Dichanthelium aciculare, commonly known as needleleaf witchgrass, is a perennial graminoid in the family Poaceae found throughout the Americas.
Dichanthelium aciculare is a perennial grass forming distinct basal rosettes, with occasional branching from nodes above the base. Both basal and stem (cauline) leaves are produced during spring and fall. Culms are 15âÂÂ60 cm tall, with bearded nodes and long-pilose internodes. Leaf blades reach up to 8 cm in length; lower blades are 1âÂÂ6 mm wide, while the uppermost are less than 2 mm wide, and may be glabrous or pilose on both surfaces, with glabrous margins and often long cilia at the base. Sheaths are pilose or puberulent; ligules are ciliate and 1âÂÂ3 mm long. In the fall, blades become narrow and involute (0.5âÂÂ2 mm wide), and may be glabrous to sparsely pilose. Panicles are exserted, 2âÂÂ7 cm long and 1âÂÂ5 cm wide, with a glabrous or puberulent rachis and spreading-ascending branches that are scaberulous and occasionally pilose at the base. Spikelets are obovoid, 1.5âÂÂ2 mm long, borne on scaberulous pedicels. The first glume is glabrous, scarious, acute, and 0.6âÂÂ0.8 mm long. The second glume and sterile lemma are pubescent or puberulent, obtuse, and 1.6âÂÂ2 mm long. The fertile lemma and palea are 1.5âÂÂ1.8 mm long, nerveless or faintly nerved, yellowish to brownish at maturity, lustrous, and acute or obtuse. Grains are broadly ellipsoid to subglobose, yellowish or purplish, and about 1 mm long.
In the United States, D. aciculare is found from New Jersey south to northern Florida, west to Texas, Oklahoma, and Mexico. It is also found in the West Indies and northern South America. It grows in sandy woods and fields.