Rhysocaryon), is a large shrub or small tree (10–30 ft tall) which grows wild along streams and ravines in Texas, New Mexico, Oklahoma, and Kansas, and the northernmost states of Mexico.

The pinnately compound leaves bear 7—25 untoothed to finely-toothed leaflets, each 1/4—1/2 in wide.

It is found at elevations ranging from 700 ft to 6700 ft.[3] Two varieties are recognized: J. microcarpa var.

Where the range of J. microcarpa overlaps with J. major, the two species interbreed, producing populations with intermediate characteristics.

[4] Juglans (literally "Jupiter's acorn") is the Latin name of the walnut.