Annual herb 15 cm - 1.3 m tall Leaves: alternate, two-ranked. Sheaths rounded, with bumpy-based hairs. Ligules membranous, fringed with hairs (hairs 0.5 - 1.5 mm long). Blades spreading, 5 - 40 cm long, 3 - 18 mm wide, linear, parallel-veined. Inflorescence: a branched arrangement of spikelets (panicle), lax, diffuse, 13 cm - 0.5 m long, 7 - 24 cm wide, usually over half as long as the plant, breaking off at maturity and becoming a tumbleweed. Fruit: a caryopsis, indehiscent, enclosed within the persistent lemma and palea. Culm: upright to ascending, often branched basally, green or reddish purple, 15 cm - 1.3 m long, round in cross-section. Nodes sparsely to densely soft-hairy. Spikelets: often reddish purple, 2 - 4 mm long, lance-shaped to ellipsoid. Glumes: unequal, herbaceous. Lower glumes one-third to one-half as long as spikelets, one- to three-veined. Upper glumes 1.5 - 3 mm long, seven- to nine-veined, with minutely rough midveins. Lemmas:: Lower lemmas similar to upper glumes, stiff, straight, 2 - 3 mm long, prominently veined towards the apex. Upper lemmas shiny, with rolled-up margins on the upper surface. Paleas:: Lower paleas absent. Upper paleas longitudinally lined. Florets:: Lower florets sterile. Upper florets bisexual, straw-colored, sometimes blackish, about half as wide as long when mature, pointed at the apex. Anthers three. Stigmas red.
Similar species: No information at this time.
Flowering: July to October
Habitat and ecology: Waste ground.
Occurence in the Chicago region: native
Etymology: Panicum comes from the Latin word panis, meaning bread, or panus, meaning "ear of millet." Capillare means hair-like.