Schoenoplectus saximontanus
Adansonia, n. s. 16: 141. 1976.
Plants annual or perennial; rhizomes 1 mm diam. Culms often arching to decumbent, cylindric, ridged when dry, 0.09–0.65 m × 0.5–1.5 mm. Leaves 3–4, 1(–2) cauline; sheath fronts not pinnate-fibrillose; blades 1–2, proximally thickly C-shaped in cross section, distally flat, rudimentary to longer than sheath, 1–200 × 0.2–1 mm, smooth or margins distally spinulose. Inflorescences capitate or of 1 spikelet or with 1 or 2 branches to 15 mm; proximal bract erect, like leaf blades, 5–15 cm. Spikelets 1–20; 6–20 × 3 mm; scales pale orange-brown to colorless, midrib region sometimes greenish, ovate, 2.2–3(–3.5) × 1.5 mm, awn sparsely spinulose, margins ciliolate, midrib keeled distally, apex entire, rounded, awn 0.2–0.5 mm or to 1 mm on proximal scale. Flowers: perianth absent; anthers 0.3–0.5 mm; styles 3-fid. Spikelet achenes blackish brown, nearly equilaterally sharply trigonous, ovoid to obovoid, 1.3–1.8 × 1–1.4 mm, with 10–20 mostly sharp ridges; beak 0.1 mm. Amphicarpic achenes trigonous, 2.2–3 mm including stout, tapered beak 0.3 mm, with many obscure to evident horizontal ridges. 2n = 50.
Phenology: Fruiting late summer–fall, spring–fall (California, Texas).
Habitat: Damp soils to emergent, freshwater ponds, ditches, often drying, disturbed, and sandy areas
Elevation: 0–2200 m
Distribution
B.C., Calif., Colo., Ill., Kans., Mo., Nebr., Ohio, Okla., S.Dak., Tex., Utah, Wyo., Mexico (San Luis Potosí, Tamaulipas).
Discussion
The distribution of Schoenoplectus saximontanus is very scattered (local).
Selected References
None.