Aristida spiciformis

HABIT Perennial; caespitose. Culms erect; 50–100 cm long. Leaf-sheath oral hairs lacking, or ciliate. Ligule a fringe of hairs. Leaf-blades erect; flat, or involute; 15–30 cm long; 1–3 mm wide. Leaf-blade surface scabrous; rough adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted, or spiciform; linear, or oblong; 10–15 cm long. Primary panicle branches appressed.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 8–10 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 2 mm long; pubescent; pungent.

GLUMES Glumes similar; exceeding apex of florets; thinner than fertile lemma. Lower glume linear; 4 mm long; 0.5 length of upper glume; membranous; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acuminate; awned; 1 -awned. Lower glume awn 10–12 mm long. Upper glume linear; 8–10 mm long; 1.6 length of adjacent fertile lemma; membranous; 1 -veined. Upper glume lateral veins absent. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn 10–12 mm long.

FLORETS Fertile lemma linear; subterete; 5–6 mm long; coriaceous; 3 -veined. Lemma margins convolute; covering most of palea. Lemma apex awned; 3 -awned. Principal lemma awn 3-branched; spreading; with 20–30 mm long limb; with twisted column. Column of lemma awn 10–30 mm long. Lateral lemma awns spreading as much as principal; 20–30 mm long; subequal to principal.

FLOWER Anthers 3.

DISTRIBUTION North America: southeast USA. South America: Caribbean.

NOTES Aristideae. N Amer Fl 1994.

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