Eleocharis bolanderi |
Eleocharis suksdorfiana |
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Bolander's spikerush |
Suksdorf spikerush, Suksdorf's spike-rush |
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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 0.5–1.5 mm thick, scales persistent, 5–10 mm, thinly membranous, not fibrous; resting buds absent (non-resting buds on rhizome apex ellipsoid, 10 × 2–5 mm); caudices present, hard, 2 mm thick. |
Culms | subterete, often with to 6 prominent ridges when dry, sulcate, 10–30 cm × 0.3–0.5 mm, firm to rigid, spongy. |
erect, not spirally twisted, not contracted near spikelet, when dry usually with several blunt to acute ridges and sulcate, subterete to slightly compressed, to 2 times as wide as thick, (5–)10–40 cm × 0.5–1.2 mm, firm to hard, finely many-ridged at 10–20X; culm tufts not proximally bulbous. |
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 stramineous to brown or reddish proximally, green to stramineous distally, subtruncate to obtuse, membranous to papery; apex brown to red. |
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. |
5–10 × 2–4 mm; proximal scale usually empty, 3–5 mm, usually 1/2 or more as long as spikelet; floral scales 8–12 per spikelet, lanceolate (to ovate), 3.5–5 × 2–2.5 mm. |
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, equal, the longest equaling achene to exceeding tubercle, very slender, spinules dense; anthers 1.6–3.5 mm. |
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. |
medium brown to gray or dark brown, equilaterally trigonous to compressed trigonous, rarely some biconvex, 2–2.7 × 0.7–1.3 mm, apex tapered to a distinct stramineous beak 0.2–0.9 × 0.3–0.6 mm. |
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. |
0.4–0.5 × 0.3–0.5 mm. |
Eleocharis bolanderi |
Eleocharis suksdorfiana |
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Phenology | Fruiting late spring–summer. | Fruiting late spring–summer. |
Habitat | Fresh, often summer-dry meadows, springs, seeps, stream margins | Bogs, fens, wet meadows, springs, wet gravel near ponds |
Elevation | 1000–3400 m (3300–11200 ft) | (0–)1100–3300 m ((0–)3600–10800 ft) |
Distribution |
CA; CO; ID; NV; OR; UT
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CA; CO; ID; MT; NV; OR; UT; WA; AB; BC |
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.) |
Although Eleocharis suksdorfiana is usually included in E. quinqueflora, it clearly differs qualitatively as given in the key. A collection from hot springs in Ruby Valley, Elko County, Nevada, has stout perianth bristles less than half of the achene length and may represent an undescribed taxon related to E. suksdorfiana. Eleocharis suksdorfiana closely resembles E. rostellata in its achenes, tubercles, culms, and caudices; it differs in the presence of long horizontal rhizomes and the absence of stoloniferous culms. The achenes of E. suksdorfiana are often finely longitudinally ridged, but in E. rostellata they are often rugulose. Specimens from Coconino and Santa Cruz counties, Arizona, are probably E. suksdorfiana but lack achenes so cannot be identified with certainty. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23. | FNA vol. 23, p. 115. |
Parent taxa | Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleocharis > ser. Eleocharis | Cyperaceae > Eleocharis > subg. Zinserlingia |
Sibling taxa | ||
Synonyms | E. montevidensis var. bolanderi | E. paucifora var. suksdorfiana, E. quinqueflora var. suksdorfiana |
Name authority | A. Gray: Proc. Amer. Acad. Arts 7: 392. (1868) | Beauverd: Bull. Soc. Bot. Genève 13: 267. (1922) |
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