Flora of North America species comparison

60-120 cm, stiffly erect, unbranched.

30-80(100) cm, erect, unbranched.

basal or nearly basal;

sheaths shorter than the internodes, smooth and mostly glabrous abaxially, sometimes with a line of widely spaced, 0.5-1 mm hairs over the midvein, not disintegrating into threadlike fibers at maturity;

collars glabrous, sometimes with a few conspicuous hairs at the sides;

ligules 0.1-0.3 mm;

blades 15-50 cm long, 0.3-1 mm wide, tightly involute, stiff, yellow-green, abaxial surfaces villous on both sides of the midvein, at least on the basal portion, hairs 0.6-1.5 mm, adaxial surfaces densely scabrous or densely short pubescent.

mostly basal;

sheaths usually longer than the internodes, mostly glabrous, throat sometimes with hairs, not disintegrating into threadlike fibers;

collars glabrous or with hairs at the sides;

ligules 0.2-0.4 mm;

blades 10-25(30) cm long, 1-3 mm wide, usually flat, often curling like wood shavings when mature, glabrous.

paniculate, 20-35 cm, 5-8 mm wide;

nodes glabrous;

primary branches 2-5 cm, appressed, without axillary pulvini, with 4-12 spikelets, spikelet-bearing to the base.

spikelike panicles, 10-25 cm long, 1-3 cm wide;

nodes glabrous or with straight, about 0.5 mm hairs;

primary branches 2-6 cm, appressed, without axillary pulvini, with 2-8 spikelets.

appressed.

subequal, glabrous, light brown or tan, usually 1(2)-veined, bifid and awned, awns 1.5-2.5 mm;

lower glumes 7-10 mm;

upper glumes 6-9 mm;

calluses 0.4-0.6 mm;

lemmas 6-9 mm, glabrous, light-colored when young, reddish when mature, column 1-2 mm, not twisted, junction with the awns inconspicuous;

awns (7)10-15(22) mm, subequal, usually horizontally spreading or curving downward, not disarticulating at maturity;

anthers 3, about 3 mm, reddish-brown.

10-15(18) mm, brownish, acuminate to awned, awns to 3 mm;

lower glumes slightly shorter than to equaling the upper glumes, 1-2-veined;

calluses 1-1.8 mm;

lemmas 12-18 mm, glabrous, rarely sparsely pilose, terminating in a 3-6 mm twisted column, junction with the awns not conspicuous;

awns 20-35 mm, straight to curved basally, ascending distally, not disarticulating at maturity;

central awns 20-35 mm;

lateral awns slightly shorter than the central awns;

anthers 3, 1.3-1.9 mm.

4-5 mm, chestnut brown.

= unknown.

= 22.