Flora of North America species comparison

(10)25-150 cm, erect or decumbent, branching, sometimes rooting at the lower nodes;

nodes 3-6.

with erect portion 10-85 cm, long-decumbent, rooting and branching at the lower nodes.

keeled, basal sheaths usually with papillose-based hairs, rarely glabrous;

ligules 0.3-1.5 mm;

blades 2-18 cm long, 1-6 mm wide, flat or involute, glabrous, scabrous, or pilose.

with papillose-based hairs or the upper sheaths glabrous;

ligules 1-4 mm;

blades 3-14 cm long, 2-9 mm wide, mostly glabrous but the adaxial surfaces with papillose-based hairs basally.

with 2-7 spikelike primary branches, these digitate or the rachises to 1 cm;

longest primary branches 20-25 cm, axes triquetrous, not winged, with spikelets in unequally pedicellate groups of 3(-5) on the basal ½ (J.

with (2)3-6 spikelike primary branches, these digitate or a few solitary branches below;

lowest nodes glabrous or with hairs less than 0.4 mm;

primary branches 6.5-21 cm long, 0.6-1.3 mm wide, axes winged, wings at least 1/2 as wide as the midribs, lower and middle portions bearing spikelets in unequally pedicellate pairs, pedicels not adnate to the branches;

secondary branches absent;

shorter pedicels about 0.2 mm;

longer pedicels to 2 mm.

1.3-2.8 mm.

2.6-3.7 mm, spikelet pairs dimorphic in their pubescence and venation pattern of the lower lemmas.

absent or to 0.1 mm;

upper glumes 1-2 mm long, from 3/4 to almost as long as the spikelets, almost glabrous or sparsely to densely pubescent with clavate to capitate hairs (use 20x magnification), glume apices rounded;

lower lemmas equaling the spikelets, glabrous or glandular-pubescent, 5-7-veined, veins unequally spaced, outer 3 veins on each side closer to each other than the midvein is to the inner lateral veins;

upper lemmas 1.3-2 mm, apiculate, dark brown at maturity;

anthers 0.3-0.6 mm.

absent or to 0.9 mm, deltoid or bifid;

upper glumes 1.7-2.8 mm, 1/2 - 3/4 as long as the spikelets, 3-veined;

lower lemmas 7-veined, veins smooth;

lower lemmas of shortly pedicellate spikelets with 3 equally spaced, glabrous or shortly pubescent central veins, lemma margins and the region between the 2 lateral veins with appressed or spreading, 0.5-1 mm hairs;

lower lemmas of long-pedicellate spikelets with unequally spaced veins, midvein well-separated from the 3 lateral veins, lateral veins crowded together near the margins, lemma margins and the region between the 2 inner lateral veins hairy with appressed or strongly divergent, 1-2 mm hairs, sometimes also with longer, glassy yellow hairs;

upper lemmas of all spikelets usually yellow or gray, sometimes light brown, at maturity;

anthers 0.5-0.6 mm.

, pers.

.).

= 36, 54.

= 54, 72.