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1 Inflorescences an open panicle (as long as wide); spikelets solitary (or paired or in 3’s) on long or short pedicels; pedicels mostly > 2× as long as the spikelets, mostly spreading (sometimes distally appressed on branches); the entire panicle usually detaching at maturity
1 Inflorescences of digitate or sub-digitate primary branches, or primary branches alternately arranged along a central axis; with (1) 2-3 (or more) spikelets per node on primary branches, arranged in two rows along one side of the branch; spikelets appressed on branches; the entire inflorescence not detaching at maturity.
..2 Inflorescences of primary branches alternately arranged along a central axis; all the rachilla internodes more or less conspicuously elongated, hence upper florets stipitate; upper lemmas dark brown at maturity; spikelets 3.0-6.6 mm long, densely short to long pubescent, hairs generally exceeding the length of the spikelet and hairs spreading at maturity; hairs smooth-walled, with acute apices
..2 Inflorescences of digitate or sub-digitate primary branches, or primary branches alternately arranged along a central axis; no conspicuous elongated rachilla internodes, upper floret not stipitate; upper lemmas pale yellow, tan, gray, purple-tinged, purple, brown or dark brown; spikelets 1.3-4.1 mm long, glabrous to variously pubescent; hairs various, smooth or verrucose walled, with acute or dilated apices.
......4 Spikelets in 2s on the middle portions of the primary branches, the pedicels not adnate; upper lemmas gray, yellow, and/or purple-tinged when immature, purple at maturity
........5 Spikelets 1.7-2.2 mm long; plants 3-10 dm tall; racemes to 10 cm long; upper sheaths glabrous, lower sheaths glabrous to sparsely pilose
........5 Spikelets 2.0-2.8 mm long; plants 8-15 dm tall; racemes to 25 cm long; upper sheaths glabrous or pilose, lower sheaths densely pilose
............ 7 Hairs of the spikelet minutely capitate; second glume ca. 1× as long as the first glume; spikelets 1.7-2.3 mm long
............ 7 Hairs of the spikelet not minutely capitate; second glume ca. 0.75× as long as the first glume; spikelets 1.2-1.7 mm long
............ ..8 Spikelets 1.5-1.8 mm long, villous with crinkled hairs; pedicels glabrous, terete in cross-section
............ ....9 Spikelets (1.7-) 2.5-3.4 mm long, averaging 3.0 mm long or shorter; leaf blades pilose over the upper surface
............ ......10 Lower lemma of the sessile spikelet with 5 equidistant nerves; lowermost inflorescence node glabrous or pubescent with hairs < 0.4 mm long; apex of the first glume rounded to truncate
............ ......10 Lower lemma of sessile spikelet with the lateral nerves crowded to the margins; lowermost inflorescence node pubescent with hairs > 0.4 mm long; apex of the first glume acute