Aquatic and Wetland Vascular Plants of the Northern Great Plains
62. Cyperaceae, the Sedge Family
2. Carex L. -- Sedge
22. Carex gravida Bailey -- Heavy sedge
Tufted from stout rootstocks; culms erect or leaning, sharply trigonous,
3-11 dm long, roughened above. Leaves 3-8 mm wide; sheaths whitish
and conspicuously septate-nodulose dorsally, white-hyaline ventrally, not cross-rugulose.
Spikes bisexual, androgynous, single at each node, usually less than
10, in dense, ovoid to oblong heads 1-3.5 cm long; bracts usually inconspicuous,
setaceous, seldom exceeding the head; pistillate scales green to brown,
acuminate to cuspidate, shorter than the perigynia. Perigynia conspicuous
in the head, not hidden by the scales, green and pale to yellowish-brown, shiny,
plano-convex, ovate, 4-5 mm long, ca. 1/2 as wide, obscurely nerved dorsally,
nerveless ventrally, contracted to the serrulate, bidentate beak which is ca.
1/3 the total length of the perigynium; achenes lenticular, 1.8-2.2 mm
long, about as wide; stigmas 2, the style base enlarged. Jun--Jul. Wet
meadows, stream banks, floodplains and prairie swales, but more often in moist
woods and thickets; frequent; (Ont. to MT, s to OH, KY, TX and CO).