Castanea pumila

Shrub to small tree with toothed leaves, usually densely hairy beneath, and smooth brown nuts borne in very prickly burs about 1 and 1/2 inches across.

Easily distinguished from C. dentata by leaves (larger and glabrous beneath in C. dentata) and fruits (larger and with more than one nut per fruit in C. dentata), although there is a hybrid, C. x neglecta. The "C. pumila complex" of the southeastern U.S. is now generally deemed to consist of only one species with 2 varieties. The currently accepted C. pumila var. pumila includes plants formerly known as C. alnifolia (C. pumila var. alnifolia), C. ashei (C. pumila var. ashei), C. floridana (C. alnifolia var. floridana), and C. margaretta. In its typical form, var. pumila is separated from var. ozarkensis by (1) pubescent branchlets (vs. smooth or only finely hairy); (2) undersides of leaves densely white-hairy (vs. minutely pubescent to glabrate beneath); (3) leaf teeth smaller, 1-3 mm long (vs. 3-8 mm long); (4) fruiting involucres 2-2.5 cm in diameter, their spines 3-7 mm long (vs. 2.3-3 cm in diameter, their spines 1-1.3 cm long); (5) habit: usually shrub, sometimes small tree (vs. more often a tree, and larger - to 20 m high). (Fernald 1950, Elias 1980) However, some of the more southern forms ("C. alnifolia" and "C. floridana") vary toward ozarkensis in degree of pubescence, size of involucre, length of spines, and overall height. Through most of the range of var. pumila, var. ozarkensis is absent, and within the latter's range, var. pumila is less common.

Typically a species of dry open woods and edges, in sandy or rocky, acid soil. (Elias 1980, Gleason & Cronquist 1991, Hightshoe 1988, Hough 1983, Radford et al. 1968) "Dry rocky slopes, dry woods, steep rocky land, rocky stream banks, sandy ridges, borders of swamps, open woods" (Hightshoe 1988). In northern Florida and adjacent regions: "longleaf pine-scrub oak sand ridges and hills that are burned frequently; similarly in open stands of planted pine on ridges and hills; less frequent in sand pine-oak scrub; in railroad rights-of-way, fence and hedge rows, old fields; local and scattered in xeric to mesic mixed woodlands" (Godfrey 1988). Soils: well to excessively drained, average to droughty in moisture, moderately to slightly acid (pH 5.1-6.5), coarse (sandy plains, sandy and gravelly loams) to fine (silty clays, sandy clays; dislikes heavy clays) (Hightshoe 1988).

Killed back to the roots by chestnut blight fungus (Cryphonectria parasitica) but resprouts, often forming clumps; intermediate in shade tolerance; resistant to heat and drought; sensitive to soil compaction; intolerant of flooding (Hightshoe 1988). Resprouts after fire and often forms extensive clones on frequently burned sites (Godfrey 1988). Apparently not all C. pumila is clonal: Radford et al. (1968) distinguished "C. alnifolia var. alnifolia" [from the southern part of the range, now included in C. pumila var. pumila] by its clonality, lacking in typical C. pumila.

Monoecious, the staminate and pistillate flowers usually in separate clusters but sometimes a few pistillate flowers at the base of an otherwise staminate cluster. The genus is largely self-sterile (Fryxell 1957, Schopmeyer 1974). Pollination is by wind in this genus. Nuts are eaten by various mammals and birds.