Eragrostis silveana

HABIT Perennial; caespitose. Rhizomes short; knotty. Glands elongated. Culms erect, or geniculately ascending; 45–60 cm long. Culm-internodes glandular. Leaf-sheaths viscid; outer margin hairy. Ligule a fringe of hairs. Leaf-blades flat, or involute; 8–25 cm long; 2–4 mm wide; without exudate, or viscid. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 20–30 cm long; 10–15 cm wide. Primary panicle branches ascending, or spreading; 6–12 cm long. Panicle branches capillary; viscid; scabrous; bearded in axils.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 4–9 fertile florets; with diminished florets at the apex. Spikelets linear, or oblong; laterally compressed; 3.5–5 mm long; 1 mm wide; breaking up at maturity; rhachilla deciduous; disarticulating below each fertile floret.

GLUMES Glumes deciduous; similar; shorter than spikelet. Lower glume ovate; 1 mm long; 1 length of upper glume; chartaceous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 1–1.2 mm long; 0.7–0.8 length of adjacent fertile lemma; chartaceous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile lemma ovate; 1.4 mm long; 1 mm wide; chartaceous; purple; keeled; 3 -veined. Lemma lateral veins prominent. Lemma apex acute. Palea keels ciliate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; fleshy.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 0.6 mm long.

DISTRIBUTION North America: south-central USA and Mexico.

NOTES Eragrostideae. Gr Texas 1994.

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