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enable glossary links

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

bulrush, club-rush, naked-stem bulrush, naked-stem bulrushes, schoenoplecte, scirpes

Habit Herbs, perennial or annual, cespitose or not, rhizomatous or not.
Rhizomes

3–10 mm diam.

Culms

cylindric, 0.5–3 m × 2–10 mm.

solitary or not, cylindric to strongly trigonous, smooth, glabrous, spongy with internal air cavities.

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.

basal, rarely 1(–2) cauline;

sheaths tubular;

ligules membranous, glabrous;

blades well developed to rudimentary, cross section dorsiventrally flat to C-shaped or laterally compressed, soft, smooth or margins sometimes distally scabrous or 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.

terminal, capitate to openly paniculate;

spikelets 1–100+;

involucral bracts 1–5, leaflike, proximal bract erect to spreading.

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.

terete, 3–25 × 2–5 mm;

scales deciduous, 8+, spirally arranged, each subtending flower, or proximal scale empty (sometimes called a bracteole), floral scales with apex entire or 2-fid, midrib usually prolonged into mucro or awn, smooth or abaxial surface scabrous, margins ciliate.

Flowers

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

anthers 2 mm;

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

bisexual (basal flowers pistillate in amphicarpic species);

perianth of 0–6(–8) bristles, straight or curved, spinulose, straplike, sometimes fringed with soft, blunt hairs, shorter than to somewhat exceeding achene;

stamens 3;

anthers 3 mm;

styles linear, 2–3-fid, base not or scarcely enlarged, deciduous in fruit.

Achenes

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

beak 0.2–0.4 mm.

biconvex to trigonous, with apical beak, faintly to prominently rugose or with transverse wavy ridges, 2.5–3.5 mm including 0.1–2 mm beak.

2n

= 42.

Schoenoplectus tabernaemontani

Schoenoplectus

Phenology Fruiting late spring–summer, spring–winter (south).
Habitat Fresh to brackish marshes, fens, bogs, lakes, stream banks and bars, pioneering in disturbed places, often emergent in water to 1 m
Elevation 0–2400 m (0–7900 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 USDA
Worldwide
[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.)

Species ca. 77 (17 in the flora).

The species of 7d. Schoenoplectus sect. Supini produce two morphologically different types of achenes. They have solitary, pistillate (amphicarpic) flowers enclosed in basal leaf sheaths in addition to the terminal inflorescences on the culms. In amphicarpic flowers perianth bristles are usually absent, when present, 1–2, caducous, and sparsely spinulose; the styles are (2–)3-fid, greatly elongated, stigmas are exserted from sheath orifices; achenes are larger than those found in normal spikelets, and their shape and surface sculpturing are different (A. E. Schuyler 1969; J. Raynal 1976; J. Browning 1992).

Schoenoplectus includes some difficult species complexes, each with different ranges outside of North America, that are discussed under the first species in each complex. The four sections recognized here were delineated by S. G. Smith and E. Hayasaka (2001). About ten species from eastern Asia and Africa have not yet been assigned to a section.

Schoenoplectus californicus and members of the S. lacustris and S. pungens complexes are often ecologically dominant in wetlands, where they provide valuable food and habitat for waterfowl and other animals. In North America their culms are used, mostly historically, for making mats, baskets, chair seats, houses, boats, and other objects. Some species are cultivated as ornamentals. Indicator boxes for weediness are marked here on the basis of the status listed under Scripus.

Users of this treatment should note the following features: colors of unripe achenes, even when they appear to be mature, are usually much paler than ripe achenes; lengths of achenes include beak; lengths of scales include awn; spikelets usually elongate during flowering; and culm thicknesses refer to the middle third of culm.

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

Key
1. Spikelet scale apices clearly emarginate to 2-fid; culms (1–)2–15 mm diam.; plants perennial, with rhizomes long, tough, firm, not concealed among culm bases [7a. Schoenoplectus sect. Schoenoplectus].
→ 2
1. Spikelet scale apices entire (sometimes very obscurely emarginate); culms (0.5–)2(–3) mm diam.; plants perennial, with rhizomes long, weak, soft, or tufted annuals or perennials with rhizomes short, concealed among culm bases.
→ 1
2. Culms usually cylindric throughout, occasionally trigonous distally; inflorescences branched.
→ 3
2. Culms clearly trigonous throughout; inflorescences branched or not.
→ 6
3. Perianth members 2–4, straplike, fringed with soft, blunt hairs, dark red-brown; spikelet scales smooth or awn sparsely scabrous; leaf blades on distal sheaths absent or to 20 mm; culms clearly to obscurely bluntly trigonous near inflorescence.
S. californicus
3. Perianth members (4–)6(–8), bristlelike, spinulose, medium brown; spikelet scales densely scabrous to nearly smooth; leaf blades on distal sheaths present, 2–220 mm; culms cylindric throughout.
→ 4
4. Achenes clearly trigonous; perianth bristles 4(–5), usually 2 much shorter; styles 3-fid; spikelet scales scabrous only on awn and distal part of midrib; spikelets all solitary or some in pairs.
S. heterochaetus
4. Achenes usually plano- or biconvex, rarely clearly trigonous; perianth bristles (4–)6(–8), usually nearly equal; styles 2-fid or 2–3-fid, rarely all 3-fid; spikelet scales scabrous on awn, midrib, and often flanks, especially in proximal parts of spikelets; spikelets all clustered to all solitary.
→ 5
5. Spikelet scale awns straight to bent, 0.2–0.8 mm; scales (except often midribs) uniformly orangish, or sometimes straw-colored and prominently spotted at 10X, flanks smooth or very sparsely (rarely densely) scabrous; spikelets often all solitary; widest air spaces in upper 1/4 of culm 1–2.5 mm wide.
S. tabernaemontani
5. Spikelet scale awns (sometimes broken off) mostly strongly contorted, rarely all straight, 0.5–2 mm; scales wholly or partly pale and prominently spotted at 10X, flanks sparsely to often densely scabrous; some spikelets always clustered; widest air spaces in upper 1/4 of culm 0.5 (east)–1.5(–2.5) (west) mm wide.
S. acutus
6. Inflorescences branched, or rarely some capitate or of 1 spikelet.
→ 7
6. Inflorescence unbranched (capitate) [Schoenoplectus pungens complex].
→ 8
7. Inflorescences to 2 times branched, of 1–35 spikelets; culms 2–4 mm diam. in middle; perianth members bristlelike, medium brown, spinulose.
S. triqueter
7. Inflorescences 3 or more times branched, of 25–150+ spikelets; culms 4–10 mm diam. in middle; perianth members straplike, dark reddish brown, with soft, blunt hairs.
S. californicus
8. Spikelet scale apex notch 0.1–0.4 mm deep, awns 0.2–0.6 mm; distal leaf blade much shorter than to nearly equaling, rarely 1.5 times longer than sheath; proximal inflorescence bract 1–6 cm, other bracts without blades; sides of mid culm deeply concave, rarely nearly flat.
S. americanus
8. Spikelet scale apex notch (0.3–)0.5–1 mm deep, awns 0.5–1.5(–2.5) mm; distal leaf blade much longer than to rarely equaling sheath; proximal inflorescence bract (1–)3–20 cm, other bracts with narrow blades often exceeding spikelets; sides of mid culm shallowly concave to nearly flat.
→ 9
9. Spikelets 1–5(–10); perianth bristles very stout to slender, unequal or equal, equaling achene to rudimentary; distal leaf blade several times longer than to rarely equaling sheath; achenes (2–)2.5–3.5 mm, plano- to unequally biconvex or obtusely trigonous; styles 2–3-fid.
S. pungens
9. Spikelets 3–35; perianth bristles very slender, some exceeding or equaling achene, some much shorter; distal leaf blade equaling to 1.5 times longer than sheath; achenes 1.9–2.6 mm, biconvex; styles 2-fid.
S. deltarum
10. Achenes smooth, 2.5–4.5 mm, trigonous; plants perennial with long rhizomes; leaf blades not erect, often flaccid [7b. Schoenoplectus sect. Malacogeton].
→ 11
10. Achenes rugulose or with sharp transverse ridges, 1–2.2 mm, plane or biconvex, sometimes trigonous; plants tufted annual (rarely perennial) with very short, inconspicuous rhizomes; leaf blades erect, not flaccid.
→ 13
11. Inflorescences branched; culms trigonous; leaf blades often flaccid and ribbonlike, 2–10 mm wide.
S. etuberculatus
11. Inflorescences unbranched, rarely 1-branched; culms trigonous or cylindric; leaf blades erect or flaccid and ribbonlike, 0.2–2 mm wide.
→ 12
12. Culms acutely trigonous throughout, 1.5–5 mm thick; leaf blades 1–2 mm wide, erect, emergent; spikelets 1–4.
S. torreyi
12. Culms cylindric or clearly trigonous distally, 0.5–1 mm thick; leaf blades 0.2– 1 mm wide, mostly flaccid, submerged; spikelets 1.
S. subterminalis
13. All leaves basal; spikelet scale midribs not keeled, flanks with 2–10 prominent ribs entirely or proximally; achenes rugulose, without prominent transverse, wavy ridges; amphicarpic flowers absent from leaf sheaths [7c. Schoenoplectus sect. Actaeogeton].
→ 14
13. One leaf (rarely 2) cauline distal to leaf sheaths; spikelet scale midribs prominently keeled distally, flanks without ribs; achenes with prominent transverse, wavy ridges; amphicarpic flowers often present in basal leaf sheaths [7d. Schoenoplectus sect. Supini].
→ 16
14. Culms acutely trigonous, 2–3 mm thick; leaf blades absent.
S. mucronatus
14. Culms cylindric, 0.5–2 mm thick; leaf blades present, at least on distal sheaths.
→ 15
15. Achenes mostly proximally rounded to stipelike constriction, base 0.3–0.4 mm wide; perianth bristles rarely absent, distinctly wider proximally; inflorescence bracts often divergent.
S. purshianus
15. Achenes mostly proximally evenly tapered, without stipelike constriction, base 0.2–0.3 mm wide; perianth bristles often absent, slender throughout; inflorescence bracts rarely divergent.
S. smithii
16. Achenes in spikelets nearly equilaterally sharply trigonous; styles all 3-fid.
S. saximontanus
16. Achenes in spikelets biconcave to plano-convex or obscurely compressed-trigonous; styles 2-fid or a few 3-fid.
→ 17
17. Achenes adaxially concave or sometimes nearly plane; spikelet scale flanks pale orange to nearly colorless.
S. hallii
17. Achenes adaxially longitudinally convex or horizontally slightly convex with convex center; spikelet scale flanks often distally orange- or red-brown.
S. erectus
Source FNA vol. 23, p. 47. FNA vol. 23, p. 44. Author: S. Galen Smith.
Parent taxa Cyperaceae > Schoenoplectus > sect. Schoenoplectus Cyperaceae
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
Subordinate 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. 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 subg. S.
Name authority (C. C. Gmelin) Palla: Verh. K. K. Zool.-Bot. Ges. Wien 38(Sitzungsber.): 49. (1888) (Reichenbach) Palla: Verh. K. K. Zool.-Bot. Ges. Wien 38(Sitzungsber.): 49. (1888)
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