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

scirpe de Torrey, Torrey's bulrush, Torrey's club-bulrush, Torrey's three-square bulrush

Habit Plants mat-forming; rhizomes 1–3 mm diam.
Rhizomes

3–10 mm diam.

Culms

cylindric, 0.5–3 m × 2–10 mm.

sharply trigonous, sides concave distally, 0.4–1.5 m × 1.5–5 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.

4–7, nearly equaling culm;

sheath fronts delicately pinnate-fibrillose;

blades 3–6, erect, the distal mostly longer than sheath, 1–2 mm, wide, proximally thickly V-shaped central region trigonous-channeled to laterally flattened, apically asymmetically laterally flattened-trigonous;

apex often markedly eccentric, glabrous, smooth or angles papillose.

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 1 spikelet;

proximal bract erect, resembling leaf blade, 3–20 cm.

Spikelets

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.

1–4, 7–18 × 3–5 mm;

scales straw-colored to orange-brown or central region greenish, ovate-lanceolate, 4–5 × 2.5 mm, margins entire, smooth or awn sparsely spinulose, sometimes distally ciliolate at 40X, apex acute, mucronate, mucro 0.2–0.5 mm.

Flowers

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

anthers 2 mm;

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

perianth members 6, brown, bristlelike, equaling to slightly exceeding achene, spinulose;

anthers 2–3 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.

brown, compressed trigonous, ovoid to obovoid, 3.5–4.5 × 1.7–2 mm;

beak 0.5–1 mm.

2n

= 42.

= 70.

Schoenoplectus tabernaemontani

Schoenoplectus torreyi

Phenology Fruiting late spring–summer, spring–winter (south). Fruiting summer.
Habitat Fresh to brackish marshes, fens, bogs, lakes, stream banks and bars, pioneering in disturbed places, often emergent in water to 1 m Emergent in fresh ponds and marshes, often with fluctuating water levels
Elevation 0–2400 m (0–7900 ft) 10–200 m (0–700 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
CT; DE; IA; IL; IN; KY; MA; ME; MI; MN; MO; NH; NJ; NY; OH; PA; RI; VA; VT; WI; MB; NB; ON; QC
[WildflowerSearch map]
[BONAP county 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.)

Schoenoplectus torreyi is very locally distributed, and probably has been extirpated from many historic localities. A specimen from an uncertain locality in Kentucky was collected in 1830. I have not seen specimens from North Dakota, South Dakota, or Nebraska. Scirpus torreyi was placed in synonymy under S. subterminalis Torrey var. cylindricus (Torrey) T. Koyama [misapplied, = Bolboschoenus novae-angliae by T. Koyama (1962b)].

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

Source FNA vol. 23, p. 47. FNA vol. 23, p. 54.
Parent taxa Cyperaceae > Schoenoplectus > sect. Schoenoplectus Cyperaceae > Schoenoplectus > sect. Malacogeton
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. saximontanus, S. smithii, S. subterminalis, S. tabernaemontani, S. triqueter
Synonyms Scirpus tabernaemontani, Scirpus lacustris subsp. glaucus, Scirpus lacustris subsp. validus, Scirpus lacustris var. tabernaemontani, Scirpus validus, Scirpus validus var. creber Scirpus torreyi
Name authority (C. C. Gmelin) Palla: Verh. K. K. Zool.-Bot. Ges. Wien 38(Sitzungsber.): 49. (1888) (Olney) Palla: Allg. Bot. Z. Syst. 17(Beil.): 3. (1912)
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