Plants in small clumps, with rhizomes 3-5 mm thick. Basal
rosettes well-differentiated; blades sometimes more than 10 cm, lanceolate.
Culms 50-150 cm, usually robust, erect; nodes often swollen, densely
bearded with thin retrorse hairs above a constricted, glabrous, viscid ring;
internodes grayish-purple, velvety-pubescent; fall phase branching
from the mid- and upper culm nodes, with long, repeatedly forking and often
recurving branches, ultimately with fascicles of reduced blades and included
secondary panicles. Cauline leaves 7-11; sheaths not overlapping,
narrowing distally, lustrous, bases sparsely to densely retrorsely villous,
hairs papillose-based, summits purplish, with yellowish spots; collars
densely villous; ligules 0.5-2 mm, of hairs; blades 9-20 cm long,
9-20 mm wide, thick, densely soft pubescent, bases rounded to subcordate, margins
ciliate basally. Primary panicles 6-16 cm long, 5-12 cm wide, well-exserted,
dense; rachises softly pubescent basally; branches often mottled
with purplish viscid spots, glabrous. Spikelets 2.2-2.8 mm long, 1.3-1.5
mm wide, ovoid-ellipsoid, often purplish basally, prominently veined, margins
and apices sparsely to densely pubescent, hairs papillose-based. Lower glumes
0.6-1.3 mm, subtruncate to acuminate; lower florets sterile; upper
florets minutely apiculate. 2n = 18.
Dichanthelium scoparium grows in moist, sandy, open, often disturbed
areas of the southeastern United States. It is also present in the West Indies.
The primary panicles are open-pollinated, produced from May to early August;
the secondary panicles are cleistogamous and are produced from July through
October.
Panicum glutinoscabrum Fernald may represent rare putative
hybrids of Dichanthelium scoparium with D.
acuminatum, and P. mundum Fernald, rare hybrids with D. dichotomum.
Culms solitary or few, erect or geniculate at base, tall and stout, 7-15 dm, with a broad viscid-glabrous band just below the nodes, otherwise softly long-spreading- hairy and with bearded nodes; sheaths loose, often constricted at the summit, densely reflexed-villous at base, softly hairy distally except along the middle of the back, where glabrous and viscid; blades lanceolate, the larger 10-25 cm נ10-20 mm, slightly narrowed to the rounded base, softly hairy on both sides; primary panicle ovoid, many-fld, 8-15 cm, softly hairy, glandular-spotted; spikelets soft-hairy, obovoid, abruptly apiculate, 2-2.7 mm; first glume two-fifths as long, triangular-ovate, acute; second glume slightly shorter than the fr and sterile lemma; autumnal phase copiously branched and rebranched from the middle and upper nodes, the blades progressively reduced and the uppermost often with the sheaths hairy throughout, the panicles small, few-fld, usually shorter than the blades; 2n=18. Wet soil; Cuba and Fla. to Tex., n. to Mo., Ky., N.C., and along the coastal plain to Mass. (Dichanthelium s.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.