Eleocharis ovata (Roth) Roem. & Schult.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Tufted and apparently annual, but sometimes with slender, short, inconspicuous rhizomes within the tuft; stems 0.5–5 dm, several- to many-ribbed, 0.5–2 mm thick; spikelet 5–13 mm, ovoid, with many (seldom less than 40) fls; scales 1.7–2.5 mm, purplish or brownish, with greenish midstrip and paler, hyaline margins, the lowest one empty or floriferous; bristles mostly 6 or 7, brownish, retrorsely barbellate, equaling or surpassing the achene, or reduced or wanting; anthers 0.3–0.8 mm; style bifid or sometimes trifid; achene lenticular (even when the style is trifid), 1–1.5 mm, stramineous to olive or dark brown, smooth and shining; tubercle short, flattened, broad-based, appressed to the broad top of the achene; 2n=10. Marshes and other wet places, sometimes intertidal, widespread in the N. Hemisphere, and found throughout our range. (E. diandra, an intertidal ecotype; E. engelmannii; E. obtusa)