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 speciosa

HABIT Perennial; caespitose. Butt sheaths dark brown; pubescent. Culms erect; 25–90 cm long. Culm-nodes brown. Leaf-sheaths longer than adjacent culm internode. Leaf-sheath oral hairs lacking to pubescent. Ligule an eciliate membrane. Collar glabrous. Leaf-blades filiform; conduplicate; 5–42 cm long; 0.7–0.8 mm wide. Leaf-blade apex pungent.

INFLORESCENCE Inflorescence a panicle.

Panicle open; nodding; 7–14 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels ciliate; hairy all along but hairs longer above.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 25–40 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; curved; 3–3.5 mm long; pubescent; pungent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 1 length of upper glume; hyaline; without keels; 3–5 -veined. Lower glume surface asperulous. Lower glume apex acuminate. Upper glume lanceolate; 25–40 mm long; 2–2.5 length of adjacent fertile lemma; hyaline; without keels; 3–5 -veined. Upper glume surface asperulous. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; subterete; 11–14 mm long; coriaceous; without keel; 5 -veined. Lemma surface pubescent; hairy all along. Lemma margins convolute; covering most of palea. Lemma apex dentate; 2 -fid; with lobes 1–1.5 mm long; pubescent; surmounted by a ring of hairs; with this appendage 0.5–1 mm long; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 40–85 mm long overall; with 20–70 mm long limb; with twisted column; deciduous; limb glabrous. Column of lemma awn 10–25 mm long; plumose; with 5–10 mm long hairs. Palea 4.5–5 mm long; 0.8 length of lemma; 2 -veined; without keels.

FLOWER Lodicules 3. Anthers 3; 4.5–5 mm long; anther tip smooth. Stigmas 2. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; fusiform; 8–12 mm long; light brown. Hilum linear; 1 length of caryopsis.

DISTRIBUTION North America: northwest USA, southwest USA, and Mexico. South America: western South America and southern South America.

NOTES Stipeae. Torres 1994.

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