Vegetative Morphology | |
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| Plants | annual or perennial; tufted or cespitose, not rhizomatous. |
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| Culms | 25-200 cm, herbaceous, not branching at the upper nodes. |
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| Basal branching | usually intravaginal. |
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| Prophylls | shorter than the sheaths. |
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| Leaves | mostly basal. |
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| Ceistogenes | usually not developed. |
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| Sheaths | open. |
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| Auricles | absent. |
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| Ligules | membranous, sometimes stiffly so, upper and lower ligules similar or upper ligules longer than those below. |
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| Blades | prominently ribbed, usually tightly convolute when dry. |
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Reproductive Morphology | |
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| Inflorescences | terminal panicles, usually contracted. |
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| Spikelets | 12-90 mm, with 1 floret. |
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| Rachillas | not prolonged beyond the base of the floret. |
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| Disarticulation | above the glumes, beneath the floret. |
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| Glumes | much longer than the floret, hyaline to membranous, usually acuminate, 1-3-veined. |
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| Florets | 3-25 mm, terete to slightly laterally compressed. |
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| Calluses | (1)1.5-6 mm, sharp or blunt, antrorsely hairy. |
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| Lemmas | coriaceous to indurate, tan to brown, smooth, glabrous or hairy, hairs sometimes uniformly distributed, sometimes in lines, margins flat, slightly overlapping at maturity, apices awned, lemma-awn junction evident. |
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| Awns | 50-500 mm, persistent, usually once- or twice-geniculate, sometimes plumose in whole or in part, basal segment often strongly twisted. |
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| Paleas | from shorter than to subequal to the lemmas, glabrous, 2-veined, not keeled, flat between the veins, apices sometimes scarious, sometimes similar in texture to the body. |
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| Lodicules | 3, glabrous or pilose. |
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| Anthers | 3. |
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| Styles | 2(3,4), free at the base, if 3 or 4, then 1 or 2 distinctly shorter. |
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| Caryopses | fusiform, not ribbed. |
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Species Distribution Maps
Chromosome Number(s)x = 11 Additional NotesName from the Latin stipa, 'oakum' (a loose bunch of fibers), alluding both to the feathery inflorescences and the use of Stipa tenacissima L. [? Macrochloa tenacissima] as a source of cordage. As treated here, Stipa is a genus of 150-200 species, all of which are native to Eurasia or northern Africa. Until recently, the genus was interpreted as including almost all species of Stipeae with cylindrical florets. In several parts of the world, this broader interpretation still prevails. Jacobs et al. (in press) found that even the European members of Stipa included in their study appeared to be polyphyletic. The most appropriate circumscription of the genus, and its size, is difficult to determine in the absence of a study that encompasses the Eurasian and North African members of the tribe. Two species of Stipa grow in the Flora region. Stipa pulcherrima is cultivated as an ornamental; Stipa capensis has been introduced, probably accidentally.
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Name/Synonymy Publication InfoStipa L., Sp. pl. 1:78 (1753). TYPE: Stipa pennata L.
Treatment fromM.E. Barkworth. Stipa in Flora of North America, volume 24. In prep. Oxford University Press.
Fact Sheet Developed ByPedro Oñativia Lake © 2006.
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