twigs not downy.

   c. Terminal bud black or nearly so, showing 3 pairs of scales
   in cross-section; bud-scales apiculate at the apex; samaras
   with broad wings, the seed portion flattish; bark flaky,
   rubbing off on the hand. _F. nigra_, p. 221.

   cc. Terminal bud brownish, showing 4 pairs of scales in
   cross-section; bud-scales rounded at the apex; samaras with
   narrow wings, the seed portion terete; bark ridged, not flaky
   and rubbing off on the hand.

   d. Upper margin of leaf-scars deeply concave. _F. americana_,
   p. 213.

   dd. Upper margin of leaf-scars not concave, but straight
   across or projecting upward. _F. pennsylvanica lanceolata_, p.
   217.


[Illustration: +White Ash+

   1. Winter twig, × 1.
   2. Leaf, × 1/4.
   3. Staminate flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flowering branchlet, × 1/2.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1.]


+OLEACEAE+

+White Ash+

_Fraxinus americana L._


HABIT.--A large tree 50-75 feet high, with a trunk diameter of 2-3 feet;
forming an open, pyramidal crown of long, slender, lateral branches and
a stout, rather sparse spray.

LEAVES.--Opposite, pinnately compound, 8-12 inches long. Leaflets usually
7-9, 3-5 inches long, 1-2 inches broad; short-stalked; ovate to
oblong-lanceolate; entire or obscurely serrate; thick and firm;
glabrous, dark green above, paler beneath. Petioles glabrous, stout,
grooved.

FLOWERS.--May, before the leaves; dioecious; borne in loose panicles on
shoots of the previous season; calyx campanulate, 4-lobed; corolla 0;
stamens 2, rarely 3; ovary 2-celled.

FRUIT.--August-September, persistent on the branches until mid-winter or
the following spring; samaras 1-2 inches long, in crowded, drooping,
paniculate clusters 6-8 inches long.

WINTER-BUDS.--Short, rather obtuse; bud-scales apiculate, keeled, 4
pairs, rusty-brown.

BARK.--Twigs at first dark green, becoming gray or light brown, often
covered with a glaucous bloom; gray, deeply furrowed into firm, narrow,
flattened ridges on the trunk.

WOOD.--Heavy, hard, strong, close-grained, tough, brown, with thick,
lighter colored sapwood.

DISTRIBUTION.--Of common occurrence throughout the state.

HABITAT.--Prefers a rich, moist, loamy soil, but grows in any
well-drained situation; common along stream-beds.

NOTES.--Grows rapidly. Easily transplanted. Fairly free from disease.
Leaves appear late in spring.


[Illustration: +Red Ash+

   1. Winter twig, × 1.
   2. Leaf, × 1/3.
   3. Staminate flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flowering branchlet, × 1/2.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1.]


+OLEACEAE+

+Red Ash+

_Fraxinus pennsylvanica Marsh._ [_Fraxinus pubescens Lam._]


HABIT.--A medium-sized tree 30-50 feet high, with a trunk diameter of 1-2
feet; stout, upright branches and slender branchlets form a compact,
broad, irregular crown.

LEAVES.--Opposite, pinnately compound, 10-12 inches long. Leaflets 7-9,
3-5 inches long, 1-1-1/2 inches broad; short-stalked; oblong-lanceolate
to ovate; slightly serrate or entire; thin and firm; glabrous,
yellow-green above, pale and silky-downy beneath. Petioles stout,
pubescent.

FLOWERS.--May, with the leaves; dioecious; borne in compact, downy
panicles on shoots of the previous season; calyx cup-shaped, 4-toothed;
corolla 0; stamens 2, rarely 3; ovary 2-celled.

FRUIT.--Early autumn, persistent on the branches throughout the winter;
samaras 1-2 inches long, in open, paniculate clusters.

WINTER-BUDS.--Small, rounded; bud-scales rounded on the back, 3 pairs,
rusty-brown, tomentose.

BARK.--Twigs pale-pubescent at first, lasting 2-3 years or often
disappearing during the first summer, finally ashy gray or brownish and
often covered with a glaucous bloom; brown or dark gray on the trunk,
with many longitudinal, shallow furrows; somewhat scaly.

WOOD.--Heavy, hard, strong, brittle, coarse-grained, light brown, with
thick, yellow-streaked sapwood.

DISTRIBUTION.--Not a common tree. Most frequent in the southern half of
the Lower Peninsula, but has been reported further north, i.e.,
Drummond's Island and Keweenaw County, Upper Peninsula.

HABITAT.--Prefers wet or moist, rich loam; river-banks; swampy lowlands.

NOTES.--A rapid grower in youth. Fairly immune from insect and fungous
diseases.


[Illustration: +Green Ash+

   1. Winter twig, × 1.
   2. Leaf, × 1/3.
   3. Staminate flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flowering branchlet, × 1/2.
   6. Pistillate flower, enlarged.
   7. Fruit, × 1.]


+OLEACEAE+

+Green Ash+

_Fraxinus pennsylvanica lanceolata (Borkh.) Sarg._ [_Fraxinus lanceolata
Borkh._] [_Fraxinus viridis Michx. f._]


Considered by some authors to be a distinct species, and by others a
variety of _F. pennsylvanica Marsh._, which it resembles. The main
points of difference are:

   The usual absence of pubescence from the branchlets,
   the underside of the leaflets, and the petioles.

   The rather narrower, shorter, and more sharply
   serrate leaflets.

   The color of the leaves, which is bright green on both
   sides.

A very hardy tree, of rapid growth and desirable habit, making it useful
for ornamental and street planting. Easily transplanted.

Of rare occurrence in Michigan, but has been reported from several
localities.


[Illustration: +Blue Ash+

   1. Winter twig, × 1.
   2. Leaf, × 1/2.
   3. Flowering branchlet, × 1.
   4. Flower, enlarged.
   5. Fruit, × 1/2.]


+OLEACEAE+

+Blue Ash+

_Fraxinus quadrangulata Michx._


HABIT.--A large tree 50-80 feet high, with a trunk diameter of 1-3 feet;
small, spreading branches and stout, 4-angled, more or less 4-winged
branchlets form a narrow crown.

LEAVES.--Opposite, pinnately compound, 8-12 inches long. Leaflets 5-9,
usually 7, 3-5 inches long, 1-2 inches broad; short-stalked;
ovate-oblong to lanceolate, long-pointed; coarsely serrate; thick and
firm; yellow-green above, paler beneath, glabrous. Petioles slender,
glabrous.

FLOWERS.--April, before the leaves; perfect; borne in loose panicles on
shoots of the previous season; calyx reduced to a ring; corolla 0;
stamens 2; ovary 2-celled.

FRUIT.--September-October, falling soon after; samaras 1-2 inches long,
in long, loose, paniculate clusters.

WINTER-BUDS.--Short, rather obtuse; bud-scales rounded on the back, 3
pairs, dark red-brown, somewhat pubescent.

BARK.--Twigs orange, rusty-pubescent, becoming brownish or grayish; on
the trunk light gray tinged with red, irregularly divided into large,
plate-like scales, often with the shaggy appearance of a Shagbark
Hickory.

WOOD.--Heavy, hard, close-grained, brittle, light yellow-streaked with
brown, with thick, light yellow sapwood.

DISTRIBUTION.--Occasionally in the southern half of the Lower Peninsula.
Nowhere abundant.

HABITAT.--Prefers rich, limestone hills, but grows well in fertile
bottom-lands.

NOTES.--Hardy and grows rapidly. A blue dye is made by macerating the
inner bark in water.


[Illustration: +Black Ash+

   1. Winter twig, × 1.
   2. Leaf, × 1/3.
   3. Staminate flowering branchlet, × 1/2.
   4. Staminate flower, enlarged.
   5. Pistillate flowering branchlet, × 1/2.
   6. Pistillate flowers, enlarged.
   7. Fruit, × 1.]


+OLEACEAE+

+Black Ash+

_Fraxinus nigra Marsh._ [_Fraxinus sambucifolia Lam._]


HABIT.--A tall tree 60-80 feet high, with a trunk diameter of 1-2 feet;
slender, upright branches form in the forest a narrow crown, in the open
a rounded, ovoid crown.

LEAVES.--Opposite, pinnately compound, 12-16 inches long. Leaflets 7-11,
3-5 inches long, 1-2 inches broad; sessile, except the terminal; oblong
to oblong-lanceolate, long-pointed; remotely, but sharply serrate; thin
and firm; dark green above, paler beneath, glabrous. Petioles stout,
grooved, glabrous.

FLOWERS.--May, before the leaves; polygamo-dioecious; borne in loose
panicles on shoots of the preceeding season; calyx 0; corolla 0; stamens
2; ovary 2-celled.

FRUIT.--August-September, falling early, or sometimes hanging on the tree
until the following spring; samaras 1-1-1/2 inches long, in open,
paniculate clusters 8-10 inches long.

WINTER-BUDS.--Ovoid, pointed; bud-scales rounded on the back, 3 pairs,
almost black.

BARK.--Twigs at first dark green, becoming ashy gray or orange, finally
dark gray and warted; thin, soft ash-gray and scaly on the trunk. Bark
flakes off on rubbing with the hand.

WOOD.--Heavy, tough, coarse-grained, weak, rather soft, dark brown, with
thin, lighter colored sapwood.

DISTRIBUTION.--Common throughout most portions of Michigan.

HABITAT.--Prefers deep, cold swamps and low river-banks, but grows in any
good soil.

NOTES.--Hardy throughout the state. Not easily transplanted. Foliage
falls early in autumn.

+SUMMER KEY TO THE SPECIES OF CATALPA+

   a. Leaves 5-8 inches long, thick; flowers 1-1/2 inches across,
   prominently yellow-spotted; seeds with _pointed_, fringed
   wings at each end; branches rather crooked and straggling;
   bark thin, separating into thin scales on the trunk. _C.
   bignonioides_, p. 227.

   aa. Leaves 8-12 inches long, thin; flowers 2-1/2 inches
   across, not prominently spotted; seeds with _rounded_,
   wide-fringed wings at each end; branches not crooked and
   straggling; bark thick, separating into thick scales on the
   trunk. _C. speciosa_, p. 225.


+WINTER KEY TO THE SPECIES OF CATALPA+

   a. Fruiting capsules about 1/4 inch thick; seeds with
   _pointed_, fringed wings at each end; branches rather crooked
   and straggling; bark thin, separating into thin scales on the
   trunk. _C. bignonioides_, p. 227.

   aa. Fruiting capsules about 1/2 inch thick, seeds with
   _rounded_, wide-fringed wings at each end; branches not
   crooked and straggling; bark thick, separating into thick
   scales on the trunk. _C. speciosa_, p. 225.


[Illustration: +Hardy Catalpa+

   1. Winter twig, × 1.
   2. Leaf, × 1/4.
   3. Panicle of flowers, × 3/8.
   4. Fruit, × 1/2.
   5. Seed, × 1.]


+BIGNONIACEAE+

+Hardy Catalpa+

_Catalpa speciosa Warder._


HABIT.--A tree 50-75 feet high, with a short, often crooked trunk and a
broad, rounded crown of slender, spreading branches and thick
branchlets.

LEAVES.--Opposite or whorled, simple, 8-12 inches long, 6-8 inches broad;
heart-shaped; entire or sometimes slightly lobed; thick and firm;
glabrous, dark green above, downy beneath, with clusters of dark,
nectariferous glands in the axils of the primary veins, turning black
and falling with the first severe frost; petioles long, stout, terete.

FLOWERS.--June-July, after the leaves are full grown; perfect; borne on
slender, purplish pedicels in open, few-flowered panicles 5-6 inches
long; calyx 2-lobed, purple; corolla white with inconspicuous yellow
spots, campanulate, 5-lobed, 2-1/2 inches broad; stamens 2, staminodia
3; ovary 2-celled.

FRUIT.--Ripens in early autumn; slender, 2-celled, cylindrical capsule
10-20 inches long and about 1/2 inch thick; hangs on tree all winter,
opening in spring before falling; seeds light brown, 1 inch long, with
rounded, wide-fringed wings at each end.

WINTER-BUDS.--Terminal bud absent; lateral buds brownish, globose,
inconspicuous.

BARK.--Twigs greenish, often with purple tinge, becoming orange or
red-brown and covered with a slight bloom the first winter, finally
darker with age; thick, red-brown, broken into thick scales on the
trunk.

WOOD.--Light, soft, weak, coarse-grained, light brown, with very thin,
almost white sapwood; very durable in contact with the soil.

NOTES.--A native of Illinois, Indiana, and the states adjoining on the
south, but much planted in Michigan as a shade and ornamental tree.
Closely resembles _C. bignonioides_, but is a larger and hardier tree.


[Illustration: +Catalpa+

   1. Winter twig, × 1.
   2. Leaf, × 3/8.
   3. Panicle of flowers, × 1/3.
   4. Fruit, × 1/2.
   5. Seed, × 1.]


+BIGNONIACEAE+

+Catalpa+

_Catalpa bignonioides Walt._ [_Catalpa catalpa (L.) Karst._]


HABIT.--A tree 40-30 feet high, with a short, thick trunk and a broad,
irregular crown of long, crooked branches and coarse, upright
branchlets.

LEAVES.--Opposite or whorled, simple, 5-8 inches long, 4-5 inches broad;
heart-shaped; entire or sometimes slightly lobed; thin and firm;
glabrous, light green above, downy beneath, with dark, nectariferous
glands in the axils of the primary veins, turning black and falling with
the first severe frost; petioles long, stout, terete.

FLOWERS.--June-July, after the leaves are full grown; perfect; borne on
slender, hairy pedicels in compact, many-flowered panicles 8-10 inches
long; calyx 2-lobed, green or purple; corolla white with yellow spots,
campanulate, 5-lobed, 1-1/2 inches broad; stamens 2, staminodia 3; ovary
2-celled.

FRUIT.--Ripens in early autumn; slender, 2-celled, cylindrical capsule
8-20 inches long and about 1/4 inch thick; hangs on tree all winter,
opening in spring before falling; seeds silvery gray, 1 inch long, with
pointed, fringed wings at each end.

WINTER-BUDS.--Terminal bud absent; lateral buds, brownish, globose,
inconspicuous.

BARK.--Twigs greenish purple, becoming red-brown and marked by a network
of thin, flat ridges; thin, red-brown on the trunk, separating into
large, thin, irregular scales.

WOOD.--Light, soft, weak, coarse-grained, light brown, with very thin,
whitish sapwood; very durable in contact with the soil.

NOTES.--A native of the Lower Mississippi River Basin, but naturalized in
southern Michigan, where it is a popular shade and ornamental tree.
Foliage appears very tardily in spring.


[Illustration: +Sheepberry. Nannyberry+

   1. Winter twig, with leaf buds, × 1.
   2. Winter twig, with flower bud, × 1.
   3. Leaf, × 3/4.
   4. Flower, enlarged.
   5. Fruiting branchlet, × 1/2.]


+CAPRIFOLIACEAE+

+Sheepberry. Nannyberry+

_Viburnum lentago L._


HABIT.--A low tree or shrub 15-25 feet high, with a short trunk 6-10
inches in diameter; numerous tortuous branches form a wide, compact,
rounded crown.

LEAVES.--Opposite, simple, 2-4 inches long, one-half as broad; ovate to
suborbicular; finely and sharply serrate; thick and firm; lustrous,
bright green above, pale and marked with tiny black dots beneath;
petioles broad, grooved, more or less winged, about 1 inch long.

FLOWERS.--May-June, after the leaves; perfect; small; cream-white, borne
in stout-branched, scurfy, flat, terminal cymes 3-5 inches across; calyx
tubular, 5-toothed; corolla 5-lobed, cream color or white, 1/4 inch
across; stamens 5, with yellow anthers; ovary 1-celled, with short,
thick, green style and broad stigma.

FRUIT.--September; a fleshy drupe, 1/2 inch long, ovoid, flattened,
blue-black, borne in few-fruited, red-stemmed clusters; stone oval,
flat, rough; flesh sweet, edible.

WINTER-BUDS.--Leaf-buds narrow, acute, red, scurfy-pubescent, 1/2 inch
long; flower-buds swollen at the base, with spire-like apex, grayish
with scurfy pubescence, 3/4 inch long.

BARK.--Twigs at first light green, rusty-pubescent, becoming dark
red-brown; red-brown on old trunks and broken into small, thick plates.

WOOD.--Heavy, hard, close-grained, ill-smelling, dark orange-brown, with
thin, whitish sapwood.

DISTRIBUTION.--Frequent throughout the state.

HABITAT.--Prefers rich, moist soil along the borders of forests;
roadsides; river-banks.

NOTES.--Too small for street use. Propagated from seed or by cuttings.




FOOTNOTES:

[Footnote A: See page xviii.]

[Footnote B: See page xviii.]

[Footnote C: Although formerly classed under PINACEAE, recent
investigations show it to be the type of a distinct family.]

[Footnote D: It is not intended that this key shall serve as a means of
identification of any species of _Salix_ found in Michigan, but it has
added simply to give a ready comparison of the four species which are
described.]

[Footnote E: It is difficult to distinguish between these species in the
absence of summer characters. If leaves can be found on or beneath a
tree which is sufficiently segregated from similar trees as to avoid any
chance for error, the summer key on the opposite page may be used.]

[Footnote F: A discussion has recently arisen as to whether _Betula
lenta_ actually exists in the state, some botanists preferring the name
_B. alleghanensis Britt._ for the tree we have so long called Black
Birch. Pending further investigation the authors have thought best to
retain the old name.

Ref.--Britton: North American Trees, pp. 257-8.]

[Footnote G: [1] means that the acorns mature in the autumn of the first
season, hence mature acorns will not be found on the tree, but on the
ground beneath the tree.

[2] means that the acorns mature in the autumn of the second season,
hence immature acorns will be found on the last season's twigs, and
mature acorns on the ground beneath the tree.]




+GLOSSARY+

_With page references to explanatory figures._


_Abortion._ Imperfect development or non-development of an organ or
part.

_Acuminate._ Gradually tapering to the apex. Page XII.

_Acute._ Terminating with a sharp angle. Page XII.

_Alternate._ Said of leaves, branches, buds, etc., scattered singly
along the stem; not opposite.

_Androgynous._ Composed of both staminate and pistillate flowers.

_Anterior._ The front side of a flower, remote from the axis of
inflorescence.

_Anther._ The part of a stamen which bears the pollen. Page xiii.

_Apetalous._ Without petals.

_Apex._ The top, as the tip of a bud or the end of a leaf which is
opposite the petiole.

_Apiculate._ Ending in a short-pointed tip.

_Appressed._ Lying close and flat against.

_Aromatic._ Fragrant; with an agreeable odor.

_Axil._ The upper one of the two angles formed by the juncture of a leaf
with a stem.

_Axillary._ Situated in an axil.


_Bark._ The outer covering of a trunk or branch.

_Bearded._ Bearing a long, bristle-like appendage, or furnished with
long or stiff hairs.

_Berry._ A fruit which is fleshy throughout.

_Bi-pinnate._ Twice pinnate.

_Blade._ The expanded portion of a leaf, etc.

_Bloom._ A powdery or waxy substance easily rubbed off.

_Bract._ A more or less modified leaf subtending a flower or belonging
to an inflorescence.

_Branch._ A secondary division of a trunk.

_Branchlet._ A small branch.

_Bud._ An undeveloped stem or branch, with or without scales.

_Bud-scales._ Modified leaves covering a bud.

_Bundle-scars._ Dots on the surface of a leaf-scar, which are scars left
by the fibro-vascular bundles which run through the petiole into the
blade of the leaf. Page XVI.

_Bur._ A spiny fruit.


_Calyx._ The outer part of a perianth, usually green in color. Page
xiii.

_Campanulate._ Bell-shaped.

_Capsule._ A dry fruit of more than one carpel which splits at maturity
to release the seeds.

_Carpel._ A simple pistil, or one member of a compound pistil.

_Catkin._ A spike of unisexual flowers, each subtended by a bract, and
usually deciduous in one piece.

_Chambered._ Said of pith which is interrupted by hollow spaces.

_Ciliate._ Fringed with hairs on the margin.

_Cinereous._ Ash-gray color.

_Claw._ The narrow, stalk-like base of a petal, sepal, etc.

_Cleft._ Cut about half-way to the middle.

_Cluster._ A group of two or more organs (flowers, fruit, etc.) on a
plant at a node or end of a stem.

_Compound._ Composed of two or more similar parts united into a whole.
_Compound leaf_, one divided into separate leaflets.

_Cone._ A fruit with woody, overlapping scales.

_Conical._ Cone-shaped, largest at the base and tapering to the apex.

_Connective._ The portion of a stamen which connects the two cells of
the anther.

_Cordate._ Heart-shaped. Page XII.

_Coriaceous._ Leather-like in texture.

_Corky._ Made of, or like cork.

_Corolla._ The inner part of a perianth, usually bright colored. Page
XIII.

_Corymb._ A flower-cluster in which the axis is shortened and the
pedicels of the lower flowers lengthened, forming a flat-topped
inflorescence, the marginal flowers blooming first. Page XIV.

_Corymbose._ Arranged in corymbs.

_Crenate._ Dentate, with the teeth much rounded. Page XIII.

_Crenulate._ Finely crenate.

_Crown._ The upper part of a tree, including the living branches with
their foliage.

_Cutting._ A piece of the stem, root or leaf which, if cut off and
placed in contact with the soil, will form new roots and buds,
reproducing the parent plant.

_Cyme._ A broad and flattish inflorescence, the central flowers of which
bloom first. Page XIV.

_Cymose._ Arranged in cymes.


_Deciduous._ Not persistent; falling away, as the leaves of a tree in
autumn.

_Decurrent._ Said of a leaf which extends down the stem below the point
of fastening.

_Decussate._ Alternating in pairs at right angles.

_Dehiscent._ Opening by valves or slits.

_Deltoid._ Delta-shaped.

_Dentate._ Toothed, with the teeth usually pointed and directed outward.
Page XIII.

_Depressed._ Somewhat flattened from above.

_Dichotomous._ Branching regularly in pairs.

_Digitate._ Said of a compound leaf in which the leaflets are borne at
the apex of the petiole; finger-shaped.

_Dioecious._ Unisexual, with staminate and pistillate flowers on
different individuals.

_Distribution._ The geographical extent and limits of a species.

_Divergent._ Said of buds, cones, etc., which point away from the twig,
or of pine needles, etc., which spread apart.

_Dorsal._ Pertaining to the back or outer surface of an organ.

_Downy._ Covered with fine hairs.

_Drupe._ A fleshy or pulpy fruit in which the inner portion is hard or
stony.


_Ellipsoid._ An elliptical solid.

_Elliptical._ Oval or oblong with regularly rounded ends. Page XII.

_Emarginate._ Notched at the apex. Page XII.

_Entire._ Without divisions, lobes or teeth.

_Excrescences._ Warty outgrowths or protuberances.

_Exfoliate._ To cleave off, as of the outer layers of bark.


_Falcate._ Scythe-shaped.

_Fascicle._ A compact cluster of leaves or flowers.

_Fascicled._ Arranged in fascicles.

_Fastigiate._ Said of branches which are erect and near together.

_Feather-veined._ Having veins extending from the midrib to the margin,
feather-wise.

_Fertile._ Capable of bearing fruit.

_Fertilization._ The mingling of the contents of a male (pollen) and
female (ovule) cell.

_Filament._ The part of a stamen which bears the anther. Page XIII.

_Filamentose_ or _Filamentous_. Composed of threads or filaments.

_Flaky._ With loose scales easily rubbed off (bark).

_Fleshy._ Succulent; juicy.

_Flower._ An axis bearing stamens or pistils or both (calyx and corolla
usually accompany these).

_Fluted._ With rounded ridges.

_Fruit._ The part of a plant which bears the seed.


_Germinate._ To sprout, as of a seed.

_Gibbous._ Swollen on one side.

_Glabrous._ Neither rough, pubescent, nor hairy; smooth.

_Gland._ Secreting surface or structure; a protuberance having the
appearance of such an organ.

_Glandular._ Bearing glands.

_Glaucous._ Covered or whitened with a bloom.

_Globose._ Spherical or nearly so.

_Globular._ Nearly globose.

_Gregarious._ Growing in groups or colonies.


_Habit._ The general appearance of a plant, best seen from a distance.

_Habitat._ The place where a plant naturally grows, as in water, clay
soil, marsh, etc.

_Hairy._ With long hairs.

_Halberd-shaped._ Like an arrow-head, but with the basal lobes pointing
outward nearly at right angles. Page XII.

_Heartwood._ The dead central portion of the trunk or large branch of a
tree.

_Hirsute._ Covered with rather coarse or stiff hairs.

_Hoary._ Gray-white with a fine, close pubescence.

_Homogeneous._ Uniform; composed of similar parts or elements.

_Hybrid._ A cross between two nearly related species, formed by the
action of the pollen of one upon the pistil of the other, yielding an
intermediate form.


_Imbricate._ Overlapping, like the shingles on a roof.

_Indehiscent._ Not opening by valves or slits; remaining persistently
closed.

_Indigenous._ Native and original to a region.

_Inflorescence._ The flowering part of a plant, and especially its
arrangement.

_Internode._ The portion of a stem between two nodes.

_Involucral._ Pertaining to an involucre.

_Involucre._ A circle of bracts surrounding a flower or cluster of
flowers.


_Keeled._ With a central ridge like the keel of a boat.


_Laciniate._ Cut into narrow, pointed lobes.

_Lanceolate._ Lance-shaped, broadest above the base and tapering to the
apex, but several times longer than wide. Page xii.

_Lateral._ Situated on the side of a branch.

_Leaf._ The green expansions borne by the branches of a tree, consisting
of a blade with or without a petiole.

_Leaflet._ One of the small blades of a compound leaf.

_Leaf-scar._ The scar left on a twig by the falling of a leaf. Page XVI.

_Legume._ A pod-like fruit composed of a solitary carpel and usually
splitting open by both sutures (_Leguminosae_).

_Lenticels._ Corky growths on young bark which admit air to the interior
of a twig or branch.

_Linear._ Long and narrow, with parallel edges (as pine needles). Page
XII.

_Lobe._ Any division of an organ, especially if rounded.

_Lobed._ Provided with a lobe or lobes. Page XIII.

_Lustrous._ Glossy; shining.


_Membranaceous._ Thin and somewhat translucent.

_Midrib._ The central vein of a leaf or leaflet.

_Monoecious._ Unisexual, with staminate and pistillate flowers on the
same individual.

_Mucilaginous._ Slimy; resembling or secreting mucilage or gum.

_Mucronate._ Tipped with a small, abrupt point. Page XII.


_Naked_. Lacking organs or parts which are normally present in related
species or genera.

_Naturalized_. Said of introduced plants which are reproducing by
self-sown seeds.

_Nectariferous_. Producing nectar.

_Node_. The place upon a stem which normally bears a leaf or whorl of
leaves.

_Nut_. A hard and indehiscent, 1-celled, 1-seeded fruit.

_Nutlet_. A diminutive nut.


_Oblanceolate_. Lanceolate, with the broadest part toward the apex. Page
XII.

_Oblique_. Slanting, or with unequal sides.

_Oblong_. Longer than broad, with sides approximately parallel. Page
XII.

_Obovale_. Ovate, with the broadest part toward the apex. Page XII.

_Obovoid_. An ovate solid with the broadest part toward the apex.

_Obtuse_. Blunt or rounded at the apex. Page XII.

_Opaque_. Dull; neither shining nor translucent.

_Opposite_. Said of leaves, branches, buds, etc., on opposite sides of a
stem at a node.

_Orbicular_. Circular. Page XII.

_Oval_. Broadly elliptical. Page XII.

_Ovary_. The part of a pistil that contains the ovules. Page XIII.

_Ovate_. Egg-shaped, with the broad end basal. Page XII.

_Ovoid_. Solid ovate or solid oval.

_Ovule_. The part of a flower which after fertilization becomes the
seed.


_Palmate_. Radiately lobed or divided; hand-shaped.

_Panicle_. A loose, irregularly compound inflorescence with pedicellate
flowers. Page XIV.

_Paniculate_. Arranged in panicles or resembling a panicle.

_Papilionaceous_. Butterfly-like, as in flowers of the _Leguminosae_.

_Pedicel_. The stalk of a single flower in a compound inflorescence.

_Pedicellate_. Borne on a pedicel.

_Peduncle_. A primary flower-stalk, supporting either a cluster or a
solitary flower.

_Pendent._ Hanging downward.

_Pendulous._ More or less hanging or declined.

_Perfect._ Said of a flower with both stamens and pistil. Page XIII.

_Perianth._ The calyx and corolla of a flower considered as a whole.

_Persistent._ Long-continuous, as leaves through the winter, calyx on
the fruit, etc.

_Petal._ One of the divisions of a corolla. Page XIII.

_Petiolate._ Having a petiole.

_Petiole._ The stem or stalk of a leaf.

_Petiolulate._ Having a petiolule.

_Petiolule._ The stem or stalk of a leaflet.

_Pilose._ Hairy with long, soft hairs.

_Pinnate._ Compound, with the leaflets arranged along both sides of a
common petiole.

_Pistil._ The seed-bearing organ of a flower, normally consisting of
ovary, style and stigma. Page XIII.

_Pistillate._ Provided with a pistil, but usually without stamens.

_Pith._ The softer central part of a twig or stem. Page XVI.

_Pollen._ The fecundating grains borne in the anther.

_Polygamo-dioecious._ Sometimes perfect, sometimes unisexual, both forms
borne on different individuals.

_Polygamo-monoecious._ Sometimes perfect, sometimes unisexual, both
forms borne on the same individual.

_Polygamous._ Sometimes perfect, sometimes unisexual, both forms borne
on the same or on different individuals.

_Pome._ A fleshy fruit, as the apple.

_Posterior._ The back side of a flower, next to the axis of
inflorescence.

_Prickle._ A small spine growing from the bark.

_Puberulent._ Minutely pubescent.

_Puberulous._ Minutely pubescent.

_Pubescence._ A covering of short, soft hairs.

_Pubescent._ Covered with short, soft hairs.

_Punctate._ Dotted with translucent or colored dots or pits.


_Raceme._ A simple inflorescence of flowers on pedicels of equal length
arranged on a common, elongated axis (rachis). Page XIV.

_Racemose._ Resembling a raceme.

_Rachis._ The central axis of a spike or raceme of flowers or of a
compound leaf.

_Recurved._ Curved downward or backward.

_Reticulate._ Netted.

_Rough._ Harsh to the touch; pubescent.

_Rugose._ Wrinkled.


_Samara._ An indehiscent winged fruit.

_Sapwood._ The living outer portion of a trunk or large branch of a tree
between the heartwood and the bark.

_Scales._ Small modified leaves, usually thin and scarious, seen in buds
and cones; the flakes into which the outer bark often divides.

_Scaly._ Provided with scales.

_Scarious._ Thin, dry, membranaceous; not green.

_Scurfy._ Covered with small bran-like scales.

_Seed._ The ripened ovule.

_Sepal._ One of the divisions of a calyx. Page XIII.

_Serrate._ Toothed, the teeth sharp and pointing forward. Page XIII.

_Sessile._ Without a stalk.

_Shrub._ A bushy, woody growth, usually branched at or near the base,
less than 15 feet in height.

_Simple._ Of one piece; not compound.

_Sinuate._ Strongly wavy. Page XIII.

_Sinuous._ In form like the path of a snake.

_Sinus._ The cleft or space between two lobes.

_Smooth._ Smooth to the touch; not pubescent.

_Spatulate._ Wide and rounded at the apex, but gradually narrowed
downward. Page XII.

_Spike._ A simple inflorescence of sessile flowers arranged on a common,
elongated axis (rachis). Page XIV.

_Spine._ A sharp woody outgrowth from a stem.

_Spray._ The aggregate of smaller branches and branchlets.

_Stamen._ The pollen-bearing organ of a flower, normally consisting of
filament and anther. Page XIII.

_Staminate._ Provided with stamens, but usually without pistils.

_Staminodium_. A sterile stamen.

_Sterile_. Unproductive, as a flower without pistil, or a stamen without
anther.

_Stigma_. The part of a pistil which receives the pollen. Page XIII.

_Stipules_. Leaf-like appendages on either side of a leaf at the base of
the petiole.

_Stipule-scar_. The scar left by the fall of a stipule. Page XV.

_Striate_. Marked with fine longitudinal stripes or ridges.

_Strobile_. A cone.

_Style_. The part of a pistil connecting ovary with stigma. Page XIII.

_Sub_-. A prefix applied to many botanical terms, indicating somewhat or
slightly.

_Subtend_. To lie under or opposite to.

_Sucker_. A shoot arising from a subterranean part of a plant.

_Superposed_. Placed above, as one bud above another at a node.

_Suture_. A junction or line of dehiscence.


_Terete_. Circular in cross-section.

_Terminal_. Situated at the end of a branch.

_Ternate_. In threes.

_Tetrahedral_. Having, or made up of, four faces (triangles).

_Thorn_. A stiff, woody, sharp-pointed projection.

_Tolerant_. Capable of enduring more or less heavy shade.

_Tomentose_. Densely pubescent with matted wool.

_Toothed_. With teeth or short projections.

_Torus_. The part of the axis of a flower which bears the floral organs.

_Transverse_. Said of a wood section made at right angles with the axis
of the stem; across the grain.

_Tree_. Usually defined as a plant with a woody stem, unbranched at or
near the base, reaching a height of at least 15 feet.

_Trunk_. The main stem of a tree.

_Turbinate_. Top-shaped.


_Umbel_. A simple inflorescence of flowers on pedicels which radiate
from the same point. Page XIV.

_Umbellate_. Arranged in umbels.

_Undulate_. With a wavy margin or surface. Page XIII.

_Unisexual_. Of one sex, either staminate or pistillate; not perfect.


_Veins._ Threads of fibro-vascular tissue in a leaf, petal, or other
flat organ.

_Villose_ or _Villous_. Covered with long, soft hairs.

_Viscid._ Glutinous; sticky.


_Whorl._ An arrangement of leaves or branches in a circle round an axis.

_Wood._ The hard part of a stem lying between the pith and the bark.

_Woolly._ Covered with long and matted or tangled hairs.




INDEX TO THE ARTIFICIAL KEYS


   Summer Keys:

   Key to the genera, xxi.
   Key to the species of Acer, 172.
   Key to the species of Aesculus, 194.
   Key to the species of Betula, 84.
   Key to the species of Carya, 66.
   Key to the species of Catalpa, 222.
   Key to the species of Cornus, 202.
   Key to the species of Fraxinus, 210.
   Key to the species of Juglans, 60.
   Key to the species of Picea, 18.
   Key to the species of Pinus, 4.
   Key to the species of Populus, 44.
   Key to the species of Prunus, 152.
   Key to the species of Pyrus, 142.
   Key to the species of Quercus, 96.
   Key to the species of Salix, 34.
   Key to the species of Ulmus, 122.


   Winter Keys:

   Key to the genera, xxvii.
   Key to the species of Acer, 174.
   Key to the species of Aesculus, 195.
   Key to the species of Betula, 85.
   Key to the species of Carya, 67.
   Key to the species of Catalpa, 223.
   Key to the species of Cornus, 203.
   Key to the species of Fraxinus, 211.
   Key to the species of Juglans, 61.
   Key to the species of Picea, 19.
   Key to the species of Pinus, 5.
   Key to the species of Populus, 45.
   Key to the species of Prunus, 153.
   Key to the species of Pyrus, 143.
   Key to the species of Quercus, 98.
   Key to the species of Salix, 34.
   Key to the species of Ulmus, 123.




INDEX TO THE TREES


   Abies balsamea, 27.

   Acacia, Three-thorned, 165.

   Acer dasycarpum, 185.
     negundo, 193.
     nigrum, 183.
     pennsylvanicum, 177.
     platanoides, 189.
     pseudo-platanus, 191.
     rubrum, 187.
     saccharinum, 181, 185.
     saccharum, 181, 189.
     saccharum nigrum, 183.
     spicatum, 179.

   Aesculus glabra, 199.
     hippocastanum, 197.
     hippocastanum, v. flòre plèno, 197.

   Ailanthus, 171.
     glandulosa, 171.

   Almondleaf Willow, 39.

   Alternate-leaved Dogwood, 207.

   Amelanchier canadensis, 149.

   American Crab, 145.
     Elm, 127.

   Arborvitae, 31.

   Ash, Black, 221.
     Blue, 219.
     Green, 217.
     Mountain, 147.
     Red, 215.
     White, 213.

   Ash-leaved Maple, 193.

   Aspen, 49.
     Largetooth, 51.

   Austrian Pine, 11.


   Balm of Gilead, 53.
     Hairy, 55.

   Balsam, 53, 55.
     Fir, 27.

   Basswood, 201.

   Beech, 93.
     Blue, 83.
     Water, 83.
     White, 93.

   Betula alba papyrifera, 91.
     alleghanensis, 87.
     lenta, 87.
     lutea, 89.
     papyrifera, 91.

   Birch, Black, 87.
     Canoe, 91.
     Cherry, 87.
     Gray, 89.
     Paper, 91.
     Sweet, 87.
     White, 91.
     Yellow, 89.

   Bitternut Hickory, 79.

   Black Ash, 221.
     Birch, 87.
     Cherry, 155.
     Gum, 209.
     Jack, 119.
     Locust, 169.
     Maple, 183.
     Oak, 115, 117.
     Pine, 11.
     Spruce, 23.
     Sugar Maple, 183.
     Walnut, 65.
     Willow, 37.

   Blue Ash, 219.
     Beech, 83.
     Dogwood, 207.

   Boxelder, 193.

   Boxwood, 205.

   Brittle Willow, 41.

   Buckeye, Ohio, 199.

   Bur Oak, 103.

   Butternut, 63.

   Buttonball-tree, 141.

   Button-wood, 141.


   Canada Plum, 161.

   Canoe Birch, 91.

   Carpinus caroliniana, 83.

   Carya alba, 69, 73.
     amara, 79.
     cordiformis, 79.
     glabra, 75, 77.
     laciniosa, 71.
     microcarpa, 75.
     ovata, 69.
     porcina, 77.
     sulcata, 71.
     tomentosa, 73.

   Castanea dentata, 95.
     sativa, v. americana, 95.
     vesca, v. americana, 95.

   Catalpa, 227.
     bignonioides, 225, 227.
     catalpa, 227.
     Hardy, 225.
     speciosa, 225.

   Cedar, Red, 33.
     White, 31.

   Celtis occidentalis, 131.

   Cercis canadensis, 167.

   Cherry Birch, 87.

   Cherry, Black, 155.
     Choke, 157.
     Pin, 159.
     Wild Red, 159.

   Chestnut, 95.
     Oak, 107.

   Chinquapin Oak, 107.

   Choke Cherry, 157.

   Coffeetree, 163.
     Kentucky, 163.

   Cork Elm, 129.

   Cornus alternifolia, 207.
     florida, 205.

   Cottonwood, 57.

   Crab, American, 145.
     Sweet, 145.

   Crack Willow, 41.

   Crataegus, 151.
     punctata, 150.


   Dogwood, 205.
     Alternate-leaved, 207.
     Blue, 207.
     Flowering, 205.


   Elm, American, 127.
     Cork, 129.
     Red, 125.
     Rock, 129.
     Slippery, 125.
     Water, 127.
     White, 127.


   Fagus americana, 93.
     atropunicea, 93.
     ferruginea, 93.
     grandifolia, 93.

   Fir, Balsam, 27.
     Scotch, 13.

   Flowering Dogwood, 205.

   Fraxinus americana, 213.
     lanceolata, 217.
     nigra, 221.
     pennsylvanica, 215, 217.
     pennsylvanica lanceolata, 217.
     pubescens, 215,
     quadrangulata, 219.
     sambucifolia, 221.
     virdis, 217.


   Ginkgo, 3.
     biloba, 3.

   Gleditsia triacanthos, 165.

   Gray Birch, 89.

   Green Ash, 217.

   Gum, Black, 209.

   Gymnocladus canadensis, 163.
     dioica, 163.


   Hackberry, 131.

   Hairy Balm of Gilead, 55.

   Hard Maple, 181.

   Hardy Catalpa, 225.

   Haw, 151.

   Hawthorn, 151.

   Hemlock, 29.

   Hickory, Bitternut, 79.
     Mocker Nut, 73.
     Pignut, 77.
     Shagbark, 69.
     Shellbark, 69, 71.
     Small Pignut, 75.

   Hicoria alba, 73.
     glabra, 77.
     glabra, v. odorata, 75.
     laciniosa, 71.
     microcarpa, 75.
     minima, 79.
     odorata, 75.
     ovata, 69.

   Hill's Oak, 115.

   Honey Locust, 165.

   Hornbeam, 81.

   Horse-chestnut, 197.


   Ironwood, 81.


   Jack Pine, 9.

   Judas-tree, 167.

   Juglans cinerea, 63.
     nigra, 65.

   Juniper, Red, 33.

   Juniperus virginiana, 33.


   Kentucky Coffeetree, 163.

   King Nut, 71.


   Largetooth Aspen, 51.

   Larix americana, 17.
     laricina, 17.

   Liriodendron tulipifera, 137.

   Locust, 169.
     Black, 169.
     Honey, 165.

   Lombardy Poplar, 59.


   Maclura aurantiaca, 133.
     pomifera, 133.

   Maidenhair Tree, 3.

   Malus coronaria, 145.

   Maple, Ash-leaved, 193.
     Black, 183.
     Black Sugar, 183.
     Hard, 181.
     Mountain, 179.
     Norway, 189.
     Red, 187.
     Rock, 181.
     Silver, 185.
     Soft, 185, 187.
     Striped, 177.
     Sugar, 181.
     Sycamore, 191.

   Mocker Nut Hickory, 73.

   Moosewood, 177.

   Morus rubra, 135.

   Mountain Ash, 147.
     Maple, 179.

   Mulberry, Red, 135.


   Nannyberry, 229.

   Napoleon's Willow, 43.

   Negundo aceroides, 193.

   Nettle-tree, 131.

   Northern Pin Oak, 115.

   Norway Maple, 189.
     Pine, 15.
     Spruce, 25.

   Nut, King, 71.

   Nyssa multiflora, 209.
     sylvatica, 209.


   Oak, Black, 115, 117.
     Bur, 103.
     Chestnut, 107.
     Chinquapin, 107.
     Hill's, 115.
     Northern Pin, 115.
     Pin, 111.
     Red, 109.
     Scarlet, 113.
     Shingle, 121.
     Swamp, 105.
     Swamp White, 105.
     White, 101.
     Yellow, 107, 117.

   Ohio Buckeye, 199.

   Osage Orange, 133.

   Ostrya virginiana, 81.


   Padus serotina, 155.
     virginiana, 157.

   Paper Birch, 91.

   Pepperidge, 209.

   Picea abies, 25.
     alba, 21.
     canadensis, 21.
     excelsa, 25.
     mariana, 23.
     nigra, 23.

   Pignut Hickory, 77.
     Small, 75.

   Pin Cherry, 159.
     Oak, 111.
     Oak, Northern, 115.

   Pine, Austrian, 11.
     Black, 11.
     Jack, 9.
     Norway, 15.
     Red, 15.
     Scotch, 13.
     Scrub, 9.
     White, 7.

   Pinus austriaca, 11.
     banksiana, 9.
     divaricata, 9.
     laricio austriaca, 11.
     resinosa, 15.
     strobus, 7.
     sylvestris, 13.

   Platanus occidentalis, 141.

   Plum, Canada, 161.
     Red, 161.

   Poplar, Lombardy, 59.
     Tulip, 137.
     White, 47.

   Populus alba, 47.
     balsamifera, 53, 55.
     balsamifera candicans, 55.
     candicans, 55.
     deltoides, 57.
     dilatata, 59.
     fastigiata, 59.
     grandidentata, 51.
     monilifera, 57.
     nigra italica, 59.
     tremuloides, 49.

   Prunus americana, v. nigra, 161.
     nigra, 161.
     pennsylvanica, 159.
     serotina, 155.
     virginiana, 157.

   Pyrus americana, 147.
     coronaria, 145.


   Quercus acuminata, 107.
     alba, 101.
     Alexanderi, 107.
     bicolor, 105.
     coccinea, 113.
     ellipsoidalis, 115.
     imbricaria, 121.
     macrocarpa, 103.
     marilandica, 119.
     muhlenbergii, 107.
     palustris, 111.
     platanoides, 105.
     rubra, 109.
     velutina, 117.


   Red Ash, 215.
     Cedar, 33.
     Cherry, Wild, 159.
     Elm, 125.
     Juniper, 33.
     Maple, 187.
     Mulberry, 135.
     Oak, 109.
     Pine, 15.
     Plum, 161.

   Redbud, 167.

   Robinia pseudo-acacia, 169.

   Rock Elm, 129.
     Maple, 181.


   Salisburia adiantifolia, 3.

   Salix, 35.
     amygdaloides, 39.
     babylonica, 43.
     fragilis, 41.
     nigra, 37.

   Sassafras, 139.
     officinale, 139.
     sassafras, 139.
     variifolium, 139.

   Scarlet Oak, 113.

   Scotch Fir, 13.
     Pine, 13.

   Scrub Pine, 9.

   Serviceberry, 149.

   Shagbark Hickory, 69.

   Sheepberry, 229.

   Shellbark Hickory, 69, 71.

   Shingle Oak, 121.

   Silver Maple, 185.

   Slippery Elm, 125.

   Small Pignut Hickory, 75.

   Soft Maple, 185, 187.

   Sorbus americana, 147.

   Spruce, Black, 23.
     Norway, 25.
     White, 21.

   Striped Maple, 177.

   Sugar Maple, 181.
     Black, 183.

   Swamp Oak, 105.
     White Oak, 105.

   Sweet Birch, 87.
     Crab, 145.

   Sycamore, 141.
     Maple, 191.


   Tamarack, 17.

   Thorn, 151.

   Thorn-apple, 151.

   Three-thorned Acacia, 165.

   Thuja occidentalis, 31.

   Tilia americana, 201.

   Toxylon pomiferum, 133.

   Tree, Maidenhair, 3.
     of Heaven, 171.

   Tsuga canadensis, 29.

   Tulip Poplar, 137.

   Tulip-tree, 137.


   Ulmus americana, 125, 127.
     fulva, 125,
     pubescens, 125.
     racemosa, 129.
     Thomasi, 129.


   Viburnum lentago, 229.

   Walnut, Black, 65.

   Water Beech, 83.
     Elm, 127.

   Weeping Willow, 43.

   Whistlewood, 177.

   White Ash, 213.
     Beech, 93.
     Birch, 91.
     Cedar, 31.
     Elm, 127.
     Oak, 101.
     Oak, Swamp, 105.
     Pine, 7.
     Poplar, 47.
     Spruce, 21.

   White-wood, 137.

   Wild Red Cherry, 159.

   Willow, 35.
     Almondleaf, 39.
     Black, 37.
     Brittle, 41.
     Crack, 41.
     Napoleon's, 43.
     Weeping, 43.


   Yellow Birch, 89.
     Oak, 107, 117.