Kinds of Flowers.—When the petals are entirely separate from each other, as in the Apple-blossom, the flower is said to be polypetalous; when they grow together more or less, as in the Catalpa (Fig. 10), monopetalous; and when the corolla is wanting, as in the flowers of the Oak, apetalous.

When all sides of a flower are alike, as in the Apple-blossom, the flower is regular; when one side of the corolla differs from the other in color, form, or size, as in the Common Locust, or Catalpa, the flower is irregular.

In trees the stamens and pistils are often found in separate flowers; in that case the blossoms containing stamens are called staminate, and those containing pistils pistillate; those that contain both are called perfect. Staminate and pistillate flowers are usually found on the same tree, as in the Oaks, Birches, Chestnut, etc.; in that case the plant is said to be monœcious, and all trees of this kind produce fruit. Sometimes, however, the staminate and pistillate flowers are on separate trees, as in the Willows, which are diœcious; and then only a portion of the trees—those with pistillate flowers—produce fruit.

Arrangement of Flowers.—Flowers, either solitary or clustered, grow in one of two ways; either at the end of the branches, being then called terminal, or in the axils of the leaves, then called axillary. The stem of a solitary flower or the main stem of a cluster is called a peduncle; the stems of the separate blossoms of a cluster are called pedicels. When either the flowers or the clusters are without stems, they are said to be sessile.

Clusters with Pedicellate Flowers.

Raceme, flowers on pedicels of about equal length, scattered along the entire stem. Locust-tree.

Corymb, like a raceme except that the lower flowers have longer stems, making the cluster somewhat flat-topped; the outer flowers bloom first. Hawthorn.

Cyme, in appearance much like a corymb, but it differs in the fact that the central flower blooms first. Alternate-leaved Cornel.

Umbel, stems of the separate flowers about equal in length, and starting from the same point. Garden-cherry.

Panicle, a compound raceme. Catalpa.

Thyrsus, a compact panicle. Horse-chestnut.

Clusters with Sessile or Nearly Sessile Flowers.

Catkin, bracted flowers situated along a slender and usually drooping stem. This variety of cluster is very common on trees. The Willows, Birches, Chestnuts, Oaks, Pines, and many others have their flowers in catkins.

Head, the flowers in a close, usually rounded cluster. Flowering Dogwood.

Fruit.—In this book a single fruit will include all the parts that grow together and contain seeds, whether from a single blossom or a cluster; there will be no rigorous adherence to an exact classification; no attempt made to distinguish between fruits formed from a simple pistil and those from a compound one; nor generally between those formed from a single and those formed from a cluster of flowers. The fruit and its general classification, determined by the parts easily seen, is all that will be attempted.

As stated before, it is hoped that this volume will not end the student's work in the investigation of natural objects, but that the amount of information here given will lead to the desire for much more.

Berry will be the term applied to all fleshy fruits with more than one seed buried in the mass. Persimmon, Mulberry, Holly. The pome or Apple-pome differs from the berry in the fact that the seeds are situated in cells formed of hardened material. Apple, Mountain-ash. The Plum or Cherry drupe includes all fleshy fruits with a single stony-coated part, even if it contains more than one seed. Peach, Viburnum, China-tree. In some cases, when there is but one seed in the flesh and that not stony-coated, it will be called a drupe-like berry.

The dry drupe is like the Cherry drupe except that the flesh is much harder. The fruit of the Walnut, Hickory, and Sumac.

The inner hard-coated parts of these and some others will be called nuts. If the nut has a partial scaly covering, as in the Oaks, the whole forms an acorn. If the coating has spiny hairs, as in the Chestnut and Beechnut, the whole is a bur. The coating in these cases is an involucre. If the coating or any part of the fruit has a regular place for splitting open, it is dehiscent (Chestnut, Hickory-nut); if not, indehiscent (Black Walnut).

Dry fruits with spreading, wing-like appendages, as in the Ash (Fig. 11), Maple (Fig. 12), Elm (Fig. 13), and Ailanthus, are called samaras or keys.

Dry fruits, usually elongated, containing generally several seeds, are called pods. If there is but one cell and the seeds are fastened along one side, Pea-like pods, or legumes. Locust. The term capsule indicates that there is more than one cell. Catalpa, Hibiscus.

All the dry, scaly fruits, usually formed by the ripening of some sort of catkin of flowers, will be included under the term cone. Pine, Alder, Magnolia. If the appearance of the fruit is not much different from that of the cluster of flowers, as in the Hornbeams, Willows, and Birches, the term catkin will be retained for the fruit also. The scales of a cone may lap over each other; they are then said to be imbricated or overlapping, (Pine); or they may merely touch at their edges, when they are valvate (Cypress). When cones or catkins hang downward, they are pendent. If the scales have projecting points, these points are spines if strong, and prickles if weak. The parts back of the scales are bracts; these often project beyond the scales, when they are said to be exserted. Sometimes the exserted bracts are bent backward; they are then said to be recurved or reflexed.

Chapter V.
Winter Study of Trees.

Many of the peculiarities of trees can be studied much better during the winter and early spring than at any other time of the year. The plan of branching, the position, number, size, form, color, and surface of buds, as well as the arrangement of the leaves within the bud and the peculiarities of the scales that cover them, are points for winter investigation.

General Plan of Branching.—There are two distinct and readily recognized systems of branching. 1. The main stem is excurrent (Fig. 3) when the trunk extends as an undivided stem throughout the tree to the tip; this causes the spire-like or conical trees so common among narrow-leaved evergreens. 2. The main stem is deliquescent (Fig. 4) when the trunk divides into many, more or less equal divisions, forming the broad-topped, spreading trees. This plan is the usual one among deciduous trees. A few species, however, such as the Sweet Gum and the Sugar-maple, show the excurrent stem while young, yet even these have a deliquescent stem later in life. The English Maple and the Apple both have a deliquescent stem very early.

All the narrow-leaved evergreens, and many of the broad-leaved trees as well, show what is called definite annual growths; that is, a certain amount of leaf and stem, packed up in the winter bud, spreads out and hardens with woody tissue early in the year, and then, no matter how long the season remains warm, no additional leaves or stem will grow. The buds for the next year's growth then form and often become quite large before autumn.

There are many examples among the smaller plants, but rarely one among the trees, of indefinite annual growth; that is, the plant puts forth leaves and forms stems throughout the whole growing-season. The common Locust, the Honey-locust, and the Sumacs are illustrations.

Buds.—Buds are either undeveloped branches or undeveloped flowers. They contain within the scales, which usually cover them, closely packed leaves; these leaves are folded and wrinkled in a number of different ways that will be defined at the end of this chapter.

Position and Number.—While the axils of the leaves and the ends of the stems are the ordinary places for the buds, there are many peculiarities in regard to their exact position, number, etc., that render them very interesting for winter study. Sometimes there are several to the single leaf. In the Silver Maple there are buds on each side of the true axillary one; these are flower-buds, and during the winter they are larger than the one which produces the branch. The Butternut (Fig. 14) and the Walnut have several above each other, the upper one being the largest and at quite a distance from the true axil. In these cases the uppermost is apt to grow, and then the branch is said to be extra-axillary. In the Sycamore the bud does not show while the leaf remains on the tree, as it is in the hollow of the leafstalk. In the winter the bud has a ring-like scar entirely around it, instead of the moon-shaped scar below as in most trees. The Common Locust has several buds under the leafstalk and one above it in the axil. This axillary bud may grow during the time the leaf remains on the tree, and afterward the growth of the strongest one of the others may give the tree two branches almost together.

Some plants form extra buds especially when they are bruised or injured; those which have the greatest tendency to do so are the Willows, Poplars, and Elms. Such buds and growths are called adventitious. By cutting off the tops or pollarding such trees, a very great number of adventitious branches can be made to grow. In this way the Willow-twigs used for baskets are formed. Adventitious buds form the clusters of curious thorns on the Honey-locust and the tufts of whip-like branches on the trunks and large limbs of the Elms.

In trees the terminal bud and certain axillary ones, differing according to the species or variety of tree, are, during the winter, much larger than the rest. These are the ones which naturally form the new growth, and upon their arrangement the character of branching and thus the form of the tree depend. Each species has some peculiarity in this regard, and thus there are differences in the branching of all trees. In opposite-leaved plants the terminal bud may be small and weak, while the two buds at its side may be strong and apt to grow. This causes a forking of the branches each year. This plan is not rare among shrubs, the Lilac being a good example.

Bud-Scales.—The coverings of buds are exceedingly varied, and are well worthy of study and investigation. The large terminal buds of the Horse-chestnut, with their numerous scales, gummy on the outside to keep out the dampness, and hairy within to protect them from sudden changes of temperature, represent one extreme of a long line; while the small, naked, and partly buried buds of the Honey-locust or the Sumac represent the other end.

The scales of many buds are merely extra parts formed for their protection, and fall immediately after the bursting of the buds; while other buds have the stipules of the leaves as bud-scales; these remain on the twigs for a time in the Tulip-tree, and drop immediately in the Magnolia.

Forms of Buds.—The size of buds varies greatly, as before stated, but this difference in size is no more marked than the difference in form. There is no better way to recognize a Beech at any time of the year than by its very long, slender, and sharp-pointed buds. The obovate and almost stalked buds of the Alders are also very conspicuous and peculiar. In the Balsam Poplar the buds are large, sharp-pointed, and gummy; in the Ailanthus they cannot be seen.

All the things that might be learned from a small winter twig cannot be shown in an engraving, but the figures here given illustrate some of the facts easily determined from such specimens. The first twig (Ash) had opposite leaves and is 3 years old (the end of each year's growth is marked by dotted lines on all the figures); the year before last it had 6 leaves on the middle portion; last year it had 8 leaves on the end portion and 12 on the side shoots of the middle portion. The buds near the end of the annual growth are strongest and are most apt to grow. The specimen illustrated was probably taken from the end of a branch of a rather young and luxuriantly growing tree. Thus the Ash must have quite a regular growth and form a regularly outlined tree.

The second twig (Sweet Gum) shows 7 years' growth and is probably a side shoot from more or less within the tree-top. It is stunted in its growth by the want of light and room. The leaves were alternate.

The third twig (Sycamore) also had alternate leaves; the pointed buds must have been under the leafstalks, as the leaf-scars show as rings around the buds. The larger branch grew three years ago. From the specimen one judges that the Sycamore is quite an irregularly formed tree. The twig had 11 leaves last year.

The fourth twig (Silver Maple) shows that the plant had opposite leaves, and supernumerary buds at the sides of the true axillary ones; the true axillary buds are smaller than those at the sides. It would, in such cases, be reasonable to suppose that the supernumerary buds were floral ones, and that the plant blooms before the leaves expand. The annual growths are quite extended; two years and a part of the third make up the entire twig. If it was cut during the winter of 1891-92, it must have had leaves on the lower part in 1889 and 12 leaves on the middle portion in 1890, as well as probably 4 on the lower portion on the side shoots. Last year it had 14 leaves on the end portion, two at least on each side shoot below, making 24 in all.

Folding of Leaves in the Bud.

There are some peculiarities in the arrangement of leaves in the bud which can be investigated only in the early spring. The common plans among trees are—Inflexed: blade folded crosswise, thus bringing it upon the footstalk. Tulip-tree. Conduplicate: blade folded along the midrib, bringing the two halves together. Peach. Plicate: folded several times lengthwise, like a fan. Birch. Convolute: rolled edgewise from one edge to the other. Plum. Involute: both edges rolled in toward the midrib on the upper side. Apple. Revolute: both edges rolled backward. Willow. Obvolute: folded together, but the opposite leaves half inclosing each other. Dogwood.

Chapter VI.
The Preparation of a Collection.

Three specimens are needed of each kind of tree: one, a branch showing the flowers; another, showing the fruit—one of these, and in many cases both, will show the leaves. The third specimen, cut from a large limb or trunk, shows the bark and the wood. This should be a specimen with a surface so cut as to show the wood in the direction of the silver grain, radial section; with another surface cut in the direction of the annual layers, tangential section; and with a third cut across the grain, cross-section. It should be a specimen old enough to show the change of color in the heart-wood. By taking a limb or trunk 8 inches in diameter, all these points can be secured. A specimen cut as shown in the figure will illustrate all the desired points. Side E F G shows sap-and heart-wood in tangential section; side A B D C shows the same in radial section; end A B F E, in cross-section; and B F G D shows the bark. The central pith is at I; the heart-wood extends from C to J; the sap-wood from J to D. The silver grain is well shown at the end, and the blotches formed by it on the radial section.

By having the piece made smooth, and the upper part down to the center (H) varnished, the appearance of the wood in furniture or inside finish will be illustrated.

The specimens should be as nearly uniform in size as possible. If a limb 8 inches in diameter be taken and a length of 6 inches be cut off, the section A B D C should pass through the line of pith; the section E F G should be parallel with this at a distance from it of two inches; and two inches from the line of pith, the section A E C should be made. The whole specimen will then be 6 inches wide and long, and 2 inches thick.

The twigs containing leaves, flowers and fruit need to be pressed while drying in order that they may be kept in good form and made tough enough to be retained as specimens. The plants should be placed between a large supply of newspapers, or, better still, untarred building-felt, while drying. A weight of from 40 to 80 pounds is needed to produce the requisite pressure. The weight is placed upon a board covering the pile of plants and paper. On account of the size of many leaves and flower-clusters, these pressed specimens of trees should not be shorter than from 12 to 15 inches, and even a length of 18 inches is an advantage. The pads or newspapers should be about 12 by 18 inches. A transfer of the plants into dry pads each day for a few days will hasten the drying and increase the beauty of the specimens. The specimens of twigs can be mounted on cardboard by being partly pasted and partly secured by narrow strips of gummed cloth placed across the heavier portions. The cardboard should be uniform in size. One of the regular sizes of Bristol-board is 22 by 28 inches; this will cut into four pieces 11 by 14. Specimens not over 15 inches in length can readily be mounted on these, and for most collectors this might be a very convenient size. Another regular size is 22 by 32 inches, cutting well into pieces 11 by 16. Specimens 15 to 18 inches long can be mounted on these.

Some kinds of Evergreens, the Spruces especially, tend to shed their leaves after pressing. Such kinds can in most cases be made to form good specimens without pressing. Fasten the fresh specimens on pillars of plaster in boxes or frames 2 to 3 inches deep, so that they touch nothing but the column of plaster. Mix calcined plaster in water (as plasterers do), and build up a column high enough to support the branch. Place the specimen on the top of the pillar already formed, and pour over the whole some quite thin plaster till a rounded top is formed completely fastening the specimen. If the leaves are not touched at all, after they are dry, they will hang on for a long time, making specimens that will show the tree characteristics better than pressed specimens possibly could.

Chapter VII.
Figures to be used in Botanical Description.

PART II.
PLAN AND MODELS FOR TREE DESCRIPTION

All pupils should be required to write some form of composition on the trees of the region. As far as possible, these compositions should be the result of personal investigation. It is not what a pupil can read and redescribe in more or less his own words, but how accurately he can see and, from the information conveyed by his own senses, describe in his own way the things he has observed, that makes the use of such a book as this important as an educational aid. Some information in regard to trees, in a finished description, must be obtained from books, such as hardiness, geographical distribution, etc. Pupils generally should be required to include only those things which they can give from actual observation.

There are four distinct forms of tree descriptions that might be recognized by the teacher and occasionally called for as work from the pupil. 1st. A bare skeleton description, written by aid of a topical outline, from the observation of a single tree and its parts. 2d. A connected description, conveying as many facts given in the outline as can well be brought into good English sentences. This again is the description of a single tree. 3d. A connected, readable description of a certain kind of tree, made up from the observation of many trees of the same species to be found in the neighborhood. 4th. The third description including information to be obtained from outside sources in regard to the origin, geographical distribution, hardiness, character of wood, habits, durability, etc. These four plans of description are more or less successive methods to be introduced as the work of a class. Pupils should be induced to carry on their own investigations as far as possible before going to printed sources for information. A good part of class work should be devoted to the first three of the methods given, but the work might finally include the fourth form of composition. The first two methods should follow each other with each of the trees studied; that is, one week let a mere outline be written, to be followed the next week with as clear and connected a description as the ability of the pupil will allow, and containing as much of the information given in the outline as possible.

Outline for Tree Description.

The tree as a whole: size, general form, trunk, branching, twigs, character of bark, color of bark on trunk, branches, and fine spray.

Leaves: parts, arrangement, kinds, size, thickness, form, edges, veining, color, surface, duration.

Buds: position, size, form, covering, number, color.

Sap and juice.

Flowers: size, shape, color, parts, odor, position, time of blooming, duration.

Fruit: size, kind, form, color when young and when ripe, time of ripening, substance, seeds, duration, usefulness.

Wood (often necessarily omitted): hardness, weight, color, grain, markings, durability.

Remarks: the peculiarities not brought out by the above outline.

Notes on the Foregoing Outline.

The height of a tree can be readily determined by the following plan. Measure the height you can easily reach from the ground in feet and inches. Step to the trunk of the tree you wish to measure and, reaching up to this height, pin a piece of white paper on the tree. Step back a distance equal to three or four times the height of the tree; hold a lead-pencil upright between the thumb and forefinger at arm's-length. Fix it so that the end of the pencil shall be in line with the paper on the trunk; move the thumb down the pencil till it is in line with the ground at the base of the tree; move the arm and pencil upward till the thumb is in line with the paper, and note where the end of the pencil comes on the tree. Again move the pencil till the thumb is in line with the new position, and so continue the process till the top of the tree is reached. The number of the measures multiplied by the height you can reach will give quite accurately the height of the tree.

The width of the tree can be determined in the same manner, the pencil, however, being held horizontally.

In giving the forms of trees, it is well to accompany the description with a penciled outline.

The distance from the ground at which the trunk begins to branch and the extent of the branching should be noted. The direction taken by the branches, as well as the regularity and the irregularity of their position, should also be observed and described.

Although most twigs are cylindrical, still there are enough exceptions to make it necessary to examine them with reference to their form.

Under leaves, it will be well to make drawings, both of the outline and of the veining.

Crushed leaves will give the odor, and the sap can best be noticed at the bases of young leaves. The differences in sap and juice need the following words for their description: watery, milky, mucilaginous, aromatic, spicy, sweet, gummy, resinous.

Pupils should not always be expected to find out much about the flowers of a tree, as they are frequently very evanescent, and usually difficult to reach.

The fruit lasts a greater length of time and, usually dropping spontaneously, gives a much better chance for investigation.

Specimens of most of the common woods may be obtained from cabinet-makers and carpenters. In cases where these specimens are at hand, description of the wood should be required. If the school has such specimens as are described in Chapter VI., Part I., the wood in all its peculiarities can be described.

Examples of Tree Description.

Taxodium distichum (Bald Cypress).

(Atterbury's Meadow.)

No. 1.

Tree eighty-four feet tall, thirty feet wide near base, ovate, conical, pointed; trunk seven feet in circumference near base and ridged lengthwise, but only four feet at the height of six feet from the ground, where it becomes round or nearly so, then gradually tapering to the top; branches small, very numerous, beginning six feet from the ground, sloping upward from the trunk at an angle of nearly forty-five degrees; twigs very slender, numerous, pendulous, two, three or even more growing together from supernumerary buds around the old scars; bark brownish, quite rough, thick and soft on the trunk, smoother on the branches, greenish on the young spray.

Leaves about sessile, without stipules, alternate, crowded, two-ranked, thin, linear, entire, parallel-veined, with midrib, dark green, smooth, deciduous.

Buds show in the axils of only a few of the leaves, and are very small; but there are several supernumerary buds around many of the clusters of the shoots of the year.

Sap clear and slightly sticky with resin.

Flowers looked for, but not seen; must have been small, or have bloomed before my examination in the spring.

Fruit one inch in diameter, cone globular, brown in the autumn; did not notice it before; fifteen six-sided scales, two seeds under each, still hanging on, though the leaves have dropped; only to produce seeds, I think.

The wood I do not know about.

Remarks. Around the base, at some distance from the trunk, there are four peculiar knobs, seemingly coming from the roots, one being nearly a foot high and nine inches through.

No. 2.

The Bald Cypress standing near a small ditch in Atterbury's meadow is a very beautiful, tall, conical tree, over 80 feet high, with an excurrent trunk which is very large and ridged near the ground. It tapers rapidly upward, so that the circumference is only about half as great at the height of 6 feet, where the branches begin. The branches are very numerous and, considering the size of the trunk, very small; the largest of them being only about 2 inches through. They all slope upward rapidly, but the tip and fine spray show a tendency to droop; the fine thread-like branchlets, bearing the leaves of the year, are almost all pendulous.

The bark is very rough, thick and soft, as I found in pinning on the bit of paper to measure the height of the tree, when I could easily press the pin in to its head.

The leaves are very small and delicate, and as they extend out in two ranks from the thread-like twigs, look much like fine ferns. The small linear leaves and the spray drop off together in the autumn, as I can find much of last year's foliage on the ground still fastened to the twigs. I could not see any flowers, though I looked from early in the spring till the middle of the summer; then I saw a few of the globular green cones, almost an inch in diameter, showing that it had bloomed. Next spring I shall begin to look for the blossoms before the leaves come out.

On the ground, about 6 feet from the tree, there are four very strange knobs which I did not notice till I stumbled over one of them. They seem to grow from the roots, and are quite soft and reddish in color.

No. 3.

I have found twenty-two Bald Cypresses in Trenton; they are all beautiful conical trees, and seem to grow well in almost any soil, as I have found some in very wet places and some in dry, sandy soil. They look from their position as though they had been planted out, and as I have found none in the woods around the town, they are probably not native in this region. They are from 50 to nearly 100 feet tall. I found one 96 feet high. They are all of a very symmetrical, conical form, and pointed at the top; in no case has the trunk divided into branches, and on the old trees the trunk enlarges curiously near the ground, the lower portion being very rough with ridges. The bark is very thick and rough, and is so soft that a pin can readily be pushed through it to the wood. The branches are very numerous and small, and are not regularly arranged in whorls like most of the narrow-leaved trees. These branches all slope upward from the trunk, the ends having a tendency to bend downward and make delicate drooping spray, with very small, linear, entire leaves only ½ inch long. Four of the largest trees show fruit, and each of these has only about a half-dozen of the globular cones. Only a few of the trees—those in the wettest places—have the knobs on the ground near the base.

No. 4.

The Bald Cypress (Taxodium distichum) is a common tree, a native of the Gulf States, growing very abundantly in the wettest swamps of that region. The northern limit of the tree in its wild state is said to be central Delaware and southern Illinois, but it can be successfully cultivated in the region around Boston. There are several named varieties, one with the leaves but slightly spreading from the spray, and the whole of the branches showing a decided weeping tendency, so that it is called the Weeping Cypress. The knobs from the roots, called Cypress-knees, grow very abundantly around all the trees in the southern swamps. These grow to the height of from 2 to 4 feet, and are very thick, sometimes as much as 5 feet. They are hollow, and are occasionally used for bee-hives.

It is said to be a broad, flat-topped tree, spreading its top over other trees. This seems very strange, as none of those in Trenton, N. J., show such a tendency, but are quite spire-shaped. The wood is light, soft, straight-grained, and is said to be excellent for shingles and for other purposes. It generally has a dark reddish or brownish hue. It is a large tree, growing to the height of 140 feet. The trunk is sometimes 12 feet through near the ground. The flowers of the tree are in small catkins, blooming before the leaves expand in the early spring; in February, in South Carolina.

PART III.
KEY, CLASSIFICATION AND DESCRIPTION OF THE SPECIES.

Method of Using the Key.

First read all the statements following the stars (*) at the beginning of the Key; decide which one of the statements best suits the specimen you have. At the end of the chosen one there is a letter in parenthesis ( ). Somewhere below, this letter is used two or more times. Read carefully all the statements following this letter; at the end of the one which most nearly states the facts about your specimen, you will again be directed by a letter to another part of the Key. Continue this process till, instead of a letter, there is a number and name. The name is that of the genus, and forms the first part of the scientific name of the plant. Turn to the descriptive part of the book, where this number, in regular order, is found. Here descriptions of the species of the genus are given. If there are many species, another Key will lead to the species. While the illustrations are intended to represent characteristic specimens, too much dependence must not be placed upon them; the leaves even of the same plant vary considerably, and the different varieties, especially of a cultivated plant, vary widely. Read the whole description before deciding.

The fractions beside the figures indicate the scale of the drawing as compared with the natural size of the part: 1/1 indicates natural size; 2/1, that the drawing is twice the length of the object; ¼, that the drawing is one fourth the length of the object, etc.

In the description of leaves the dimensions given refer to the blade.

KEY TO THE GENERA OF TREES.