Agrostis idahoensis

HABIT Perennial; caespitose. Culms 10–30 cm long. Lateral branches lacking. Leaves mostly basal. Ligule an eciliate membrane; 1–2 mm long; erose, or lacerate; obtuse, or acute. Leaf-blades flat, or conduplicate; 0.5–1.5 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 5–10 cm long. Primary panicle branches ascending. Panicle branches capillary; flexuous; scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets elliptic; laterally compressed; 1.6–2.4 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus glabrous.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; shiny. Lower glume lanceolate; 1.6–2.4 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 1.6–2.4 mm long; membranous; 1-keeled; 1 -veined. Upper glume primary vein scaberulous. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile lemma elliptic; 1.3 mm long; hyaline; without keel; 5 -veined. Lemma lateral veins extending close to apex. Lemma apex muticous. Palea present, or absent or minute; 0–0.2 mm long; 0.1–0.2 length of lemma; hyaline.

FLOWER Lodicules 2; 0.2–0.3 mm long; membranous. Anthers 3; 0.3 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

DISTRIBUTION North America: northwest USA, southwest USA, and south-central USA.

NOTES Aveneae. Fl Pac NW 1994.

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