Plants rhizomatous, rhizomes short, stout, scaly. Culms 50-240 cm
tall, 1.5-4.5 mm thick, erect; internodes glabrous. Sheaths glabrous
or sparsely hispid; ligules 2-6 mm, usually with thick, pointed auricles;
blades 10-70 cm long, 1-4 mm wide, usually glabrous. Panicles 20-75
cm, loosely contracted, yellowish to brownish; branches often flexible.
Spikelets 5-8.7 mm. Calluses blunt, villous; lower glumes
5-8 mm, pubescent, 7-9-veined; upper glumes 5-8 mm, 5-veined; awns
10-22(30) mm, about 2-3 times longer than the spikelets, once-geniculate; anthers
(2)3-5 mm. Caryopses 2-3 mm. Pedicels 3-6 mm, flexible. 2n
= 20, 40, 80.
Sorghastrum nutans grows in a wide range of habitats, from prairies to
woodlands, savannahs, and scrubland vegetation. It is native from Canada to Mexico,
and was one of the four principal grasses of the tallgrass prairie that occupied
the central United States prior to agricultural development of the region. It
is frequently used for forage, for erosion control on slopes and along highways,
and in restoration work. It is an attractive plant and can be used to advantage
in flower arrangements. It grows readily from seed if adequate moisture is available.
There are several cultivars on the market.
Culms 1-2.5 m, in loose tufts from short rhizomes, smooth except the sericeous nodes; sheaths glabrous to hirsute; ligule well developed, firm, continuous with the auricles; blades 5-10 mm wide; panicle 1-3 dm, narrow, freely branched, golden, the nodes and smaller branches ±villous; spikelets lanceolate, 6-8 mm, the first glume pale brown, villous; awn 9-15 mm, twisted below, bent at about a third of its length; sterile pedicels densely villous, 4-5.5 mm; 2n=20, 40, 80. Moist or dry prairies, open woods, and fields; throughout our range, s. to the Gulf, w. to Utah and Ariz. (S. avenaceum) An important constituent of the tall-grass prairies.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.