dcsimg

Description

provided by Flora of Zimbabwe
Annuals or perennials. Spikelets 1-flowered, disarticulating above the glumes, in terminal, lax or contracted, panicles; glumes persistent, narrow, usually 1-nerved. Lemma narrow, with hard callus at base, with or without a beak or twisted column; articulation present or 0, usually visible as a transverse darker line on the body of the lemma, occurring at the apex of the lemma or at the apex of the column; awns 3 (1 central, 2 lateral) or rarely 1, glabrous.
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Mark Hyde, Bart Wursten and Petra Ballings
bibliographic citation
Hyde, M.A., Wursten, B.T. and Ballings, P. (2002-2014). Aristida Flora of Zimbabwe website. Accessed 28 August 2014 at http://www.zimbabweflora.co.zw/speciesdata/genus.php?genus_id=150
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Mark Hyde
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Bart Wursten
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Petra Ballings
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Flora of Zimbabwe

Aristida

provided by wikipedia EN

"
Pineland three-awn (A. stricta) flowers

Aristida is a very nearly cosmopolitan genus of plants in the grass family.[4][5] Aristida is distinguished by having three awns (bristles) on each lemma of each floret.[6] The genus includes about 300 species found worldwide, often in arid warm regions. This genus is among those colloquially called three-awns wiregrasses, speargrasses and needlegrasses.[7][8][9] The name Aristida is derived from the Latin "arista", meaning "awn".[10]

They are characteristic of semiarid grassland. The Wiregrass Region of North America is named for A. stricta. Other locales where this genus is an important component of the ecosystem include the Carolina Bays, the sandhills of the Carolinas, and elsewhere, Mulga scrub in Australia, and the xeric grasslands around Lake Turkana in Africa. Local increases in the abundance of wiregrasses is a good indicator of overgrazing, as livestock avoid them.

Description

Aristida stems are ascending to erect, with both basal and cauline leaves. The leaves may be flat or inrolled, and the basal leaves may be tufted. The inflorescences may be either panicle-like or raceme-like, with spiky branches. The glumes of a spikelet are narrow lanceolate, usually without any awns, while the lemmas are hard, three-veined, and have the three awns near the tip. The awns may be quite long; in A. purpurea var. longiseta they may be up to 10 cm.

Species

Selected species include:

See also

References

  1. ^ Lectotype designated by Henrard, Meded. Rijks.-Herb. 54: 9 (1926)
  2. ^ Tropicos, Aristida L.
  3. ^ Kew World Checklist of Selected Plant Families
  4. ^ Linnaeus, Carl von. 1753. Species Plantarum 1: 82 in Latin
  5. ^ Tropicos, Aristida L
  6. ^ Watson, L. and M. J. Dallwitz. (2008). "The grass genera of the world: descriptions, illustrations, identification, and information retrieval; including synonyms, morphology, anatomy, physiology, phytochemistry, cytology, classification, pathogens, world and local distribution, and references". The Grass Genera of the World. Retrieved 2009-08-19.
  7. ^ Flora of China Vol. 22 Page 453 三芒草属 san mang cao shu Aristida Linnaeus, Sp. Pl. 1: 82. 1753.
  8. ^ Altervista Flora Italiana, genere Aristida includes photos, drawings, and range maps for several species
  9. ^ Atlas of Living Australia, kerosene grasses, Aristida L.
  10. ^ Merrit Lyndon Fernald (1970). R. C. Rollins (ed.). Gray's Manual of Botany (Eighth (Centennial) - Illustrated ed.). D. Van Nostrand Company. p. 174. ISBN 0-442-22250-5.
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Aristida: Brief Summary

provided by wikipedia EN
" Pineland three-awn (A. stricta) flowers

Aristida is a very nearly cosmopolitan genus of plants in the grass family. Aristida is distinguished by having three awns (bristles) on each lemma of each floret. The genus includes about 300 species found worldwide, often in arid warm regions. This genus is among those colloquially called three-awns wiregrasses, speargrasses and needlegrasses. The name Aristida is derived from the Latin "arista", meaning "awn".

They are characteristic of semiarid grassland. The Wiregrass Region of North America is named for A. stricta. Other locales where this genus is an important component of the ecosystem include the Carolina Bays, the sandhills of the Carolinas, and elsewhere, Mulga scrub in Australia, and the xeric grasslands around Lake Turkana in Africa. Local increases in the abundance of wiregrasses is a good indicator of overgrazing, as livestock avoid them.

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cc-by-sa-3.0
copyright
Wikipedia authors and editors
original
visit source
partner site
wikipedia EN