Panicum virgatum florets.©2014 Katy Chayka.Minnesota Wild Flowers.minnesotawildflowers.info (Accessed 1/2017).

Panicum is a genus of perennial or annual, C3 or C4 grasses, with no overwintering rosette (see Dichanthelium genus). 

Leaves alternate; the junction of the stem with the base of the leaf blade (ligule) often hairy. 

Flowers (florets) dry, papery,  spikelets without awns, terminal flower with both stamens and ovary (perfect), other flowers below it may be empty or with stamens only; first bract of the whole spikelet (first glume) usually very short to tiny, second glume about the same length as the entire spikelet, green or colored usually with prominent veins; outer bract

Panicum capillare.ligule. Enrico Romani.luirig.altervista.org

(lemma) of the fertile floret hard, pale, inrolled over the innermost flower bract (palea); inflorescence branched (a panicle) or spike-like (a raceme, in which each spikelet has a short stem). Appearance of inflorescence is generally delicate with florets well defined. 

Panicum capillare.inflorescence.Andrea Moro.luirig.altervista.org (Accessed 3/2016).

Fruit dry, 1-seeded grain.

Notes: Susceptible to the rusts Puccinia dolosa, ‘Uromyces’ setariae-italicae, and Puccinia esclavensis (Watson and Dallwitz 1992 onwards).