Eragrostis lutescens
Plants annual; tufted, without innovations. Culms (2)6-25 cm, usually erect, sometimes decumbent, glabrous, with elliptical, yellowish, glandular pits below the nodes. Sheaths with elliptical glandular pits, sparsely hairy at the throat, hairs to 2 mm; ligules 0.2-0.5 mm, ciliate; blades 2-12 cm long, 1-3 mm wide, flat to involute, abaxial surfaces scabridulous, bases with glandular pits. Panicles terminal, 4-10(15) cm long, 0.5-2 cm wide, narrowly elliptic, contracted, dense; primary branches alternate, usually appressed, occasionally diverging to 30° from the rachises, rachises and branches with glandular pits; pulvini glabrous; pedicels 1.4-10 mm, appressed or divergent. Spikelets 3.6-7.5 mm long, 1.2-2 mm wide, narrowly ovate, light yellowish, occasionally mottled with red¬dish-purple, with 6-11(14) florets; disarticulation acropetal, paleas persistent. Glumes subequal, ovate to lanceolate, hyaline; lower glumes (0.7)0.9-1.4 mm; upper glumes 1.2-1.8 mm; lemmas 1.5-2.2 mm, ovate, subhyaline, stramineous, veins greenish and conspicu¬ous, apices acute; paleas 1.2-2 mm, hyaline, keels scabridulous, apices obtuse; anthers 3, 0.2-0.3 mm, purplish. Caryopses 0.5-0.8 mm, pyriform except slightly flattened adaxially, smooth, light brown. 2n = unknown.
Distribution
Colo., N.Mex., Wash., Calif., Oreg., Ariz., Idaho, Nev.
Discussion
Eragrostis lutescens grows on the sandy banks of streams and lakes and in moist alkaline flats of the western United States at 300-2000 m. It has not been reported from Mexico.
Selected References
None.