Sheaths usually glabrous, sometimes sparsely pubescent, rarely densely
pubescent. Panicles to 55.5 cm long, usually 6.7-13.9 times as long as
wide; branches to 23 cm long, erect or ascending, at least in the upper
1/3 of the panicle. Spikelets usually without a brownish cast, relatively
closely imbricate.
Calamovilfa longifolia var. longifolia is a characteristic grass
on the drier prairies of the interior plains, from southern Canada to northern
New Mexico, with reports from southern Arizona. It also grows, as an adventive,
in Washington, Wisconsin, Michigan, and Missouri.
Panicle slender, 6.5-14 times as long as wide, with crowded spikelets and ±ascending or erect branches; sheaths usually glabrous, seldom lightly pubescent, rarely densely so. Dry sandy soil and prairies from Wis. and Ill. to sw. Ont., se. B.C., Wyo., and Colo.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.