Aristida californica

Thurb.
Common names: Mojave threeawn
Treatment appears in FNA Volume 25. Treatment on page 319.

Plants perennial; sometimes flowering the first year. Culms 10-40 cm, highly branched above the base in age; internodes glabrous or pubescent, sometimes nearly lanose. Leaves cauline; sheaths shorter than the internodes, glabrous or puberulent; collars glabrous or pubescent at the sides; ligules 0.5-1 mm; blades usually less than 6 cm long, 0.5-1 mm wide, pale green, involute, glabrous or puberulent abaxially. Inflorescences paniculate or racemose, 5-10 cm long, 1-2 cm wide, with few spikelets; rachis nodes glabrous or with straight hairs; primary branches 1-2 cm, appressed, without axillary pulvini. Spikelets appressed. Glumes unequal, 1-2-veined; lower glumes 4-10 mm; upper glumes 7-15 mm; calluses about 1 mm; lemmas 5-7 mm, purple or mottled, junction of the lemma and awns evident; awns twisted together basally into a 4-26 mm column, free portions 12-50 mm, those of the central and lateral awns similar in length, curved to arcuate basally, straight and divergent distally, disarticulating at the base of the column at maturity; anthers 3, about 2 mm long. 2n = 22.

Discussion

The range of both varieties of Aristida californica extends from the southwestern United States into northwestern Mexico.

Selected References

None.

Key

1 Cauline internodes puberulent to nearly lanose Aristida californica var. californica
1 Cauline internodes glabrous Aristida californica var. glabrata