Aristida desmantha

HABIT Annual; caespitose. Culms erect; 45–100 cm long; wiry. Lateral branches ample. Leaf-sheaths without keel; glabrous on surface, or pubescent, or pilose, or woolly. Ligule a fringe of hairs; 0.2–0.3 mm long. Leaf-blades flat, or involute; 25–40 cm long; 2–4.5 mm wide. Leaf-blade surface scabrous; rough adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 8–20 cm long. Primary panicle branches ascending. Panicle branches stiff; scabrous.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 10–13 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 2 mm long; pubescent; pungent.

GLUMES Glumes similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 10–13 mm long; 1 length of upper glume; membranous; 1 -veined. Lower glume lateral veins absent. Lower glume surface glabrous, or hispid. Lower glume apex acute; awned; 1 -awned. Lower glume awn 2–4 mm long. Upper glume lanceolate; 10–13 mm long; 1.3–1.4 length of adjacent fertile lemma; membranous; 1 -veined. Upper glume lateral veins absent. Upper glume surface glabrous, or hispid. Upper glume apex acute; awned; 1 -awned. Upper glume awn 2–4 mm long.

FLORETS Fertile lemma linear; laterally compressed; 7–10 mm long; coriaceous; yellow and purple; mottled with last colour; without keel; 3 -veined. Lemma margins convolute; covering most of palea. Lemma apex awned; 3 -awned. Principal lemma awn 3-branched; recurved at base of limb; with 20–35 mm long limb; with a straight or slightly twisted column; deciduous; abscissing from top of lemma. Column of lemma awn 1–2 mm long. Lateral lemma awns gyrate; 20–35 mm long; subequal to principal.

FLOWER Anthers 3.

DISTRIBUTION North America: north-central USA and south-central USA.

NOTES Aristideae. Gr Tex 1993.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.