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DescriptionThis adventive grass is a summer annual about ½2' tall that is tufted at the base; its culms branch occasionally. The lower culms are decumbent, while the upper culms are ascending to spreading. Each slender culm is terete, glabrous, and pale green to pale purple. The blades of the alternate leaves are up to 4" long and 1/3" across; they are light to medium green or blue-green, rather flat, and mostly hairless; sometimes there are scattered white hairs toward the base of the blades. The inflated sheaths of the leaves cover most of the culms; these sheaths are finely veined, hairless, and the same color as the blades. The upper culms terminate in digitate clusters of 2-6 racemes. These racemes are very narrow, spike-like, and up to 5" long. Each raceme has 2 rows of spikelets and a flattened central stalk (or rachis) about 1 mm. across. These spikelets occur in pairs or individually along the racemes on very short pedicels. Each spikelet is about 2 mm. long, dark green or purplish green, ellipsoid or ovoid in shape, and flattened; it consists of a pair of glumes, a pair of lemmas, and a single floret. The outer sides of the spikelet consist of the 2nd glume and the outer lemma; the 1st glume is small and insignificant, while the inner lemma is dark-colored and hidden from view. The blooming period occurs from mid-summer into the fall. Pollination is by wind. The small seeds are ellipsoid or ovoid and flattened. The root system is shallow and fibrous. This grass reproduces primarily by reseeding itself, although it can spread vegetatively by forming rootlets at the lower nodes of its culms.