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 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, 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 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 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 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 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. Fruiting summer. Non-calcareous or calcareous fresh or brackish shores, marshes, meadows, fens, disturbed places; 0-2300 m; Alta., B.C., Man., N.B., N.W.T., Ont., Que., Sask.; Alaska, Ariz., Ark., Colo., Conn., Del., Idaho, Ill., Ind., Iowa, Kans., Ky., Maine, Mass., Mich., Minn., Miss., Mo., Mont., Nebr., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo. 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.
Perennial herb with long slender rhizomes, mat-forming 8 cm - 0.8 m tall Leaves: reduced to bladeless sheaths, basal, two per culm, margins fused and enclosing culm, not splitting, reddish basally, green to straw-colored upwards with a reddish brown apex, inflated, papery to membranous, with a blunt to nearly pointed apex that sometimes bears a tiny tooth. Flowers: minute, spirally arranged on the axis of the spikelet, lacking sepals and petals, with zero or four bristles, subtended by a scale. Bristles (when present) straw-colored to pale brown, often unequal, equal to or slightly longer than achene, stout. Stamens three, exserted. Anthers straw-colored to yellow, to 1.8 mm long. Pistil one. Style two-cleft. Fruit: a one-seeded achene, straw-colored, yellow, or brown, about 1 - 1.5 mm long and 0.5 - 1 mm wide, reverse egg-shaped to reverse pear-shaped with a rounded apex, biconvex, smooth (at 30X) or finely wrinkled (at 10-30X). Tubercle brown to whitish, tiny, pyramidal. Seed with a thin, non-adherent wall. Culm: unbranched, 8 cm - 0.8 m long, to about 1.5 mm wide, circular in cross-section, often bluntly eight- to twelve-ridged (when dry), spongy inside, enclosed basally by two fused sheaths. Spikelets: solitary, 3 - 18 mm long, 2 - 3 mm wide, egg-shaped to nearly cylindrical with a pointed apex, with 15 to 50 floral scales. Scales spirally arranged and overlapping, brown with a straw-colored to green midrib, 2 - 3.5 mm long, about 1.5 mm wide, egg-shaped with a rounded apex (lower) to lance-shaped with a pointed apex (upper), keeled.
Similar species: No information at this time.
Flowering: mid-May to mid-June
Habitat and ecology: Common in moist calcareous habitats such as marshes, ditches, and around lakes.
Occurence in the Chicago region: native
Etymology: Eleocharis comes from the Greek words heleios, meaning "dwelling in a marsh," and charis, meaning grace. Erythropoda means "red stem."
Author: The Morton Arboretum
FNA 2002
Common Name: bald spikerush Duration: Perennial Nativity: Native Lifeform: Graminoid General: Perennial mat forming with long rhizomes, 0.5-1.5 mm thick, with a cortex that breaks loose, internodes 5-30 mm, ephemeral scales 4-8 mm, membranous, not fibrous; terete stems 8-80 cm long, 0.5-1.5 mm thick. Vegetative: Leaves with upper sheaths persistent, not splitting, red to stramineous below, green to stramineous above, usually inflated, membranous to papery, broadly obtuse, tooth sometimes present. Inflorescence: Ovoid to lanceoloid or cylindric spikelets 3-18 mm by 2-3 mm, acute apex, lower scale stem clasping, entire, floral scales often spreading in fruit, 15-50, with 4-5 per mm on rachilla, brown to reddish brown; in lower part of spikelet ovate, rounded apex, in upper lanceolate, entire apex, acute, 2-3.5 mm by 1.5-2 mm; flowers with perianth bristles 4, light brown to stramineous, stout, equaling achene to slightly exceeding tubercle; achene not persistent, dark yellow, stramineous to dark brown, obovoid to obpyriform. Ecology: Found on shores, along marshes and meadows and disturbed areas from sea level to 7,500 ft (2286 m); flowers in summer. Notes: This is a very variable species, so a collection seems inevitable to establish identity. Especially as you-ll need a scope to figure out the scales. This species is generally rare, not likely. Only found in Arivaca cienega in the vicinity of Sonoran Desert parks. Ethnobotany: Unknown Etymology: Eleocharis is from Greek heleos or helos, a marsh, low ground, meadow and charis, grace, beauty, hence marsh grace, while erythropoda comes from Greek erythros for reddish, and poda for foot, or red footed. Synonyms: Eleocharis calva, Scirpus glaucus, Trichophorum palustre Editor: SBuckley, 2010