View photos of the edible plant Carya ovata (Shagbark hickory) profiled in the Wild Edible Series: Alabama, Arkansas, Kansas, Louisiana, Missouri, Oklahoma, Tennessee, and Texas: Vol 1.

A passage from Wild Edible Plants of Arkansas:

Place the de–hulled nuts in a bucket of water. Discard the
nuts that float (this usually means they’re insect damaged). Remove the submerged nuts and keep them in a dry place.

A passage from Wild Edible Plants of Kansas:

All species of Carya technically have edible nuts, BUT some species are better tasting than others. Shagbark
hickory (Carya ovata) is considered the best tasting;

View photos of the edible plant Carya illinoinensis (Pecan), profiled in the Wild Edible Series: Alabama, Louisiana, Missouri, Oklahoma, Tennessee, and Texas: Vol 1.

A passage from Wild Edible Plants of Oklahoma:

What makes Pecan a more popular nut than Hickory, is not necessarily its taste, but rather its thin shell. Pecan
is easier to de–hull and its nut meat to shell ratio is greater than that of Hickory’s.

A passage from Wild Edible Plants of Texas (Volume 1):

If encountered in the fall (even if the nuts have recently fallen to the ground) de–hull, shell, eat, and repeat!
It’s a delicious nut, a Texas native, and worthy of high praise.

View photos of the edible plant, Carya tomentosa (Mockernut hickory), profiled in the Wild Edible Series: Alabama, Arkansas, Kansas, Missouri, Louisiana, Oklahoma, and Texas: Vol 1. 

A passage from Wild Edible Plants of Arkansas:

All species of Carya technically have edible nuts, but some species are better tasting than others. Shagbark hickory (Carya ovata) is considered the best tasting; Mockernut hickory (C. tomentosa), good–tasting, but small; Bitternut hickory (C. cordiformis), poor tasting.

A passage from Wild Edible Plants of Oklahoma:

Place the de–hulled nuts in a bucket of water. Discard
the nuts that float (this usually means they’re insect damaged). Remove the submerged nuts and keep them in a dry place.