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 tortuosa

HABIT Perennial; caespitose. Butt sheaths woolly; persistent and investing base of culm; with fibrous dead sheaths. Culms erect; zigzag; 15–45 cm long; 6–8 -noded. Culm-nodes pubescent. Ligule an eciliate membrane; 1–2 mm long; lacerate; truncate. Leaf-blades convolute; 1–8 cm long; 0.5–1.5 mm wide. Leaf-blade surface ribbed; scaberulous; rough abaxially; pubescent; densely hairy; hairy adaxially.

INFLORESCENCE Inflorescence a panicle; embraced at base by subtending leaf.

Panicle open; linear; 10–30 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 5–50 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 10–12 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 1 mm long; pubescent; unequally 2-toothed.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 10–12 mm long; 1.3 length of upper glume; membranous; without keels; 3 -veined. Lower glume apex acuminate. Upper glume lanceolate; 8–9 mm long; membranous; without keels; 3 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; subterete; 7–8 mm long; membranous; without keel; 5 -veined. Lemma surface villous. Lemma margins flat; covering most of palea. Lemma hairs 2–4 mm long. Lemma apex awned; 1 -awned. Principal lemma awn geniculate, or bigeniculate; 20–25 mm long overall; with twisted column. Column of lemma awn puberulous. Palea 2–3 mm long; 0.5 length of lemma; 2 -veined; without keels.

FLOWER Lodicules 3; 1–1.5 mm long. Anthers 3; anther tip smooth. Stigmas 2. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; fusiform. Hilum linear.

DISTRIBUTION South America: southern South America.

NOTES Stipeae. Matthei 1995.

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