Tufted annual, 2–10(–20) cm; lvs to 10 cm × 0.5 mm, resembling the stems; spikes mostly 1–3 per stem, ovoid, 2–6 mm; scales numerous, 1–2 mm, firm, obovate, mucronate or (especially the lower) with a short awn-tip; achene 0.5–0.7 mm. Moist sandy soil; trop. Amer., n. to Me., Minn., and Wash. Most of our plants (as well as the tropical ones) belong to the var. micrantha, with the inner scale ± strongly reduced (sometimes bifid) or obsolete. Var. aristulata Coville (H. drummondii), with a relatively well developed inner scale ± equaling the achene, occurs chiefly in w. U.S., extending e. sporadically to Ohio.
