Danthonia unispicata

HABIT Perennial; caespitose; clumped densely. Culms 15–25 cm long; disarticulating at the nodes. Leaf-sheaths pilose. Ligule a fringe of hairs. Leaf-blades flat, or involute; 4–15 cm long; 1–3 mm wide. Leaf-blade surface pilose.

INFLORESCENCE Inflorescence comprising only a few spikelets; comprising 1(–3) fertile spikelets.

Spikelets appressed, or ascending; solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–4 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 15–18 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; pubescent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 13–18 mm long; 1 length of upper glume; membranous; without keels; 3 -veined. Lower glume apex acuminate. Upper glume lanceolate; 13–18 mm long; 2 length of adjacent fertile lemma; membranous; without keels; 3 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma elliptic; 7–9 mm long; chartaceous; without keel; 7 -veined. Lemma margins eciliate, or ciliate; hairy below. Lemma apex lobed; 2 -fid; incised 0.25 of lemma length; awned; 3 -awned. Principal lemma awn from a sinus; geniculate; 8–9 mm long overall; with twisted column. Lateral lemma awns arising on apex of lobes; 1–2 mm long; shorter than principal. Palea 2 -veined. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; fleshy; glabrous. Anthers 3.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

CLEISTOGENES AND VIVIPARY Cleistogenes present; in lower sheaths.

DISTRIBUTION North America: western Canada, northwest USA, and southwest USA.

NOTES Arundineae. Man US Gr 1993.

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