Aristida purpurea var. robusta Merr.
Purple Threeawn

This variety differs from Aristida purpurea longiseta in being taller and more robust, 30-50 cm. tall,
the shoots fewer, the blades longer, not in conspicuous basal tufts, the panicles longer and stiffer,
the branches more stiffly ascending rather than curved and flexuous, and the variety is commoner in the North,
where it ranges from Minnesota to Washington; in Kansas this variety is found scattered in the west two thirds.

Habit: 		Densely tufted glabrous perennial, often in large bunches, resembling Aristida longiseta.
Culms: 		15-30 cm. tall, rather rigidly erect, densely tufted, simple, with numerous curly leaves at the base.
Blades: 	Involute, scabrous or nearly smooth beneath, curved or flexuous, the basal up to 10 cm. long, the culm
		blades less than 5 cm. long.
Sheaths: 	Smooth to scabrous, mostly confined to the base of the stem, a tuft of hairs on each side at the summit.
Ligule: 	Short, hairy.
Inflorescence: 	Panicle 2-6 cm. long, narrow, strict, nearly simple, the spikelets commonly solitary or the lower
		in pairs on short, appressed scabrous pedicels.
Spikelets: 	12-17 mm. long, 1-flowered, narrow.
Glumes: 	1-nerved, acute but not awned, first 7-(11) mm. long, often scabrous on the keel, second 12-17 mm. long.
Lemmas: 	9-12 mm. long, firm, narrow, rigid, gradually narrowed to the summit, glabrous, except minutely scabrous
		in lines in the upper half, the pubescent callus 1.5 mm. long, triple awned, awns about equal, 2-5 cm. long,
		or the lateral awns a little shorter, divergent.
Palea: 		Thin, included in the lemma.
Habitat: 	Dry soil, plains and hills.  June-September.
Kansas Range: 	Southwest fourth.
Remarks: 	The numerous short, curly blades at the base of the plant are quite characteristic.