The fruit is a very bitter nut, 2–3 cm (3⁄4–1+1⁄4 in) long with a green four-valved cover which splits off at maturity in the fall, and a hard, bony shell.

It is closely related to the pecan, sharing similar leaf shape and being classified in the same section of the genus Carya sect.

Bitternut hickory grows throughout the eastern United States from southwestern New Hampshire, Vermont, Maine, and southern Quebec; west to southern Ontario, central Michigan, and northern Minnesota; south to eastern Texas; and east to northwestern Florida and Georgia.

Because bitternut hickory wood is hard and durable, it is used for furniture, paneling, dowels, tool handles and ladders.

The tannins which give the nuts of bitternut hickory their bitter flavour are not fat soluble.

The pecan variety 'Major' has bitternut alleles at two simple sequence repeat loci indicating a cryptic cross that may also have involved C. ovata.