Crabgrass

An annual weed. The stalk is erect or the lower part is inclined, the knees are bent upward, 10-80 cm in height, 2-3 mm in diameter, glabrous or pubescent. The leaf sheath is shorter than the internodes, hairless or sparsely pubescent; the ligule is 1-3 mm long; the blade is linear-lanceolate, 5-15 cm long, 4-12 mm wide, with a rounded base and thick edges. , slightly rough, pubescent or hairless. Racemes are 5-18 cm long, with 4-12 fingers borne on a main axis 1-2 cm long; the cob is straight or spreading, with broad wings on both sides and rough edges; the spikelets are oval-lanceolate. , 3-3.5 mm long; the first glume is small, short triangular, and veinless; the second glume has 3 veins, is lanceolate, about 1/2 of the spikelet in length, and is mostly pilose between the veins and on the edges; The lemma is as long as the spikelet, has 7 veins, the midrib is smooth, the distance between the veins on both sides is wide, hairless, the side veins have small spiny roughness, the interveins and edges are pubescent; the second lemma is almost leathery , gray-green, apex acuminate, as long as the first lemma; anthers are about 1 mm long. The flowering and fruiting period is from June to September. [