Proximal scale 1.2-2 × 0.8-1 mm. Flowers: perianth bristles 6, colorless, white or rarely pale or red-brown, 0.6-1 mm, shorter than to equaling achene; spinules retrorse, minute, barely evident at 45X. Achenes 0.35-0.5 mm wide. Tubercles pyramidal or birettaform, 0.1-0.2 × 0.1-0.3 mm. 2n = 10.
Fruiting spring-fall. Fresh, wet places in clearings in pine woods, depressions in cypress-black gum forests, lakeshores; 0-600 m; Ala., Fla., Ga., Ind., La., Md., Mass., Mich., Miss., N.J., N.C., Pa., S.C., Tenn., Tex., Va.
Annual herb, tufted or sometimes mat-forming 2 - 40 cm tall (may be longer in water) Leaves: reduced to bladeless sheaths, basal, two per culm, margins fused and enclosing culm, mottled or streaked with purple or reddish brown, membranous, translucent, with a narrowly pointed apex. Flowers: minute, spirally arranged on the axis of the spikelet, lacking sepals and petals, with six bristles, subtended by a scale. Bristles colorless or white (rarely brown or reddish), to 1 mm long, shorter than to equal the achene. Stamens three, exserted. Pistil one. Style three-cleft. Fruit: a one-seeded achene, white to olive to light brown, sometimes spotted, to about 1 mm long and 0.5 mm wide, reverse egg-shaped, constricted near tubercle, usually three-angled. Tubercle tiny, three-angled, depressed pyramidal. Seed with a thin, non-adherent wall. Culm: often arching to ascending, unbranched, soft, 2 - 40 cm long, to almost 0.5 mm wide, four-angled or widely elliptic in cross-section, enclosed basally by two fused sheaths. Spikelets: solitary, 2 - 11 mm long, 1 - 2 mm wide, egg-shaped to lance-shaped or oblong with a pointed apex, circular in cross-section, with a basal scale that is unlike to the floral scales. Basal scale often longer than floral scales, egg-shaped to lance-shaped, with a broad, thickened midrib that often extends beyond the apex. Scales spirally arranged and overlapping, 0.8 - 1.5 mm long, 0.4 - 0.8 mm wide, egg-shaped to elliptical, membranous.
Similar species: No information at this time.
Flowering: late June to early September
Habitat and ecology: Has been found in sand pits, along muddy paths, and in other moist areas.
Occurence in the Chicago region: native
Etymology: Eleocharis comes from the Greek words heleios, meaning "dwelling in a marsh," and charis, meaning grace. Microcarpa means tiny-fruited.
Author: The Morton Arboretum
From Flora of Indiana (1940) by Charles C. Deam
Our only specimens were found in moist sand in the bottom of a roadside ditch about 2 miles southeast of Tefft in Jasper County.