Athrotaxis laxifolia

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Athrotaxis laxifolia
Athrotaxis laxifolia.jpg

Athrotaxis laxifolia

Systematics
Class : Coniferopsida
Order : Conifers (Coniferales)
Family : Cypress family (Cupressaceae)
Subfamily : Athrotaxidoideae
Genre : Scaled spruce ( athrotaxis )
Type : Athrotaxis laxifolia
Scientific name
Athrotaxis laxifolia
Hook.

Athrotaxis laxifolia is a conifer of the genus of athrotaxis ( Athrotaxis ) in the family of cypress plants (Cupressaceae). The evergreen tree isnativeto Tasmania .

description

Branch with leaves and cones

Athrotaxis laxifolia is an evergreen tree . It forms a conical, loosely branched tree crown and reaches heights of 12 to 21 m. The bark of the trunk is dark orange-brown with deep cracks and comes off in scales. The branches of the fresh shoot are pale to light yellow. The leaves are ovate to lanceolate. They are arranged in a spiral, about 6 mm long and tapering to a point. There are two ostomy straps on the top. The leaf margin is entire and translucent.

Athrotaxis laxifolia is monoecious ( monoecious ). The male cones form two pollen sacs per microsporophyll. The female cones are at the ends of short shoots. They are oriented downwards both at flowering time and at maturity. Ripe cones are about 1.8 cm long. They are brown, oblong ovoid and have cone scales triangular in shape. At the upper end of the cone scales on the back there is a small spinous process. Cover and seed scale have grown together to form the cone scale. The seeds have narrow wings on both sides and are spread out by the wind.

The wood of the Athrotaxis laxifolia is soft and pale reddish. It is not used commercially as the occurrences are insignificant and the trees are often solitary.

Occurrence

Athrotaxis laxifolia (or hybrid, see chapter Systematics) is endemic in Tasmania . It thrives in mountain rainforests at altitudes from 900 to 1200 m above sea level. NN in the western to central part of the island.

Systematics

The first description of Athrotaxis laxifolia was made in 1843 by the British botanist William Jackson Hooker . A synonym for Athrotaxis laxifolia Hook. is athrotaxis doniana Henk. & Hochst.

According to Isoda et al. In 2000 it is disputed whether it is a separate species or whether Athrotaxis laxifolia is a hybrid of the two species Athrotaxis cupressoides and Athrotaxis selaginoides . This assumption is supported by the fact that the occurrence is limited to the common distribution area of ​​these two species and that the foliage between these two species has characteristics. According to a publication from the year 2000, evidence of the hybrid property was provided by DNA analysis.

literature

  • K. Isoda, TJ Brodribb, S. Shiraishi: Hybrid origin of Athrotaxis laxifolia (Taxodiaceae) confirmed by random amplified polymorphic DNA analysis . In: Australian Journal of Botany . tape 48 , no. 6 , 2000, ISSN  0067-1924 , p. 753-758 , doi : 10.1071 / BT99032 .

swell

  • Christopher J. Earle: Athrotaxis laxifolia. In: The Gymnosperm Database. December 12, 2010, accessed October 20, 2011 .

Individual evidence

  1. ↑ Armin Jagel, Veit Martin Dörken: The cones of the cypress family (Cupressaceae) - Part 1: Subfamilies Cunninghamioideae, Athrotaxoideae, Taiwanioideae, Sequoioideae, Taxodioideae. Communications from the German Dendrological Society, Vol. 100, 2015, pp. 161–176.
  2. ↑ a b Armin Jagel, Thomas Stützel: Cypress plants (Cupressaceae sl) in the Palmengarten Frankfurt (Part II) - the representatives of New Zealand and Australia: Libocedrus plumosa, Libocedrus bidwillii and Athrotaxis laxifolia. Palmengarten, Vol. 65, 2001, pp. 22-27.
  3. ↑ William Jackson Hooker: Icones Plantarum . tape 6 , 1843 (plate 573).
  4. ↑ K. Isoda, TJ Brodribb, S. Shiraishi: Hybrid origin of Athrotaxis laxifolia (Taxodiaceae) confirmed by random amplified polymorphic DNA analysis . In: Australian Journal of Botany . tape 48 , no. 6 , 2000, ISSN  0067-1924 , p. 753-758 , doi : 10.1071 / BT99032 .

Web links

Commons : Athrotaxis laxifolia  - collection of images