GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Aristida rhizomophora

HABIT Perennial; caespitose. Rhizomes elongated; scaly. Culms erect; 65–80 cm long. Leaf-sheaths glabrous on surface. Ligule a fringe of hairs. Leaf-blades flexuous; flat, or conduplicate; 7–10 cm long; 1–2 mm wide. Leaf-blade surface glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear; 20–30 cm long. Primary panicle branches ascending; distant; bearing spikelets almost to the base.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 12–17 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 1 mm long; pubescent; acute.

GLUMES Glumes similar; exceeding apex of florets; thinner than fertile lemma. Lower glume linear; 8–14 mm long; 0.66–0.8 length of upper glume; membranous; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acuminate, or setaceously attenuate. Upper glume linear; 12–17 mm long; membranous; 1 -veined. Upper glume primary vein smooth. Upper glume lateral veins absent. Upper glume apex acuminate, or setaceously attenuate.

FLORETS Fertile lemma linear; subterete; 9–12 mm long; coriaceous; 3 -veined. Lemma margins convolute; covering most of palea. Lemma apex awned; 3 -awned. Principal lemma awn reflexed, or recurved at base of limb; with 18–24 mm long limb. Lateral lemma awns spreading as much as principal; 15–20 mm long; shorter than principal.

FLOWER Anthers 3.

DISTRIBUTION North America: southeast USA.

NOTES Aristideae. N Amer Fl 1994.

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