Stipa nelsonii

HABIT Perennial; caespitose. Culms 60–100 cm long. Culm-internodes distally pubescent. Leaf-sheaths pubescent. Ligule an eciliate membrane. Leaf-blades flat, or involute; 10–20 cm long; 1–5 mm wide. Leaf-blade surface pubescent.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear; 10–20 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 7–15 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; unequally 2-toothed.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; membranous; without keels. Lower glume apex acuminate. Upper glume lanceolate; hyaline; without keels. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; subterete; 7 mm long; coriaceous; without keel; 5 -veined. Lemma surface pubescent; with conspicuous apical hairs. Lemma margins convolute; covering most of palea. Lemma apex awned; 1 -awned. Principal lemma awn bigeniculate; 30–50 mm long overall; with twisted column. Column of lemma awn pubescent. Palea 0.5 length of lemma; 2 -veined; without keels.

FLOWER Lodicules 3. Anther tip smooth.

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

NOTES Stipeae. Man. U.S. Gr. 2004.

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