Flora of North America species comparison

30-60 cm, bases orange-brown;

nodes 3-6;

basal branching intravaginal.

15-200 cm, not branching at the upper nodes;

basal branching intravaginal or extravaginal;

prophylls not evident, shorter than the leaf sheaths.

mostly glabrous, throats densely ciliate, basal sheaths reddish brown, flat and ribbonlike with age;

ligules varying within a plant, lower ligules 0.3-1 mm, densely hairy and ciliate, hairs 0.2-1 mm, often longer than the basal membrane, upper ligules to 2.5 mm, hyaline to scarious, glabrous or hairy, usually less hairy than the lower ligules, sometimes ciliate;

blades 10-30 cm long, 0.5-2 mm wide when flat, usually rolled, to 1 mm in diameter, abaxial surfaces glabrous, smooth, adaxial surfaces pilose.

mostly basal, not overwintering;

sheaths open to the base;

cleistogenes not present;

collars with tufts of hair on either side;

auricles absent;

ligules membranous, truncate or shortest in the center and rounded, edges usually ciliate, hairs at the outer edges often longer than the central membranous portion, ligules of the lower leaves glabrous or hairy, sometimes densely hairy, those of the upper leaves glabrous or sparsely hairy;

blades usually convolute, apices narrowly pointed, flag leaves longer than 10 mm.

10-15 cm, dense, frequently partially included in the upper leaf sheaths at maturity;

branches ascending.

panicles, often partially included in the upper leaf sheath;

branches straight.

16-24 mm.

5.5-24 mm, with 1 floret;

rachillas not prolonged beyond the floret;

disarticulation above the glumes, beneath the floret.

linear-lanceolate, glabrous, tapering from below midlength to the narrowly acute apices;

lower glumes 16-24 mm, 1-veined;

upper glumes 13-19 mm, 3-5-veined;

florets (6)8-10 mm;

calluses 0.8-1.6(3) mm, sharp;

lemmas densely and evenly hairy, hairs about 0.5 mm, without a pappus;

awns 35-45(80) mm, once-geniculate, first segment pilose, hairs 3-8 mm, terminal segment glabrous, smooth;

paleas 3.2-5.1 mm, 2/5 – 2/3 (4/5) the length of the lemmas, usually hairy, hairs about 0.5 mm.

unequal, usually longer than the floret, sometimes shorter, hyaline, 0-5-veined;

florets narrowly lanceoloid, terete;

calluses 0.2-1.6(3) mm, acute, less than or equaling the floret diameter, antrorsely strigose distally, hairs white;

lemmas thickly membranous, basal 2/3 scabrous or shortly pubescent, distal 1/3 often bearing a pappus of ascending to strongly divergent 3-8 mm hairs, sometimes glabrous or with appressed hairs shorter than 1 mm, margins not or only slightly overlapping at maturity, apices not fused into a crown, lobes to 0.2 mm, with a single, terminal awn, awn-lemma junction conspicuous;

awns 9-45(80) mm, persistent or deciduous, scabrous, weakly once- or twice-geniculate, first segment scabrous or pilose, terminal segment glabrous or pilose, smooth or scabrous;

paleas 1/3 - 1/2 as long as the lemmas, flat between the veins, membranous to hyaline, glabrous or sparsely pubescent, 2-veined, veins poorly developed, apices rounded to irregular;

lodicules 2-3, the third, if present, reduced;

anthers 3.

fusiform, not ribbed;

hila linear, x = unknown.

= 66, 68, about 74.