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DescriptionThis grass is usually an annual, although sometimes it is a biennial or short-lived perennial. It consists of a flowering culm with alternate leaves about 1-3' tall. The culm is pale green, terete, glabrous, and unbranched. The blades of the alternate leaves are up to 8" long and 1/3" (8 mm.) across; they are ascending to widely spreading, linear in shape, and rather floppy. The blades are medium green on both sides, shiny, and hairless; the base of each blade is wider than the sheath or the culm, around which there extends a pair of auricles. The leaf sheaths are pale green to pale reddish green, hairless, and longitudinally veined. At the apex of the culm, there develops a floral spike about 6-10" long, consisting of alternate spikelets along the rachis (flowering stalk). These spikelets are located edgewise along the rachis. The culm often undulates from one spikelet to the next. Each spikelet consists of a single outer glume and 8-20 lemmas with florets. In each spikelet, the ascending lemmas are arranged in 2 overlapping ranks. The glume (8-12 mm. in length) is longer than the lemmas, but shorter than length of the spikelet; it is linear-elliptic, convex along its outer surface, where there are 3-5 longitudinal veins. Each lemma is 6-8 mm. in length, linear-elliptic, and convex along its outer surface, where there are several longitudinal veins. The upper lemmas have awns (shorter than the length of the lemmas), while the lower lemmas frequently lack awns. Each lemma has a single floret with an ovary, 3 stamens, and a pair of feathery stigmata. The blooming period can occur from late spring to fall, but lasts only 2 weeks. The florets are wind-pollinated. Each fertile floret is replaced by an elongated grain. The root system is fibrous. This grass spreads by reseeding itself.