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great bulrush, scirpe des étangs, soft-stem bulrush, soft-stem club-bulrush, tule

Rocky Mountain bulrush

Habit Plants annual or perennial; rhizomes 1 mm diam.
Rhizomes

3–10 mm diam.

Culms

cylindric, 0.5–3 m × 2–10 mm.

often arching to decumbent, cylindric, ridged when dry, 0.09–0.65 m × 0.5–1.5 mm.

Leaves

3–4, basal;

sheath fronts membranous-translucent, often pinnate-fibrillose;

blades 1–2, C-shaped to dorsiventrally flat in cross section, usually much shorter than sheath, distal blade 2–200 × 1–4 mm, margins often scabridulous.

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

2–4 times branched, branches to 15(–25) cm;

proximal bract usually erect, thickly C-shaped to subterete, 1–8 cm, margins sometimes scabridulous.

capitate or of 1 spikelet or with 1 or 2 branches to 15 mm;

proximal bract erect, like leaf blades, 5–15 cm.

Spikelet(s)

15–200, solitary or in clusters of 2–4(–7), commonly all solitary, 3–17 × 2.5–4 mm;

scales uniformly dark to pale orange-brown, sometimes straw-colored, sometimes prominently lineolate-spotted, midrib often pale or green, ovate, 2–3.5 × 1.5–2 mm, sparsely (rarely densely) reddish or straw-colored, scabrous on awn and distal parts of midrib and sometimes flanks, margins ciliate, hairs contorted;

flanks veinless, apex obtuse to rounded, notch 0.2–0.3 mm deep, awn straight or bent, 0.2–0.8 mm.

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.

Flowers

perianth bristles 6, brown, ± equaling achene, densely retrorsely spinulose;

anthers 2 mm;

styles 2-fid, sometimes 3-fid near spikelet apex.

perianth absent;

anthers 0.3–0.5 mm;

styles 3-fid.

Achenes

dark gray-brown when ripe, plano-convex, obovoid, 1.5–2.8 × 1.2–1.7 mm;

beak 0.2–0.4 mm.

Amphicarpic

achenes trigonous, 2.2–3 mm including stout, tapered beak 0.3 mm, with many obscure to evident horizontal ridges.

2n

= 42.

= 50.

Schoenoplectus tabernaemontani

Schoenoplectus saximontanus

Phenology Fruiting late spring–summer, spring–winter (south). Fruiting late summer–fall, spring–fall (California, Texas).
Habitat Fresh to brackish marshes, fens, bogs, lakes, stream banks and bars, pioneering in disturbed places, often emergent in water to 1 m Damp soils to emergent, freshwater ponds, ditches, often drying, disturbed, and sandy areas
Elevation 0–2400 m (0–7900 ft) 0–2200 m (0–7200 ft)
Distribution
from FNA
AK; AL; AR; AZ; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NL; NS; NT; ON; PE; QC; SK; YT; Mexico; Central America; West Indies; s South America; Eurasia; Africa; Pacific Islands; Australia; New Zealand
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; CO; IL; KS; MO; NE; OH; OK; SD; TX; UT; WY; BC; Mexico (San Luis Potosí, Tamaulipas)
[WildflowerSearch map]
Discussion

Two yellow-striped forms of Schoenoplectus tabernaemontani are grown as ornamentals.

Schoenoplectus validus, described from the Caribbean, and S. tabernaemontani, described from Europe, are here treated as one variable, cosmopolitan species without infraspecific taxa, pending further studies (J. Browning et al. 1995b; S. G. Smith 1995). Most North American plants have spikelets with reddish papillae or prickles on the scales, whereas some plants of coastal and boreal North America closely resemble most plants of northwestern Europe and southern Africa in their densely reddish prickly-papillose scales and are similar to the type of Scirpus glaucus J. E. Smith.

Schoenoplectus tabernaemontani, S. acutus, S. heterochaetus, S. lacustris, and S. triqueter belong to the very difficult S. lacustris complex. The entire complex except S. triqueter was treated as the single species Scirpus lacustris (T. Koyama 1962b). Many Old World authors treat Schoenoplectus tabernaemontani as S. lacustris var. tabernaemontani or subsp. glaucus.

Much of the local infraspecific variation in the Schoenoplectus lacustris complex is probably because of hybridization. Some studies support the recognition of separate species in this group (J. Browning et al. 1995b). Hybrids in North America include S. acutus × S. tabernaemontani, widespread and common, especially in the east; S. acutus × S. heterochaetus = S. ×oblongus (T. Koyama) Soják, widespread but uncommon; S. heterochaetus × S. tabernaemontani = S. ×steinmetzii (Fernald) S. G. Smith, eastern and most uncommon; S. tabernaemontani × S. triqueter = S. ×kuekenthalianus (Junge) Kent, lower Columbia River in Oregon and probably Washington; and S. acutus var. occidentalis × S. californicus, local in California. Except for its trigonous culms, S. triqueter is very similar to the S. lacustris complex and freely hybridizes with S. tabernaemontani, both in North America and Europe.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

The distribution of Schoenoplectus saximontanus is very scattered (local).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 23, p. 47. FNA vol. 23, p. 59.
Parent taxa Cyperaceae > Schoenoplectus > sect. Schoenoplectus Cyperaceae > Schoenoplectus > sect. Supini
Sibling taxa
S. acutus, S. americanus, S. californicus, S. deltarum, S. erectus, S. etuberculatus, S. hallii, S. heterochaetus, S. mucronatus, S. pungens, S. purshianus, S. saximontanus, S. smithii, S. subterminalis, S. torreyi, S. triqueter
S. acutus, S. americanus, S. californicus, S. deltarum, S. erectus, S. etuberculatus, S. hallii, S. heterochaetus, S. mucronatus, S. pungens, S. purshianus, S. smithii, S. subterminalis, S. tabernaemontani, S. torreyi, S. triqueter
Synonyms Scirpus tabernaemontani, Scirpus lacustris subsp. glaucus, Scirpus lacustris subsp. validus, Scirpus lacustris var. tabernaemontani, Scirpus validus, Scirpus validus var. creber Scirpus saximontanus, Scirpus bergsonii, Scirpus supinus var. saximontanus
Name authority (C. C. Gmelin) Palla: Verh. K. K. Zool.-Bot. Ges. Wien 38(Sitzungsber.): 49. (1888) (Fernald) J. Raynal: Adansonia, n. s. 16: 141. (1976)
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