Spidergrass
Aristida ternipes
Family: Poaceae
Coarse, tufted, perennial grass with very open seed heads growing to about 4’ tall. Distinguished by being an erect, perennial three-awn bunchgrass with an open panicle, the branches possessing axillary pulvini (small appendages in the axils which force the branches open). This grass flowers in summer.
Recognized as two varieties in the region: var. gentilis has an 3 well developed awns with the two lateral ones shorter than the central. Var. ternipes has one well-developed awn and the other two highly reduced to absent.
Full to part sun, best on irrigation but may volunteer outside—less robust without extra irrigation. Reseeds readily. Great pioneer plant for restoring soils.
Fair to poor forage value. It greens up after the spring rains more rapidly than most grasses and is used most heavily at this time. It is grazed lightly after other, more palatable grasses begin to grow.
Aristida is from the Latin arista for awn, ternipes is from Latin terni, three and the suffix -pes referring to the stalk. This cosmopolitan genus comprises 306 species.
Found on rocky slopes and plateaus, as well as disturbed soils from 2,500-5,500 ft. from central to southern California, through Arizona, west to Texas; south through Mexico and Central America to South America.
Photo by Sue Carnahan, SEINET
Aristida schiedeana on iNaturalist
The flowers, photo by Patrick Alexander, SEINET
The can be purplish when freshly emerging, photo by Sue Carnahan, SEINET