Stems erect, to 15 dm, variously hairy; principal petioles mostly 5-20 mm; lfls oval or elliptic to somewhat ovate or obovate, 1.5-4 cm, half to three-fourths as wide, variously hairy, or glabrous above; spikes numerous, short-cylindric, 1-3 cm, usually on peduncles equaling or surpassing the subtending lvs; fls ochroleucous, 6-9 mm; cal-lobes densely hairy, 3.5-7 mm; fr elliptic, pointed at both ends, about as long as the cal; 2n=20. Abundant in dry soil; Me. to Fla., w. to Wis., Ill., Mo., Okla., and Tex. Late summer. Two vars.: var. hirta, with the upper surface of the lfls glabrous, strigose, or pilose, but not silvery, and with the stems villous to pilose, has nearly the range of the sp., but is rare within the range of var. curtissii. Var. curtissii (Clewell) Cronquist, with the lfls densely silvery-strigillose and the stems appressed-hairy or densely short-pilose, occurs on the s. coastal plain from s. Va. to Fla. and Ala.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.