Plants annual or perennial; cespitose, sometimes rhizomatous. Culms 10-180 cm, glabrous or hispidulous; nodes 2-5, glabrous. Sheaths open, smooth or scabrous; auricles absent; ligules hyaline, glabrous, obtuse to acute; blades flat, smooth or scabrous over the veins. Inflorescences open panicles; branches drooping to ascending, smooth or scabrous. Spikelets dorsally compressed, with 1 floret; rachillas not prolonged beyond the fertile floret; disarticulation above the glumes. Glumes equal, equaling or exceeding the lemmas, membranous, smooth or scabrous; calluses blunt, glabrous; lemmascoriaceous, glabrous, lustrous, margins involute, obscurely 5-veined; paleas similar to the lemmas and partly enfolded by them; lodicules 2, free, glabrous, toothed or not toothed; anthers 3. Caryopses glabrous; hila 1/5 to nearly 1/2 the length of the caryopses. x = 4, 5, 7, 9. Name from an old Latin word for millet, an appellation which is associated with species in several different genera.
Milium is a circumtemperate genus of four species. All the species grow in mesic to dry mixed woods and dry open habitats. Milium effusum is native to the Flora region; M. vernale has become established here.
SELECTED REFERENCESCallihan, R.H. and D.S. Pavek. 1988. Milium vernale survey in Idaho County, Idaho. Idaho Weed Control Rep. 1988:153; Fernald, M.L. 1950. The North American variety of Milium effusum. Rhodora 52:218-222.