Aristida purpurascens

arrowfeather three-awn grass, arrowfeather threeawn
Family

Poaceae

Leaf Arrangement

alternate

Leaf Type

simple

Growth Form

graminoid

Flower Color

green

Flower Month

July - November

Height (meters)

0.4 - 1.0

Milky Sap

No

Armed/Unarmed

Unarmed

Origin

native

Lifespan

perennial

Growing Season

Warm season


Wetland Class

FACW

Prairie Coefficient of Conservatism

8

Field Characters

Aristida purpurascens can be distinguished from A. purpurea by its by glumes which are usually unequal, the first is 6-10 mm long and the second is 5-8 mm long. The lemma is 6-8 mm long. The awns are 1.5-2.5 cm long, all about equally divergent and the same thickness at their base. It can also be distinguished from A purpurea by its erect, unbranched inflorescence, and 1.5-2.5 cm long awns, while A. purpurea has a lax, arched, branched and leafy inflorescence and awns that are 2.4-5.6 cm long. Two annual species of Aristida, A. oligantha and A. longespica, occur in disturbed prairie. Aristida oligantha has lemma awns that are 4-7 cm long and nearly equal in length while A. longespica has lemma awns shorter than 3 cm and unequal in length.

Cultural Information

Seeds average approximately 789,000/lb.

Animal Use

The following information for the genus Aristida: Animals that eat its seeds: Pine-woods sparrows, white-footed mouse. Animals that eat the plant: Jack rabbit, white-footed mouse, white-tailed deer (Martin et al. 1951). It is an undesirable range plant and is considered an invader that will increase because of disturbance, given an opportunity. Poor forage.

Natural History

The specific name of this species, purpurascens, results from a purplish cast the plant has when mature. It grows best on sandy soils through the U.S. It is considered undesirable by rangeland managers and is an increaser under excessive grazing or mowin

Habitat

Sandy woods and openings.