Aristida tuberculosa is an annual C4 grass (Cerros-Tlatilpa and Columbus 2009); 30-80 cm tall; stems branched from base and lower nodes, joints enlarged, lower sheaths hairy.
Leaves alternate, 0.1-0.3 cm wide.
Flower spikelets 1-flowered, glumes almost equal 2-2.8 cm with short awn, lemma densely hairy at base, 1.1-1.4 cm, 3-awned, awns equal, fused at base in a twisted column 0.7-1.3 cm, free parts 3-5 cm; inflorescence open, lax, 10-30 cm long; blooming and fruiting Aug.-Oct.
Wetland status: NL.
Frequency in NYC: Very infrequent.
Habitat: Dry, sterile, soil in open areas, sandy fill, dunes.
Notes: Seeds eaten by a few birds and small mammals; plants eaten by rabbits.