Flora of North America species comparison

in tufts, slender, 30–90(–115) cm, glabrous or slightly scabrous.

in tufts, usually filiform, very slender, 35–80 cm, base 1–2 mm thick, glabrous or nearly so, somewhat scabrous toward apex.

sheaths purplish, wingless, weakly ribbed, finely pilose or nearly glabrous;

contra-ligules reddish, triangular, rigid, distinctly ciliate;

blades distinctly grayish green and revolute when dry, linear, attenuate, keeled, 1–3(–5) mm wide, shorter than culms.

sheaths purple tinged, scarcely winged, glabrous or minutely pilose;

contra-ligules ovate, quite short, rigid;

blades attenuate, keeled, shorter than culms, 1–2.5 mm wide, usually glabrous or nearly so.

axillary 1–3, terminal 1, quite lax; stalked spikes or panicles 2–4, terminal one 3–4.5(–8.5) cm with 2–7 open fascicles 2–6(–9) mm wide, of 1–4 spikelets;

bracts subtending and overtopping inflorescence leaflike, broadly attenuate, scabrous.

axillary and terminal, fasciculate;

fascicles (1–)2(–3), 10–18 × 4–8 mm, each with 1–5 spikelets, the lateral on long filiform peduncles;

bracts subtending inflorescence leaflike, lanceolate, 3–9 cm, long acuminate-attenuate, usually glabrous.

bisexual (an occasional terminal staminate spikelet), few flowered, 3–5 mm;

staminate scales lanceolate, pistillate scales ovate-acuminate, with prominent green keel.

bisexual and staminate, brown, 3–6 mm;

staminate scales lanceolate-acuminate, pistillate scales ovate, midrib excurrent, awnlike.

whitish or gray between angles, obscurely trigonous, ovoid or globose, 2–2.5(–3) mm, smooth, base broadly attenuate, somewhat depressed between angles, trigonous, not porose, apex umbonate;

hypogynium obsolete, reduced to distinct brown band at base of achene.

brownish gray or with dark longitudinal bands, ovoid, 1.5–2 mm, smooth, shining, apex distinctly umbonate;

hypogynium somewhat reduced, obscurely 3-angled, low, covered with whitish siliceous, papillose-spiculose crust.