Juglans microcarpa Juglans microcarpa Juglans microcarpa, known also as the little walnut, Texas walnut, Texas black walnut or little black walnut (as it belongs to the "black walnuts" section "Juglans" sect. "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. It produces nuts with a width of 1/2—3/4 in. 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. Two varieties are recognized: "J. microcarpa" var. "microcarpa" and "J. microcarpa"
Castanea sativa the plant can’t pollinate itself, making cross-pollination necessary. Some cultivars only produce one large nut per cupule, while others produce up to three nuts. The nut itself is composed of two skins: an external, shiny brown part, and an internal skin adhering to the fruit. Inside, there is an edible, creamy-white part developed from the cotyledon. The tree requires a mild climate and adequate moisture for good growth and a good nut harvest. Its year-growth (but not the rest of the tree) is sensitive to late spring and early autumn frosts, and is intolerant of lime. Under forest conditions, it