Aristida adscensionis

Aristida adscensionis  L.
Triple-awned grass

Family:  Poaceae

Habit:  Annual 1 to 8 dm. branched at base, purplish tinge, erect or spreading.

Distribution:  Dry open rocky sites and in shrubland.  San Luis Obispo County to the deserts.  Also in Texas, Kansas and Argentina.

Seed unit: Spikelet with caryopsis.

Seed:  Lower glume 5 to 7 mm., upper 8 to 10 mm.; lemma 6 to 13 mm.; 3 awns, 7 to 23 mm., equal length.  Tip is often beaked.  

Embryo:  Basal-lateral embryo area of seed caryopsis.

Purity instructions:   Pure seed definition: 
AOSA: PSU #13 - Single floret spikelet or floret with or without awns, provided a caryopsis with some degree of endosperm development can be detected.  Caryopsis or piece of broken caryopsis larger than one-half of the original size.

Lab notes:  Seeds often look like sticks and are attached to stems.  Many florets are without substance.

Average pure seed units per gram:  1352 seeds per gram (based on AOSA pure seed units only from seven (7) samples received for testing from 1993 to 2003).

Range of percent pure seed:   10% to 53%

Range of percent inert: 44% to 88%

Description of inert:   Plant material, chaff, broken seed, dirt, sticks.

Planting instructions:  400 seeds, TB, 21 days at 15-25°C; for fresh and dormant seed, prechill and GA3 recommended.

References:  (link to main reference page)
Hickman, J.C., Ed.  1993.  p. 1234.
Munz, P.A. and D.D. Keck.  1968.  p. 1535.
Ransom Seed Laboratory