GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Stipa hirticulmis

HABIT Perennial; caespitose. Butt sheaths not bulbous. Culms geniculately ascending; 30–60 cm long; wiry; 6–11 -noded. Culm-internodes distally hispid; with reflexed hairs. Culm-nodes glabrous. Leaf-sheaths glabrous on surface. Leaf-sheath oral hairs ciliate. Ligule an eciliate membrane; 0.5–1 mm long. Leaf-blades straight, or curved; 1.5–6 cm long; 1 mm wide. Leaf-blade surface pilose; hairy on both sides.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear; 8–16 cm long; 1–2 cm wide. Primary panicle branches ascending; 2–3 -nate; bearing 2–4 fertile spikelets on each lower branch. Panicle axis with lower internodes 1–4.2 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 2–13 mm long.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 7–10.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 0.7–1 mm long; pubescent; pungent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 6–8 mm long; 1.1–1.2 length of upper glume; chartaceous; much thinner on margins; without keels; 3 -veined. Lower glume apex acuminate. Upper glume lanceolate; 6–8 mm long; membranous; with hyaline margins; without keels; 3 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; subterete; 3.5–5 mm long; coriaceous; light brown; without keel; 5 -veined. Lemma surface villous. Lemma margins convolute; covering most of palea. Lemma apex surmounted by a ring of hairs; with this appendage 0.7–1 mm long; awned; 1 -awned. Principal lemma awn bigeniculate; 29–50 mm long overall; with 11–27 mm long limb; with twisted column. Middle segment of lemma awn 10–13 mm long. Column of lemma awn 8–10 mm long. Palea 3–4 mm long; 2 -veined; without keels. Palea surface pilose; hairy on back.

FLOWER Lodicules 2; 1–1.2 mm long; veinless. Anthers 3; 2 mm long; brown. Stigmas 2.

FRUIT Caryopsis fusiform; 3–4 mm long; light brown. Embryo 0.25 length of caryopsis.

DISTRIBUTION North America: Mexico.

NOTES Stipeae. Hatch et al 2004.

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