Trisetum rosei

HABIT Perennial; caespitose; clumped densely. Culms geniculately ascending; 20–40 cm long. Culm-internodes distally pubescent. Leaf-sheaths longer than adjacent culm internode; puberulous. Ligule an eciliate membrane; 2 mm long; truncate. Leaf-blades flat, or involute; 5–12 cm long; 3–5 mm wide. Leaf-blade surface puberulous; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; 6–10 cm long; 1–1.5 cm wide. Primary panicle branches 1–3 cm long. Panicle branches pubescent.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 6 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma; shiny; gaping. Lower glume lanceolate; 4 mm long; 0.75 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume margins ciliolate (above). Lower glume apex acute. Upper glume lanceolate; 5 mm long; 1–1.1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume margins ciliate (above). Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 4.5–5 mm long; membranous; shiny; keeled; 5 -veined. Lemma surface pilose. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; curved; 4 mm long overall; limb ciliate. Palea gaping; 1 length of lemma; hyaline. Palea keels scaberulous. Palea surface pilose; hairy on margins.

FLOWER Anthers 3.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION North America: Mexico.

NOTES Aveneae. Scribner & Merr. 2005.

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