Interesting Facts
Hickories may be divided into three groups, the pecans, the shagbarks, and the pignuts. Bitternut hickory is in the pecan group, which is distinguishable from the others by its yellow bud scales and its fruits (nuts), which have a four-winged husk. It is the fastest growing hickory and lives for 150 - 200 years. The Latin name "cordiformis" refers to the heart-shaped leaves. 

Identifying Features

Bark
The bark is brown or gray, becoming furrowed as the tree grows older.
Buds
The terminal buds are distinctive. They are slender, almost an inch long, pointed at the tip, and covered with small, bright yellow dots and fine hairs.
Leaves
The leaves are alternate and pinnately compound with 7 - 9 lance-shaped, finely-toothed leaflets, 6 inches long and 1 1/2 to 2 1/2 inches wide. The upper surface of the leaflets is smooth, shiny, and green and the underside is paler and slightly hairy. 
Flowers
Both male and female flowers are born on the same tree, but separately (moneocious). Like the other hickories, flowers appear as drooping catkins in the spring after the leaves start to unfold.
Fruits
The nuts ripen in the fall and have a thin, winged husk that splits at the seams. They are yellowish- brown, round, and approximately 1 inch in diameter. The seeds are very bitter, though squirrels, mice, and deer eat them.