[Illustration:  FIG. 69.—­Bud of the Mockernut Hickory.]

The bitternut (Hicoria minima) can be told from the mockernut and other species of hickory by its bud, which has no scales at all.  The color of its bud is a characteristic orange yellow.  The bark is of a lighter shade than the bark of the mockernut hickory and the leaflets are more numerous than in any of the hickories, varying from 7 to 11.  Its nuts are bitter.

BLACK WALNUT (Juglans nigra)

Distinguishing characters:  By cutting a twig lengthwise, it will be seen
    that its pith is divided into little chambers as shown in Fig.
    71.  The bud is dark gray and satiny.  The bark is dark brown and
    deeply ridged and the fruit is the familiar round walnut.

[Illustration:  FIG. 70.—­Bark of the Mockernut Hickory.]

Form and size:  A tall tree with a spreading crown composed of stout
    branches.  In the open it grows very symmetrically.

Range:  Eastern United States.

Soil and location:  The black walnut prefers a deep, rich, fertile soil
    and requires a great deal of light.

Enemies:  The tree is a favorite of many caterpillars.

Value for planting:  It forms a beautiful spreading tree on open ground,
    but is not planted to any extent because it is hard to transplant. 
    It grows slowly unless the soil is very deep and rich, develops its
    leaves late in the spring and sheds them early in the fall and
    produces its fruit in great profusion.

Commercial value:  The wood is heavy, strong, of chocolate brown color
    and capable of taking a fine polish.  It is used for cabinet making
    and interior finish of houses.  The older the tree, usually, the
    better the wood, and the consumption of the species in the past has
    been so heavy that it is becoming rare.  The European varieties which
    are frequently planted in America as substitutes for the native
    species yield better nuts, but the American species produces better
    wood.

[Illustration:  FIG. 71.—­Twig of the Black Walnut.  Note the large chambers in the pith.]

[Illustration:  FIG. 72.—­Twig of the Butternut.  Note the small chambers in the pith.]

Other characters:  The fruit is a large round nut about two inches in
    diameter, covered with a smooth husk which at first is dull green
    in color and later turns brown.  The husk does not separate into
    sections.  The kernel is edible and produces an oil of commercial
    value.

    The leaves are compound and alternate with 15 to 23 leaflets to
    each.