American chestnut: C. dentata (Marsh.) Borkh.
Chinese chestnut: C. mollissima Blume
European chestnut: C. sativa Mill.
Japanese chestnut: C. crenata Sieb. & Zucc.
Chinquapin: C. pumila (L.) Mill.
Source: Magness et al. 1971
The various chestnut species vary in height from near 100 feet for the American to not over 30 feet for the Japanese. All have elongated, oval to lanceolate entire leaves. The fruits are spined burrs, fibrous as they mature, which partially open at maturity. They contain up to 5 angular nuts. The "shell" or covering of the kernel is rather thin and tough, leathery rather than woody. A fungus disease, chestnut blight, has killed practically all large American chestnut trees in the U.S. The Chinese chestnut, resistant to the blight, is now planted somewhat, and considerable quantities of European nuts are imported.