Comparisons:  The butternut (Juglans cinerea) is another tree that
    has the pith divided into little chambers, but the little chambers
    here are shorter than in the black walnut, as may be seen from a
    comparison of Figs. 71 and 72.  The bark of the butternut is light
    gray while that of the black walnut is dark.  The buds in the
    butternut are longer than those of the black walnut and are light
    brown instead of gray in color.  The form of the tree is low and
    spreading as compared with the black walnut.  The fruit in the
    butternut is elongated while that of the black walnut is round.  The
    leaves of the butternut have fewer leaflets and these are lighter in
    color.

GROUP X. TULIP TREE, SWEET GUM, LINDEN, MAGNOLIA, LOCUST, CATALPA, DOGWOOD, MULBERRY AND OSAGE ORANGE

TULIP TREE (Liriodendron tulipifera)

Distinguishing characters:  There are four characters that stand out
    conspicuously in the tulip tree—­the bud, the trunk, the
    persistent fruit cups and the wedged leaf.

The bud, Fig. 74, about three-quarters of an inch long, is covered by two purplish scales which lend special significance to its whole appearance.  The trunk is extremely individual because it rises stout and shaft-like, away above the ground without a branch as shown in Fig. 73.  The tree flowers in the latter part of May but the cup that holds the fruit persists throughout the winter.  The leaf, Fig. 75, has four lobes, is nearly as broad as it is long and so notched at the upper end that it looks different from any other leaf.

[Illustration:  FIG. 73.—­The Tulip Tree.]

[Illustration:  FIG. 74.—­Bud of the Tulip Tree.]

Form and size:  The tulip tree is one of the largest, stateliest and
    tallest of our trees.

Range:  Eastern United States.

Soil and location:  Requires a deep, moist soil.

Enemies:  Comparatively free from insects and disease.

Value for planting:  The tree has great value as a specimen on the lawn
    but is undesirable as a street tree because it requires considerable
    moisture and transplants with difficulty.  It should be planted while
    young and where it can obtain plenty of light.  It grows rapidly.

Commercial value:  The wood is commercially known as whitewood and
    yellow poplar.  It is light, soft, not strong and easily worked.  It
    is used in construction, for interior finish of houses, woodenware
    and shingles.  It has a medicinal value.

Other characters:  The flower, shown in Fig. 75, is greenish yellow in
    color, appears in May and resembles a tulip; hence the name tulip
    tree.  The fruit is a cone.

Other common names:  Whitewood; yellow poplar; poplar and tulip
    poplar.