Studies of Trees | Page 8

dark brown in color. See Fig. 20.
Leaf: Five to seven leaflets, usually seven. Fig. 21.
Form and size: Medium-sized tree, pyramidal head and coarse twigs.
Range: Europe and eastern United States.
Soil and location: Prefers a deep, rich soil.

Enemies: The leaves are the favorite food of caterpillars and are subject to a blight which
turns them brown prematurely. The trunk is often attacked by a disease which causes the
flow of a slimy substance.
Value for planting: On account of its showy flowers, the horsechestnut is a favorite for
the park and lawn.
Commercial value: The wood is not durable and is not used commercially.
Other characters: The flowers appear in large white clusters in May and June. The fruit is
large, round, and prickly.
[Illustration: FIG. 21.--Leaf of the Horsechestnut.]
Comparisons: The red horsechestnut differs from this tree in having red flowers. The
buckeye is similar to the horsechestnut, but its bud is not sticky and is of a lighter gray
color, while the leaf generally has only five leaflets.
THE WHITE ASH (Fraxinus americana)
Distinguishing characters: The terminal *twigs* of glossy olive green color are
*flattened* below the bud. Fig. 22. The bud is rusty-brown.
[Illustration: FIG. 22.--Twig of White Ash.]
Leaf: Five to nine leaflets. Fig. 23.
Form and size: A large tree with a straight trunk.
Range: Eastern North America.
Soil and location: Rich, moist soil.
Enemies: In cities it is very often attacked by sucking insects.
Value for planting: The white ash grows rapidly. On account of its insect enemies in
cities, it should be used more for forest planting and only occasionally for ornament.
Commercial value: It has a heavy, tough, and strong wood, which is valuable in the
manufacture of cooperage stock, agricultural implements, and carriages. It is superior in
value to the black ash.
Other characters: The bark is gray. The flowers appear in May.
Comparisons: The white ash is apt to be confused with the black ash (Fraxinus nigra),
but differs from the latter in having a lighter-colored bud. The bud of the black ash is
black. The bark of the white ash is darker in color and the terminal twigs are more
flattened than those of the black ash.

[Illustration: FIG. 23.--Leaf of White Ash.]
SUGAR MAPLE (Acer saccharum)
Distinguishing characters: The *bud is sharp-pointed*, scaly, and reddish brown. Fig. 24.
[Illustration: FIG. 24.--Twig of the Sugar Maple.]
Leaf: Has sharp points and round sinus. Fig. 25.
Form and size: The crown is oval when the tree is young and round in old age. Fig. 26.
Range: Eastern United States.
Soil and location: Moist and deep soil, and cool, shady positions.
Enemies: Subject to drouth, especially in cities. Is attacked by the sugar maple borer and
the maple phenacoccus, a sucking insect.
Value for planting: Its rich and yellow color in the fall, and the fine spread of its crown
make it a desirable tree for the lawn, especially in the country.
Commercial value: Its wood is hard and takes a good polish; used for interior finish and
furniture. The tree is also the source of maple sugar. Fig. 27.
Other characters: The bark is smooth in young trees and in old trees it shags in large
plates. The flowers appear in the early part of April.
Other common names: The sugar maple is sometimes called rock maple or hard maple.
SILVER MAPLE (Acer saccharinum)
Distinguishing characters: The tips of the *twigs curve upwards* (Fig. 28), the bark is
scaly, and the leaves are very deeply cleft and are silvery on the under side.
[Illustration: FIG. 25.--Leaf of Sugar Maple.]
Leaf: Deeply cleft and silvery under side. Fig. 29.
Form and size: A large tree with the main branches separating from the trunk a few feet
from the ground. The terminal twigs are long, slender, and drooping.
Range: Eastern United States.
Soil and location: Moist places.
Enemies: The leopard moth, a wood-boring insect, and the cottony-maple scale, a
sucking insect.

[Illustration: FIG. 26.--The Sugar Maple.]
Value for planting: Grows too rapidly and is too short-lived to be durable.
Commercial value: Its wood is soft, weak, and little used.
Other characters: The bark is light gray, smooth at first and scaly later on. The scales are
free at each end and attached in the center. The flowers appear before the leaves in the
latter part of March or early April.
[Illustration: FIG. 27.--Tapping the Sugar Maple.]
Other common names: The silver maple is sometimes known as soft maple or white
maple.
RED MAPLE (Acer rubrum)
[Illustration: FIG. 28.--Terminal Twig of Silver Maple.]
Distinguishing characters: The *bark is smooth and light gray*, like that of the beech, on
the upper branches in older trees, and in young trees over the whole trunk. Fig. 30. The
buds are in clusters, and the terminal twigs,