Eleocharis bolanderi |
Eleocharis cellulosa |
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Bolander's spikerush |
Gulf Coast spikerush, Gulfcoast spikesedge |
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Habit | Plants perennial, densely tufted; rhizomes caudexlike, mostly hidden by culms and roots, short, 1.5–3 mm thick, hard, cortex persistent, internodes very short, scales not evident. | Plants perennial; rhizomes 1–4 mm thick, soft to hard, longer internodes 3–7.5 cm, scales 5 mm, tubers absent. |
Culms | subterete, often with to 6 prominent ridges when dry, sulcate, 10–30 cm × 0.3–0.5 mm, firm to rigid, spongy. |
terete or obtusely trigonous, 30–80 cm × 1–5 mm, soft to hard, not septate-nodulose, internally spongy, transverse septa incomplete; plants never forming filiform, flaccid culms. |
Leaves | distal leaf sheaths persistent, not splitting, proximally brown, red, or stramineous, distally stramineous, green or reddish, papery, apex sometimes reddish, obtuse, rarely callose, tooth absent. |
distal leaf sheaths persistent, membranous, apex acute to acuminate, often prolonged into a slender awn to 4 mm. |
Spikelets | ovoid, 3–8 × 2–3 mm, apex acute to obtuse; proximal scale amplexicaulous, entire; subproximal scale with flower; floral scales spreading in fruit, 8–30, 4–5 per mm of rachilla, dark brown to blackish, midrib regions often stramineous or greenish, ovate to lanceolate, 2–3 × 1.5 mm, apex entire, acute, often carinate in distal part of spikelet. |
not proliferous, 14–54 × 3–5.6 mm; rachilla joints without winglike remnants of floral scales; proximal scale empty, amplexicaulous, 2.5–4.9 mm; floral scales 40–180, 2–3 per mm of rachilla, stramineous to pale brown, flanks sometimes minutely dotted reddish, usually with pale to dark brown, reddish, or purplish submarginal band, obovate to suborbicular, widest in middle, 3.4–4.5(–6) × 3–4.8 mm, cartilaginous, membranous toward margins, margins broadly translucent, membranous, apex rounded. |
Flowers | perianth bristles 3–6, whitish to stramineous, stout to slender, often unequal, from rudimentary to 1/2 of achene length; stamens 3; anthers dark yellow to brown, 0.9–1.4 mm; styles 3-fid. |
perianth bristles 6–7, medium brown to pale brown or reddish, slender, proximally slightly flattened, subequal to unequal, mostly exceeding achene, 2–3.4 mm, smooth or sometimes finely retrorsely spinulose; anthers reddish brown, 1.7–2.5 mm; styles 3-fid. |
Achenes | falling with scales, stramineous, rarely dark brown, ovoid to obpyriform, slightly to greatly compressed-trigonous, rarely thickly lenticular, angles prominent or abaxial angle obscure, 0.9–1.2 × 0.65–0.8 mm, apex narrowly to broadly truncate, neck short, often compressed more than body, at 20–30X finely rugulose with more than 20 horizontal ridges in a vertical series or reticulate or cancellate. |
brown, biconvex, obpyriform, 2.2–2.8 × 1.3–1.9 mm, markedly sculptured at 10–15X, each face with (17–)20–24 rows of isodiametric to slightly transversely elongated cells, apex narrowed to a stout, often pale, spongy region 0.8–1.1 mm wide at base, 1/2–3/4 of achene width. |
Tubercles | whitish to brown, pyramidal, lower than wide, often 3-lobed as viewed from the top, 0.1–0.3 × 0.4–0.65 mm. |
dark brown, lamelliform to pyramidal, 0.1–0.5 × 0.2–0.5 mm. |
Eleocharis bolanderi |
Eleocharis cellulosa |
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Phenology | Fruiting late spring–summer. | Fruiting late spring–winter. |
Habitat | Fresh, often summer-dry meadows, springs, seeps, stream margins | Brackish to saline marshes, shores, ditches, mostly coastal, often abundant or dominant |
Elevation | 1000–3400 m (3300–11200 ft) | 0 (Florida)–600 (Arkansas, Texas) m (0 (Florida)–2000 (Arkansas, Texas) ft) |
Distribution |
CA; CO; ID; NV; OR; UT
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AL; AR; FL; GA; MS; NC; SC; TX; Mexico; West Indies; Central America (Nicaragua)
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Discussion | Eleocharis bolanderi is clearly distinct from E. montevidensis, from which it differs in its dense, tufted habit with short, caudexlike rhizomes, its leaf sheaths without a tooth, its achene and tubercle shapes, and its acute floral scales. Specimens of Eleocharis bolanderi without rhizomes or achenes are easily confused with E. decumbens, which often may be distinguished by culms 0.5–2 mm wide, and spikelets with scales sometimes more than 3 mm long. The tubercles of E. bolanderi are usually poorly developed and much lower than wide; in E. decumbens they are usually well developed and about as high as wide. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 23. | FNA vol. 23, p. 118. |
Parent taxa | Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleocharis > ser. Eleocharis | Cyperaceae > Eleocharis > subg. Limnochloa |
Sibling taxa | ||
Synonyms | E. montevidensis var. bolanderi | |
Name authority | A. Gray: Proc. Amer. Acad. Arts 7: 392. (1868) | Torrey: Ann. Lyceum Nat. Hist. New York 3: 298. (1836) |
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