Nassella

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Nassella
Nassella tenuissima.jpg
Nassella tenuissima
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
(unranked): Commelinids
Order: Poales
Family: Poaceae
Tribe: Stipeae
Genus: Nassella
E. Desv.
Species

many, see text

Nassella (needlegrass) is a New World genus of over 100 perennial bunchgrasses found from North America through South America. The Latin word nassa refers to "a basket with a narrow neck".[1] It is usually considered segregate from the genus Stipa and includes many New World species formerly classified in that genus.[2] As of 2011, The Jepson Manual includes Nassella within Stipa.[3]

Nasella is characterized by strongly overlapping lemma margins and reduced, veinless paleas. The lemma tips are fused into the "crown," a short membrane that surrounds the base of the lemma. The rim of the crown usually has hairs.

Many species form both cross-pollinating and self-pollinating florets in the terminal panicle. The self-pollinating florets have 1 – 3 small anthers; the cross-pollinating florest have 3 longer anthers. Some species have self-pollinating inflorescences hidden in their basal leaf sheaths. These hidden inflorescences lack glumes and usually lack awns.

Diversity[edit]

As of 2001, there were about 116 species in this genus.[4]

California species[edit]

Horticultural species[edit]

  • Nassella gigantea - giant feathergrass
  • Nassella tenuissima - Mexican feathergrass is an attractive, drought-tolerant bunchgrass with fine leaves and a narrow inflorescence that sways gracefully in the wind. However, it readily escapes from cultivation and takes hold in disturbed areas, such as sidewalk cracks, driveways, and tree wells. It is well established as a weed in the San Francisco Bay Area, California, and has been found as an escape in Oregon.

Other species[edit]

References[edit]

  1. ^ Nassella. The Jepson Manual.
  2. ^ Barkworth, M. E. Nassella E.Desv. Stipeae Pages. Intermountain Herbarium, Utah State University. June 13, 2003.
  3. ^ Stipa pulchra. The Jepson Manual.
  4. ^ Barkworth, M. E. and M. A. Torres. (2001). Distribution and diagnostic characters of Nassella (Poaceae: Stipeae). Taxon 50(2) Golden Jubilee Part 4, 439-68.
  5. ^ "History and Culture: State Insignia", California State Library, December 8, 2006.

External links[edit]