Aquatic and Wetland Vascular Plants of the Northern Great Plains
62. Cyperaceae, the Sedge Family
3. Cyperus L. -- Galingale, umbrella sedge
1. Cyperus acuminatus Torr. & Hook.
Low tufted annual 5-20 cm tall. Leaves to as long as the culms or longer,
0.5-2 mm wide; involucral bracts similar, to 3 mm wide, surpassing the
inflorescence. Spikelets crowded in 1-5 hemispheric to globose spikes,
the spikes to 1 cm long, often broader than long, one spike sessile and additional
ones borne on rays mostly 0.5-2(3) cm long; spikelets 3-7 mm long; scales
1-2 mm long, acuminate, curving outward toward the tip, pale green, becoming
tan at maturity, strongly 3-nerved, the lateral nerves resembling keels; rachilla
persistent, the scales falling separately; stamen solitary; styles trifid.
Achenes tan to pale brown, trigonous, 0.5-0.9 mm long, ca. 1/2 as wide.
Late Jul--Sep. Muddy or sandy stream banks, shores and flats; uncommon, in ND
to frequent in NE; (IN to ND, s to GA, LA and TX; also the Pacific Coast).