Yucca

Yucca queretaroensis in Mexico.

The yucca or Yucca (Yucca ) are a genus of the family of asparagus plants ( Asparagaceae ). It is a purely Neotropical genus with distribution area in Central America. The name " Yucca " is derived from the distant palm-like hair and the lily -like flowers. The term " Yucca " is misleading because it is not Palm plants in yuccas; also is possible with Yuca linguistic confusion.

  • 6.1 Notes and references
  • 6.2 Literature

Description

Palm lilies are perennial woody plants; some species form a trunk. Some species branch out. In the rosettes are sessile, simple, parallel venation, tough, pointed, rigid leaves. The leaf margins are toothed or rarely smooth.

Depending on the type plants that are older than ten years can flourish. In paniculate inflorescences that look like a large lily of the valley, there are many flowers together. The hermaphrodite, radial symmetry, the threefold flowers are bell-shaped or spherical. The six, often whitish bloom are the same diverse and free or fused at their base. There are six stamens present with stamens which are about as wide as the dust bag. Three carpels are fused into a superior ovaries. The often thick, white to dark green pen usually ends in a 1-2 mm wide, usually three-lobed stigma, but sometimes it is capitate.

Are formed capsule fruits or berries. Each fruit contains a lot of black, sometimes gray seeds.

Some species are frost-hardy, so they survive in our climate.

Ecology

Yucca is similar to the genus Ficus is a typical example of coevolution between insects and plants. All members of this genus are dependent on pollination by the yucca moth females; Ficus are fig wasps ( Agaonidae ). By transformation of the lower jaw button pollen are transported to Yucca flowers and there deposited active on the scars. At the same time eggs are laid in the flowers, their larvae then feed on the seeds. However, consumption is low, so that there is enough to develop seeds.

Dissemination

Yucca species occur mainly in arid and semi -arid regions of Mexico and the western United States and southern Canada (Yucca glauca ssp. Albertana ) ago. A few are widely used in the more humid regions of Mexico coastal plain and the eastern United States, the Main deposit extends to the Mexican-American border region. Due to the huge distribution areas they are adapted to different environmental conditions. In mountain regions up to altitudes of 2700 meters (Yucca harrimaniae, Utah ) as well as in coastal regions (Yucca filamentosa, Virginia).

Their occurrence extends from the Sonoran Desert, Chihuahuan Desert, Sierra Madre Occidental ( Mexican plateau between the Sierra Madre Oriental and Sierra Madre Occidental), to Sierra Madre del Sul, near the peninsula of Yucatan to Baja California. Few species are endemic to subtropical and tropical zones. As the epiphytic or terrestrial Yucca lacondonica in Northe Sierra de Chiapas or Yucca elephantipes in southeastern Mexico and Yucca yucatana in Belize and Guatemala.

Fritz Hochstätter cultured in Mannheim since 1976 he founded for the purpose of ex- situ conservation protection collection hardy yuccas and other exotics with detailed information on the origin. Material was deposited in the herbarium of the Botanical Gardens Heidelberg ( HEID ), the Botanical Garden Hamburg ( HBG ) and in the Snake River Plains Herbarium at the Boise State University in Idaho ( SRP). The Botanical Garden is home to Darmstadt since 2009 also a protective and Sichtungssammlung hardy yuccas.

System

The following classification of the genus follows Fritz Hochstätter.

The genus Yucca comprises about 50 species and 24 subspecies in five sections. Distinctive feature of the sections is the way of the opening of the fruits: There are aufreißende not aufreißende and crumbling fruit.

Species with fruits aufreißenden

The plants are tree structure with untersetztem, recently to large, branched or unbranched stem. They grow solitary or form groups. The root system is fibrous, with short or widely spreading rhizomes, which spread in all directions from the main trunk. Sometimes at Yucca elata aboveground runners are observed. The leaves are arranged variable ( stiff, straight, flexible, linear, lanceolate, sword- shaped). The leaf margins of some representatives are toothed or serrated, sometimes fibrous.

The inflorescence is arranged upright or tilted to one side. The bell-shaped flowers are cream-colored to white. You have six perianth. The fruit is globose, ovoid to cylindrical. The woody, soft, fleshy capsules have three identical seed compartments. The seeds are black, smooth or rough surface, sometimes with wings. The seeds are ripe, depending on site conditions in six to ten weeks.

Species with non aufreißenden fruits

The plants are tree structure with untersetztem short to large branched or unbranched stem. They grow solitary or form groups. The root system is fibrous, with short to far out broad trends underground rhizomes. The smooth or roughened leaves are arranged as required. The leaf edges are serrated and sometimes form fibers.

The inflorescence is arranged upright, tilted to one side or upside down. The flowers are bell-shaped to round and smell (Yucca faxoniana ). The fruit is globose to cylindrical, fleshy or spongy (Yucca brevifolia ). The surface of the seed is textured or smooth.

Key to the sections

  • Section Yucca Engelm. Syn: Sarcocarpa Series Faxonianae Hochstätter: Yucca carnerosana ( Trel. ) McKelvey
  • Yucca faxoniana ( Trel. ) coffin.
  • Yucca arizonica McKelvey
  • Blue Yucca (Yucca baccata Torr. ) Yucca baccata subsp. baccata
  • Yucca baccata subsp. vespertina ( McKelvey ) Hochstätter
  • Yucca baccata subsp. thornberi ( McKelvey ) Hochstätter
  • Yucca capensis Lenz
  • Yucca declinata Laferr.
  • Yucca decipiens Trel.
  • Yucca filifera Chabaud
  • Yucca grandiflora Gentry
  • Yucca jaliscensis Trel.
  • Yucca mixtecana Garcia- Mend.
  • Yucca periculosa Baker
  • Yucca potosina Rzed.
  • Yucca schidigera Roezl ex Ortgies
  • Yucca schottii Engelm.
  • Torrey yucca (Yucca torreyi Shafer )
  • Bayonet Yucca (Yucca treculiana Carriere )
  • Datillo - yucca (Yucca valida Brandegee )
  • Grey Yucca (Yucca aloifolia L.)
  • Giant Yucca (Yucca elephantipes rule)
  • Yucca lacandonica Gomez Pompa & J.Valdes
  • Yucca linearifolia Clary
  • Yucca madrensis Gentry
  • Yucca yucatana Engelm.
  • Section Endlichiana Hochstätter Yucca endlichiana Trel.
  • Section Clistocarpa Engelm. Joshua Yucca (Yucca brevifolia Engelm. ): Yucca brevifolia subsp. brevifolia
  • Yucca brevifolia subsp. jaegeriana ( McKelvey ) Hochstätter
  • Yucca brevifolia subsp. herbertii ( Webber ) Hochstätter
  • Section Chaenocarpa Engelm. Series Filamentosae Hochstätter Filaments of yucca (Yucca filamentosa L.): Yucca filamentosa subsp. filamentosa
  • Yucca filamentosa subsp. smalliana ( Fernald ) Hochstätter
  • Yucca filamentosa subsp. concava ( Haw. ) Hochstätter
  • Yucca cernua E.L.Keith
  • Yucca pallida McKelvey
  • Yucca queretaroensis Lujan
  • Yucca reverchonii Trel.
  • Yucca rigida ( Engelm. ) Trel.
  • Yucca rostrata Engelm. ex Trel.
  • Yucca rupicola Scheele
  • Yucca thompsoniana Trel.
  • Yucca harrimaniae Trel. Yucca harrimaniae subsp. harrimaniae
  • Yucca harrimaniae subsp. neomexicana ( Wooton & Standlschmaus. ) Hochstätter
  • Yucca harrimaniae subsp. sterilis ( Neese & Welsh ) Hochstätter
  • Yucca harrimaniae subsp. gilbertiana ( Trel. ) Hochstätter
  • Yucca angustissima Engelm. ex Trel. : Yucca angustissima Engelm. ex Trel. subsp. angustissima
  • Yucca angustissima subsp. toftiae ( Welsh ) Hochstätter
  • Yucca angustissima subsp. kanabensis ( McKelvey ) Hochstätter
  • Yucca angustissima subsp. avia ( James Lauritz Reveal ) Hochstätter
  • Yucca arkansana subsp. arkansana
  • Yucca arkansana subsp. louisianensis ( Trel. ) Hochstätter
  • Yucca arkansana subsp. freemanii ( Shinners ) Hochstätter
  • Yucca baileyi subsp. baileyi
  • Yucca baileyi subsp. intermedia ( McKelvey ) Hochstätter
  • Yucca elata subsp. elata
  • Yucca elata subsp. utahensis ( McKelvey ) Hochstätter
  • Yucca elata subsp. verdiensis ( McKelvey ) Hochstätter
  • Yucca glauca subsp. glauca
  • Yucca glauca subsp. stricta ( Sims ) Hochstätter
  • Yucca glauca subsp. albertana Hochstätter
  • Section Hesperoyucca Engelm. : Yucca whipplei Torr.: Yucca whipplei subsp. whipplei
  • Yucca whipplei subsp. caespitosa ( M.E.Jones ) A.L.Haines
  • Yucca whipplei subsp. intermedia A.L.Haines
  • Yucca whipplei subsp. percursa A.L.Haines
  • Yucca whipplei subsp. newberryi ( McKelvey ) Hochstätter
  • Yucca whipplei subsp. eremica Epling & A.L.Haines

Paleobotany

In 1990, a relative of the yucca from the Miocene was first described as a proto Yucca shadishii of northwestern Nevada, the most closely resembles Yucca brevifolia.

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