Rothrock's Grama
Bouteloua barbata var. rothrockii
Family: Poaceae
Short lived perennial grass growing to about 2’ tall. Flowers August through October. Reseeds readily. Several characteristics distinguish this variety from the regular species: in var. rothrockii the awns are longer, the stems are usually less branched and the glumes more noticeably scaberulous rather than glabrous and shiny. The roots of var. rothrockii are often more developed to be clearly perennial, although weakly so.
Photo by J. Richard Abbott, iNaturalist
Bouteloua barbata var. rothrockii on SEINET
Bouteloua barbata var. rothrockii resembles B. parryi var. parryi, but can be easily distinguished from that taxon by the lack of papillose-based hairs on the keels of its upper glumes.
Full to part sun, longer lived on irrigation. Great pioneer plant.
Bouteloua species like Rothrock’s provide seeds for many birds and small mammals, including kangaroo rats, pocket mice, prairie dogs and jackrabbits. An important range grass in southern Arizona, sometimes covering large areas.
The genus, Bouteloua, is named for brothers Claudio (1774-1842) and Esteban (1776-1813) Boutelou Agraz, Spanish botanists and horticulturalists; The species, barbata, is from Latin barba, beard. The variety, rothrockii, is named for Dr. Joseph Trimble Rothrock (1839-1922), surgeon on the Wheeler expedition of 1873-1875. There are 57 species of Bouteloua found only in the Americas, with most diversity centered in the southwestern United States. Some botanists consider this to be a distinct species, Bouteloua rothrockii.
Found on dry rocky hillsides and sandy mesas from 2,500-5,500 ft. in southern California, and southern Nevada, east to southern Utah, Colorado and south through Arizona, New Mexico and Texas, south to southern Mexico.
A single plant, photo by Jaxon Lane, iNaturalist
Floral detail photo by Jaxon Lane, iNaturalist
The regular species, Bouteloa barbata var. barbata is an annual plant, usually less bold, smaller awns. Photo by Cecelia Alexander, iNaturalist