Eleocharis baldwinii |
Eleocharis erythropoda |
|
---|---|---|
Baldwin's spike-rush |
bald spike-rush, red-footed spikesedge, red-stem spikerush, redfoot spike-rush, spikesedge, éléocharide à tiges rouges |
|
Habit | Plants annual(?), often mat-forming, often stoloniferous, sometimes entirely vegetative; rhizomes absent. | Plants perennial, mat-forming; rhizomes evident, long, 0.5–1.5 mm thick, soft to firm, cortex often breaking loose, longer internodes 5–30 mm, scales often fugaceous, 4–8 mm, membranous, not fibrous. |
Culms | often arching, sometimes spotted or streaked red-brown, quadrangular or broadly elliptic, sulcate or not, 0.5–25(–30) cm × 0.1–0.4 mm, soft. |
terete, often with 8–12 blunt ridges when dry, 8–80 cm × 0.3–1.4 mm, firm to soft, internally spongy. |
Leaves | distal leaf sheaths persistent or disintegrating, stramineous, green, red-brown, or spotted or streaked red-brown, membranous, translucent, apex obtuse or acute. |
distal leaf sheaths persistent, not splitting, proximally red (to stramineous), distally green to stramineous, usually inflated, often callose, membranous to papery, apex often red-brown, broadly obtuse to subacute, tooth sometimes present, to 0.1 mm. |
Spikelets | basal spikelets usually present, pistillate; often proliferous, ovoid, ellipsoid, or linear, clearly laterally compressed, 2.3–6.9 × 0.5–2 mm, apex acute, proximal scale empty, amplexicaulous, similar to floral scales (midribs sometimes more prominent and sometimes slightly prolonged beyond lamina); subproximal scale with a flower; floral scales clearly distichous, 3–9, 3–4 per mm of rachilla, yellowish, pale brown, or red-brown, spotted, streaked, or mottled red-brown, narrowly ovate to oblong, (1.5–)2–5 × 0.4–0.6(–1.2) mm, membranous, apex rounded, obtuse or rarely acute, midribs keeled. |
ovoid to lanceoloid or nearly cylindric, 3–18 × 2–3(–4) mm, apex acute (to obtuse); proximal scale amplexicaulous, entire; subproximal scale with flower; floral scales often spreading in fruit, 15–50, 4–5 per mm of rachilla, medium brown to sometimes red-brown, midrib regions mostly stramineous to green, in proximal part of spikelet ovate, apex rounded, in distal part lanceolate, apex entire, acute, 2–3.5 × 1.5–1.7 mm, mostly carinate. |
Flowers | perianth bristles 3–7, incurved, colorless, white, or red-brown, shorter than or equaling achene; spinules sparse, retrorse, sharply acute; stamens 3; anthers 1.4–2.2 mm; styles 3-fid. |
perianth bristles 4 or absent, light brown to stramineous, stout, usually equal, equaling achene to slightly exceeding tubercle; stamens 3; anthers dark yellow to stramineous, 1–1.8 mm, apiculate; styles 2-fid. |
Achenes | whitish or greenish, spotted dark green, obovoid, trigonous, angles prominent, 0.6–0.9 × 0.4–0.6 mm, apex constricted proximal to tubercle, smooth to finely cancellate at 10–20X. |
not persistent, dark yellow, stramineous, or dark brown, obovoid to obpyriform, biconvex, angles obscure, 0.9–1.6 × 0.7–1.2 mm, apex rounded, neck absent to long, smooth at 30X, or sometimes finely rugulose at 10–30X with 20 or more horizontal ridges in a vertical series. |
Tubercles | pale to red-brown, pyramidal, trigonous, 0.2–0.3(–0.4) × 0.2–0.5 mm. |
brown to whitish, pyramidal, much higher than wide to, lower than wide, 0.35–0.65 × 0.2–0.6 mm. |
2n | = 16, 18, 19, 20. |
|
Eleocharis baldwinii |
Eleocharis erythropoda |
|
Phenology | Fruiting early spring–winter. | Fruiting summer. |
Habitat | Freshwater to moist terrestrial sites, pine savannas, cypress ponds, lakeshores | Non-calcareous or calcareous fresh or brackish shores, marshes, meadows, fens, disturbed places |
Elevation | 0–60 m (0–200 ft) | 0–2300 m (0–7500 ft) |
Distribution |
AL; AR; FL; GA; LA; MS; NC; SC; TX
|
AK; AR; AZ; CO; CT; DE; IA; ID; IL; IN; KS; KY; MA; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NY; OH; OK; OR; PA; RI; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NT; ON; QC; SK
|
Discussion | Coarse plants of Eleocharis baldwinii usually bear more achenes per spikelet, dark colored achenes, culms gray-green when dried, and yellowish sheaths. Finer plants often bear few achenes per spikelet, whitish achenes, culms that are mid green when dried, and reddish sheaths. Achene color may relate to maturity, with darker achenes being fully mature. Although these variants appear to intergrade, they may be recognizable taxonomically. The longer floral scales in the spikelet are usually 3.5– 5 mm. We have not seen vouchers to verify the report of Eleocharis baldwinii from Virginia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Eleocharis erythropoda is extremely variable. Intermediates with E. palustris variant b are common in the region of sympatry in the East, and with E. macrostachya variant b in the West, and E. erythropoda is sometimes difficult to distinguish from E. uniglumis. Eleocharis calva Torrey is an invalid name. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 98. | FNA vol. 23, p. 75. |
Parent taxa | Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleocharis > ser. Tenuissimae | Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleocharis > ser. Eleocharis |
Sibling taxa | ||
Synonyms | Chaetocyperus baldwinii | Scirpus glaucus |
Name authority | (Torrey) Chapman: Fl. South. U.S., 519. (1860) | Steudel: Syn. Pl. Glumac. 2: 76. (1855) |
Web links |
|