Английская Википедия:Allocasuarina verticillata

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Allocasuarina verticillata, commonly known as drooping sheoak, is a species of flowering plant in the family Casuarinaceae and is endemic to south-eastern Australia. It is a small dioecious tree that has drooping branchlets up to Шаблон:Cvt long, the leaves reduced to scales in whorls of nine to thirteen, the mature fruiting cones Шаблон:Cvt long containing winged seeds Шаблон:Cvt long.

Description

Allocasuarina verticillata is a small dioecious tree that typically grows to a height of Шаблон:Cvt and has fissured bark, the penultimate branchlets woody. The branchlets are up to Шаблон:Cvt long, the leaves reduced to spreading teeth Шаблон:Cvt long, usually arranged in whorls of nine to thirteen around the branchlets. The sections of branchlet between the leaf whorls are Шаблон:Cvt long, Шаблон:Cvt in diameter but broader at the end near the teeth. Male flowers are arranged in spikes Шаблон:Cvt long, with about 2.5 to 4 whorls per centimetre (per 0.39 in.), the anthers Шаблон:Cvt long. Female cones are sessile or on a peduncle up to Шаблон:Cvt long, the mature cones cylindrical to barrel-shaped, Шаблон:Cvt long and Шаблон:Cvt in diameter, containing dark brown, winged seeds Шаблон:Cvt long. Flowering occurs in all months.

Taxonomy and naming

Drooping sheoak was first formally described in 1788 by French naturalist Jean-Baptiste Lamarck who gave it the name Casuarina verticillata in Encyclopédie Méthodique, Botanique from a tree grown in the Jardin du Roi. In 1982, Lawrie Johnson transferred the species to Allocasuarina as A. verticillata in the Journal of the Adelaide Botanic Gardens. The specific epithet (verticillata) means "verticillate".

The 1889 book The Useful Native Plants of Australia records common names of the plant included "shingle oak," "coast she-oak," " river oak," " salt-water swamp oak" and was called "worgnal" by the indigenous people of the Richmond and Clarence River areas of New South Wales. It also records that, "In cases of severe thirst, great relief may be obtained from chewing the foliage of this and other species, which, being of an acid nature, produces a flow of saliva — a fact well-known to bushmen who have traversed waterless portions of the country. This acid is closely allied to citric acid, and may prove identical with it. Children chew the young cones, which they call 'oak apples'."

Distribution and habitat

Allocasuarina verticillata usually grows in grassy woodland, sometimes forming pure stands and sometimes with eucalypts. It is also found on rocky sea coasts and on dry ridges inland. In New South Wales it occurs on rocky hills south from Cobar and on coastal shale south from Sydney. It is widespread in Victoria, extending westwards to the Flinders Ranges, Gawler Ranges, western Eyre Peninsula and Kangaroo Island in South Australia. In Tasmania, the species is found near Launceston and on the east coast as far south Hobart and the Tasman Peninsula.

Uses

Aboriginal Australians make use of the tree for a range of tasks. The Ngunnawal people make tools including boomerangs from the tree's timber. Mature cones are used as children's toys.

Ecology

On Kangaroo Island, A. verticillata is the preferred food of the glossy black cockatoo, which holds the cones in its foot and shreds them with its powerful bill before removing the seeds with its tongue.

Biochemistry

Pedunculagin, casuarictin, strictinin, casuarinin and casuariin are ellagitannins have been found in this species.

Gallery

• Penultimate woody branchlets

  Penultimate woody branchlets

• Photosynthetic stems (phylloclades)

  Photosynthetic stems (phylloclades)

• Female inflorescence

  Female inflorescence

• Female inflorescence and cones developing on inner branches

  Female inflorescence and cones developing on inner branches

• Mature cone

  Mature cone

External links

• Occurrence data for Allocasuarina verticillata from The Australasian Virtual Herbarium