Aristida patula

Chapm. ex Nash
Common names: Tall threeawn
Treatment appears in FNA Volume 25. Treatment on page 321.

Plants perennial; loosely cespitose, bases knotty, sometimes shortly rhizomatous. Culms (60)70-100 cm, stiffly erect, unbranched. Leaves cauline; sheaths longer than the internodes, mostly glabrous, summit with hairs; collars hispid, hairs 0.2-0.8 mm; ligules less than 0.5 mm; blades 20-55 cm long, 2-4 mm wide, light bluish-green, flat to loosely folded, glabrous abaxially, scabridulous adaxially. Inflorescences paniculate, 30-50 cm long, 15-25 cm wide; rachis nodes glabrous or with straight hairs shorter than 0.5 mm; primary branches 8-22 cm, ascending to divaricate or drooping, with axillary pulvini, basal portion without spikelets. Spikelets appressed along the branches. Glumes brown to purplish, 1-veined, with a 1-2 mm awn; lower glumes 10-13 mm, slightly longer than the upper glumes; calluses 0.5-1 mm; lemmas 10-12(15) mm, glabrous, light gray to brownish, narrowing to a beak, beak less than 7 mm, not or only slightly twisted, junction with the awns not conspicuous; awns unequal, not disarticulating at maturity; central awns 20-25 mm, straight; lateral awns 3-10 mm, to 1/2 as long as and about 1/2 as thick as the central awns, usually divergent; anthers 3, about 3 mm, yellow-green. Caryopses about 8 mm. 2n = unknown.


Aristida patula grows in sandy fields, low pinelands, and roadsides. It is endemic to Florida.

Selected References


Lower Taxa