Biology:Agave attenuata

Short description: Species of flowering plant

Agave attenuata
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Monocots
Order:	Asparagales
Family:	Asparagaceae
Subfamily:	Agavoideae
Genus:	Agave
Species:	A. attenuata
Binomial name
Agave attenuata Salm-Dyck 1834
Synonyms
Agave attenuata var. compacta Jacobi Agave attenuata var. latifolia Salm-Dyck ex A.Terracc Agave attenuata var. paucibracteata Trel. Agave attenuata var. subdentata Cels ex Carrière Agave attenuata var. subundulata Jacobi Agave cernua A. Berger Agave debaryana Jacobi Agave glaucescens Hook. Agave kellocki Jacobi Agave pruinosa Lem. ex Jacobi Ghiesbreghtia mollis Roezl. (invalid)

Agave attenuata is a species of flowering plant in the family Asparagaceae, commonly known as the foxtail or lion's tail. The name swan's neck agave refers to its development of a curved inflorescence, unusual among agaves. Native to the plateaux of central west Mexico, as one of the unarmed agaves, it is popular as an ornamental plant in gardens in many other places with subtropical and warm climates.

Description

Although the plant can appear acaulescent, stems often reach 50 to 150 cm (20–60 in) in length, and old leaves fall off, leaving the stems visible. The leaves are ovate-acuminate, 50–70 cm (20–28 in) long and 12–16 cm (5–6 in) wide, pale in color, ranging from a light gray to a light yellowish green. There are neither teeth, nor terminal spines, although the leaves taper to soft points that fray with age. The numerous, broad, succulent, tapering leaves are slightly less rigid than the leaves of most Agave species; they are a bright glaucous gray to light yellowish-green and stingless.

The inflorescence is a dense raceme 2.5 to 3 meters (8 to 10 ft) high (usually curved), with greenish-yellow flowers, growing after many years. As with other Agave species, the plant dies following seed development, but numerous suckers consequently sprout, both from the base of the plant and from the flower raceme.

It has two subspecies:

• A. attenuata subsp. attenuata: Native to Central and Southwest Mexico and naturalized in Madeira and Libya.
• A. attenuata subsp. dentata (J.Verschaff.) B.Ullrich: Native to Northwest and Southwest Mexico.

Etymology

The Latin specific epithet attenuata means "with a narrow point".

Range

Specimens were sent to Kew Gardens by the explorer Galeotti in 1834, from an unspecified location in central Mexico. A more recent study has reported it from Jalisco, east to Mexico State, in small colonies at elevations of 1,900 to 2,500 meters (6,200 to 8,200 ft), but there have been few sightings, suggesting this agave is rare in the wild. IUCN reports the species from the states of Colima, Durango, Guerrero, Jalisco, Michoacán, Nayarit and Mexico State, at altitudes between 400 and 2,500 meters (1,300 and 8,200 ft) on volcanic rock cliffs within pine forests and transitional zones of tropical dry and temperate forests types in mountains. It is reportedly naturalized in Libya and Madeira and is widely spread through the Mediterranean and the rest of Macaronesia.

Cultivation

Dry seed capsules and seeds - MHNT

In cultivation, Agave attenuata is said to prefer relatively moist loamy soil, although it can cope with poor soil and dry conditions. It should be protected from direct sunlight in summer and from long periods of frost. It is hardy down to USDA Zone 9b.

Gallery

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  A specimen leaning as the floral stem grows

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  Flower raceme

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  Flowers close-up

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  Fruits developing following bloom

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  A cluster of A. attenuata starting to form their flower spikes (overhead view)

References

Wikidata ☰ Q1254225 entry