Plants annual, 20–210 cm tall, sometimes branching from the lower nodes.
Culms with hairy internodes and shorthairy nodes.
Leaves sheaths not inflated or compressed, with spreading papillose-based hairs; blades 15–40 cm × 7–25 mm.
Inflorescences dense, usually nodding, 6–20 × 4–11 cm, included in or shortly exserted from the uppermost sheaths at maturity; branches appressed to spreading, spikelets confined to the distal portions; pedicels 1–9 mm.
Spikelets ovoid, 4–6 mm, usually glabrous.
Glumes lower glumes 2.8–3.6 mm, 50–75% as long as the spikelets, 5–7-veined; upper glumes 4–5.1 mm, slightly exceeding the upper florets, 11–13(15)-veined.
Lower lemmas 4–4.8 mm, 9–13-veined, similar to the upper glumes.
Lower paleas 50% or less the length of the upper florets.
Fertile upper lemmas 3–3.8 × 2–2.5 mm, leathery or hard, smooth or striate, more or less shiny.
Anthers 1–2 mm.
2 subspecies.
Panicum miliaceum has larger spikelets than Oregon’s other Panicum species. It has been cultivated as a grain crop for thousands of years. In North America, it is mainly grown for birdseed.