Calamagrostis valida

HABIT Perennial; caespitose. Rhizomes elongated. Culms 60–100 cm long. Ligule an eciliate membrane. Leaf-blades erect; involute; 10–30 cm long; 4–8 mm wide; stiff. Leaf-blade surface pilose; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong, or pyramidal; 10–20 cm long. Primary panicle branches 2–5 cm long. Panicle branches flexuous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 5.5–6 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus bearded. Floret callus hairs 1.5–3.5 mm long.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; gaping. Lower glume lanceolate; 5.5–6.5 mm long; 1 length of upper glume; membranous; much thinner above; much thinner on margins; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex attenuate. Upper glume lanceolate; 5.5–6.5 mm long; 1.3–1.5 length of adjacent fertile lemma; membranous; much thinner above; with hyaline margins; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex attenuate.

FLORETS Fertile lemma lanceolate; 3.5–5 mm long; membranous; without keel; 3 -veined. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; geniculate; 5–10 mm long overall; with twisted column. Rhachilla extension 1–2 mm long; pilose; with 1.5–3 mm long hairs.

FLOWER Lodicules 2. Anthers 3. Stigmas 2.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform. Disseminule comprising a floret.

DISTRIBUTION North America: Mexico.

NOTES Aveneae. Fl Nov Gal 1994.

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