Bouteloua eriopoda

Plants perennial; often shortly rhizomatous, stoloniferous, stolons long, densely woolly-pubescent. Culms 20-60(75) cm, wiry, decumbent, rooting at the lower nodes; lower internodes densely woolly-pubescent. Sheaths mostly glabrous or sparsely pilose, usually pilose near the ligules; ligules 0.1-0.4 mm, of hairs; blades 2.5-6 cm long, 0.5-2 mm wide, scabrous adaxially, margins with papillose-based hairs basally. Panicles (1)2-16 cm, with (1)2-8 branches; branches 14-50 mm, persistent, densely woolly-pubescent basally, with 8-18 spikelets, axes terminating in entire, sometimes scarious apices; disarticulation above the glumes. Spikelets pectinate, with 1 bisexual floret and 1 rudimentary floret. Glumes unequal, smooth or scabrous; lower glumes 2-4.5 mm; upper glumes 4.5-8(9) mm, glabrous, scabrous, or withhairs, hairs to 0.5 mm, not papillose-based; lower lemmas 4-7 mm, pubescent basally, glabrous or sparsely puberulent distally, acuminate, central awns 0.5-4 mm, lateral awns absent or shorter than 1 mm; lower paleas acuminate, unawned; anthers 1.5-3 mm, yellow to orange; rachilla segment to second florets about 2 mm, with a distal tuft of hairs; upper florets rudimentary, an awn column terminating in 3 awns of 4-9 mm. Caryopses 2.5-3 mm. 2n = 20, 21, 28.

Boutloua eriopoda grows on dry plains, foothills, and open forested slopes, often in shrubby habitats, and also in waste ground. It is usually found between 1000-1800 m, but extends to 2500 m. Once a dominant in much of its range, under heavy grazing B. eriopoda persists only where protected by shrubs or cacti because it is highly palatable. Its range extends from the southwestern United States to northern Mexico.

FNA 2003, Gould 1980

Common Name: black grama Duration: Perennial Nativity: Native Lifeform: Graminoid General: Perennial, often rhizomatous, grass with long densely woolly-pubesent stolons; stems 20-60 cm, wiry, decumbent and rooting at lower nodes; lower internodes densely woolly-pubescent. Vegetative: Sheaths glabrous to sparsely pilose, pilose near ligules; leaves inconspicuous with sheaths mostly shorter at internodes, blades 2 mm or less broad, 2-6 cm long, margins with papillose-based hairs; ligule < 0.5 mm, ciliate. Inflorescence: Panicles 2-16 cm, with 2-8 branches; branches 1-5 cm, densely woolly-pubescent basally, with 8-18 spikelets, branch axes terminating in entire, scarious apices; disarticulation above the glumes; spikelets moderately pectinate along branch, each with 1 bisexual floret and 1 rudimentary floret; glumes unequal, smooth or glabrous, 6-9 mm long; fertile lemma bearded at base, otherwise glabrous, tapering above to stout terminal awn mostly 1-3 mm long and much reduced lateral awns; rudimentary floret reduced to a lemma with 3 long awns, these 4-8 mm long. Ecology: Dry sandy plains, foothills, rocky slopes, forested slopes, often in shrubby habitats and in waste ground from 3500-8500 ft (1067-2591 m); flowers July to October. Distribution: se CA, s NV, s UT, AZ, NM, s CO and w TX; n MEX. Notes: Distinguished by its erect to laying-down (decumbent) growth form; spreading and wiry stems rhizomes, and often long stolons, which are woolly. A quite useful diagnostic character when the plant is matured and dry are the dark colored internodes covered by silvery-pubescence, alternating along the stem with the straw-colored, non-hairy leaf sheaths; when fresh, the internodes are green and covered with silvery pubescence, and the leaf sheaths are green and non-hairy. Also helpful are the 14-50 mm long inflorescence branches which have tufts of hair at the bases and are relatively slender when compared with other perennial Boutelouas. Each spikelet has 3 awns emerging from it, making them reminiscent of an Aristida. This highly-palatable grass often decreases with high grazing pressure and dense stands can be indicative of healthy rangelands. Ethnobotany: Unknown, but other species in the genus have many uses. Etymology: Bouteloua named for brothers Claudio (1774-1842) and Esteban (1776-1813) Boutelou Agraz, Spanish botanists and horticulturalists; eriopoda means woolly-footed. Synonyms: Chondrosum eriopodum Editor: SBuckley 2010, FSCoburn 2014, AHazelton 2015