Plants perennial; cespitose. Culms 30-120 cm, erect, unbranched. Leaves basal and cauline, pale green, sometimes glaucous; sheaths longer or shorter than the internodes, glabrous except at the summit; collars densely to sparsely pilose or glabrous; ligules less than 0.5 mm; blades 8-30 cm long, 1-2 mm wide, usually flat, often curled at maturity. Inflorescences paniculate, 10-30 cm long, (4)8-26 cm wide; rachis nodes with straight hairs, hairs to 0.8 mm; primary branches 6-16 cm, abruptly spreading to divaricate, stiff to lax, with axillary pulvini, usually not spikelet-bearing below midlength. Spikelets appressed, rarely spreading. Glumes 1(3)-veined, brown or purple at maturity, acuminate; lower glumes 6-13 mm; upper glumes equaling or to 4 mm shorter than the lower glumes; calluses 0.8-1.2 mm; lemmas 10-15(17) mm, terminating in a strongly twisted, 2-4 mm awnlike beak, junction with the awns not conspicuous; awns not disarticulating at maturity; central awns 5-12 mm, markedly bent near the base; lateral awns absent or to 1(3) mm, erect; anthers 1.2-2.2 mm, brownish. Caryopses 6-8 mm. 2n = 22, 44.

Aristida schiedeana grows on rocky slopes and plains, generally in pinyon-juniper, oak, or ponderosa pine communities. Plants from the southwestern United States and northern Mexico belong to Aristida scheideana var. orcuttiana (Vasey) Allred & Valdés-Reyna, in which the lower glumes are usually glabrous and longer than the upper glumes, and the collar and throat are usually glabrous. Aristida schiedeana Trin. & Rupr. var. schiedeana grows in Mexico, Guatemala, Nicaragua, and Honduras, and has puberulent, equal glumes and pilose collars and throats.

FNA 2003

Common Name: single threeawn Duration: Perennial Nativity: Native Lifeform: Graminoid General: Tufted perennial grass with erect stems 30-120 cm, unbranched, with sheaths longer or shorter than the internodes, glabrous except at summit, collars densely to sparsely pilose or glabrous. Vegetative: Sheaths longer or shorter than the internodes, glabrous except at summit; collars densely to sparsely pilose or glabrous; ligules less than 0.5 mm; blades 8-30 cm long, 1-2 mm wide, usually flat, often curled at maturity. Inflorescence: Panicle 10-30 cm long, 8-26 cm wide; rachis nodes with straight hairs to 1 mm; primary branches 6-16 cm, abruptly spreading to divaricate, stiff to lax, usually not spikelet-bearing below midlength; spikelets appressed, rarely spreading; glumes brown or purple at maturity, subequal, lower 6-13 mm, upper slightly shorter; lemmas 10-15 mm, terminating in a strongly twisted, 2-4 mm awnlike beak; junction with awns inconspicuous; awns not disarticulating at maturity; central awns 5-12 mm, markedly bent near the base; lateral awns absent or to 1 mm, erect. Ecology: Found on rocky slopes and flats, generally in pi-on-juniper, oak and pine woodlands from 3,500-7,000 ft (1067-2134 m); flowers July-October. Distribution: s CA, AZ, c and s NM, sw TX; south to c MEX. Notes: Distinguished by being a perennial three-awn bunchgrass with pedicels and spikelets appressed to the panicle branches. Especially useful are the two awns which are 1 mm to absent and the central awn which is 5-12 mm and markedly bent at the base making it stick out at an angle away from the spikelet. Ours are of the variety, var. orcuttiana. Considered one of the better forage species among the three awns, it greens up early in the spring. Ethnobotany: Unknown Etymology: Aristida is from the Latin arista for awn, while schiedeana is of uncertain origin. Synonyms: None Editor: SBuckley 2010, FSCoburn 2014, AHazelton 2015