Scirpus divaricatus Elliot
Family: Cyperaceae
Spreading Bulrush
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Plants cespitose; rhizomes not apparent. Culms: fertile ones lax, reclining, inflorescences lopping over to (or nearly to) ground; nodes frequently with axillary bulblets. Leaves 10-18 per culm; proximal leaf sheaths green or brownish; proximal sheaths and blades with septa few, inconspicuous; blades 16-55 cm × 4-8 mm. Inflorescences terminal; rays divergent, proximal rays smooth, pedicels and distal rays scabrous, rays often bearing axillary bulblets; bases of involucral bracts green or brownish, not glutinous. Spikelets in open cymes, central spikelet of each cyme sessile, others long-pedicellate, spikelets cylindric to narrowly ovoid, 4-14 × 1-2 mm; scales light brown to reddish with broad green midribs, broadly ovate or elliptic, 1.2-1.8 mm, apex rounded to obtuse, apiculate, or sometimes short-mucronate, apiculus or mucro (if present) to 0.1 mm. Flowers: perianth bristles persistent, 6, stout, contorted, equaling or longer than achene, not projecting beyond it, with delicate, round-tipped, retrorse teeth in distal 1/2, enclosed within scales; styles 3-fid. Achenes off-white to yellowish brown, elliptic-obovate in outline, strongly trigonous with very strong angles and concave sides, 0.8-1 × 0.6-0.8 mm. 2n = 28.

Fruiting late spring-early summer (May-Jun). Lowland swamps along streams (often associated with Taxodium); 0-100 m; Ala., Ark., Fla., Ga., La., Mo., N.C., S.C., Tenn., Tex., Va.

The inflorescence of Scirpus divaricatus is very large and open. As in related species, the central spikelet of each cyme is sessile, and the others are long-pedicellate. The cymes often consist of only two spikelets in which the sessile, terminal spikelet may appear lateral.

Cespitose perennial; stems slender and weak, to 1.5 m, often lopping over to the ground, often with bulblets at the nodes; lvs 10-20, mostly 5-10 mm wide; infl large and lax, often bearing tufts of lvs; spikelets cylindric, to 1 cm, individually pedicellate; scales numerous, in few rows on the rachilla, broadly ovate, with green midrib and pale or hyaline sides; bristles 6, ca equal to achene, contorted, retrorsely barbellate above the middle; achenes 1 mm, elliptic or obovate, trigonous with protruding angles and concave sides; 2n=28. Swamps and wet woods; n. Fla. to La., n. to se. Va., s. Tenn., and se. Mo. Fr May, June.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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