Carya glabra

The pignut hickory tree is a large pecan hickory and is member of the walnut or Juglandaceae family and is native to much of the eastern United States, but particularly the Appalachian forests of Kentucky and West Virginia, the Cumberland Mountains of Tennessee and the Ohio River Valley. It is a large tree and can reach over 25 m in height.

• Leaves are compound, odd-pinnate, from 15–30 cm long, with 5–7 toothed, ovate-lanceolate leaflets, each 8–15 cm long; leaves turn yellow in the fall.
• The species is monoecious. Male (staminate) flowers are in yellow-green hanging catkins typically in pairs of 2 or 3, up to 8 cm long; female (pistillate) flowers are small and yellowish-green, on short spikes, blooming in April-May.
• Fruit is a round (edible to some animals) nut (a drupe) up to 2–3 cm across, usually hanging in clusters, each nut enclosed in a green, 4-valved ridged husk. Husks split when the nuts are ripe.
• Gray bark develops scaly ridges as it matures.