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enable glossary links

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

scirpe subterminal, swaying bulrush, swaying clubrush, water annual-bulrush, water bulrush, water club-rush

Habit Plants mat-forming; rhizomes to 1 mm diam; terminal tubers sometimes present, to 3 mm thick, fleshy.
Rhizomes

3–10 mm diam.

Culms

cylindric, 0.5–3 m × 2–10 mm.

subcylindric, 0.2–1.5 m × 0.5–1 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.

3–20+, smooth;

sheath fronts sometimes delicately pinnate-fibrillose;

blades 3–20, when erect C-shaped in cross section proximally, elliptic most of length, when submerged usually flaccid and filiform to narrowly ribbonlike, probably longer than sheath, 0.2–1 mm wide.

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.

a solitary, erect spikelet;

proximal bract erect, like stiff leaf blade, 7–60 mm.

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.

5–15 × 3–7 mm;

scales pale brown, or central region green when young, ovate-lanceolate, 4–6 × 1.5 mm, smooth, margins sometimes ciliolate apically at 40X, midrib obscure, apex acute, entire, minutely mucronate.

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, from 1/2 of to equaling achene beak, spinulose;

anthers 2–3.5 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.

brown, strongly trigonous, obovoid to obpyriform, (2.5–)3–3.5 × 1.5–1.7 mm;

beak 0.3–0.8 mm.

2n

= 42.

= 72.

Schoenoplectus tabernaemontani

Schoenoplectus subterminalis

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 Submerged to emergent in water to 1 m or sometimes terrestrial, fresh lakes, streams, bogs
Elevation 0–2400 m (0–7900 ft) 10–2200 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
AK; AL; CA; CT; DE; FL; GA; ID; IL; IN; MA; MD; ME; MI; MN; MO; MT; NC; NH; NJ; NY; OH; OR; PA; RI; SC; UT; VA; VT; WA; WI; BC; NB; NL; NS; ON; PE; QC; SK
[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 subterminalis often forms lawnlike, underwater mats that are entirely vegetative or have only the inflorescences emergent. This species is probably extirpated from Illinois. Schoenoplectus subterminalis var. terrestris Paine [= S. subterminalis forma terrestris (Paine) Fernald] probably does not deserve taxonomic recognition.

(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. 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 subterminalis
Name authority (C. C. Gmelin) Palla: Verh. K. K. Zool.-Bot. Ges. Wien 38(Sitzungsber.): 49. (1888) (Torrey) Soják: Cas. Nár. Mus., Odd. Prír. 140: 127. (1972)
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