Dichanthelium laxiflorum, commonly known as open-flower witchgrass, is a perennial graminoid in the family Poaceae that is found throughout the Americas.
Dichanthelium laxiflorum is a tufted perennial grass with culms 15âÂÂ45 cm tall, featuring usually bearded nodes and glabrous to slightly roughened internodes. Leaves are primarily located on the lower stem, with blades up to 16 cm long and 4âÂÂ15 mm wide, generally glabrous or rough-textured, and sometimes bearing appressed to spreading soft hairs. Ligules are ciliate and measure 0.5âÂÂ1 mm long. The vernal panicle is 4âÂÂ9 cm long and 3âÂÂ6 cm wide, with smooth or nearly smooth pedicels ranging from 1âÂÂ10 mm in length. Spikelets are ellipsoid, 1.6âÂÂ2.3 mm long. The first glume is scarious, acute, nerveless or 1-nerved, and 1.6âÂÂ2.3 mm long. The sterile palea is also scarious and measures 1.2âÂÂ1.6 mm. Fertile lemmas and paleas are hardened, usually nerveless or faintly nerved, lustrous, yellowish to brownish, and 1.5âÂÂ2 mm long. Grains are broadly ellipsoid, 1âÂÂ1.5 mm long, and whitish to yellowish.
In the United States, D. laxiflorum is found from Maryland south to Florida west to Texas and north to Indiana. It is also found in Mexico, Central America, and the West Indies. It grows in open or shaded woodlands, often in moist soil.