How to tell these three from each other.  If the bud is large—­an inch to
    an inch and a half long—­dark brown, and sticky, it is a
    horsechestnut.

    If the bud is not sticky, much smaller, and rusty brown to black
    in color, and the ultimate twigs, of an olive green color, are
    flattened at points below the buds, it is an ash.

[Illustration:  FIG. 19.—­Alternate Branching (Beech.)]

If it is not a horsechestnut nor an ash and its small buds have many scales covering them, the specimen with branches and buds opposite must then be a maple.  Each of the maples has one character which distinguishes it from all the other maples.  For the sugar maple, this distinguishing character is the sharp point of the bud.  For the silver maple it is the bend in the terminal twig.  For the red maple it is the smooth gray-colored bark.  For the Norway maple it is the reddish brown color of the full, round bud, and for the box elder it is the greenish color of its terminal twig.

The form of the tree and the leaves are also characteristic in each of the maples, but for the beginner who does not wish to be burdened with too many of these facts at one time, those just enumerated will be found most certain and most easily followed.

[Illustration:  FIG. 20.—­Opposite Branching (Horsechestnut.)]

THE HORSECHESTNUT (Aesculus hippocastanum)

Distinguishing characters:  The sticky nature of the terminal bud and
    its large size (about an inch long).  The bud is 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.