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''Athrotaxis'' is a genus of two to three species (depending on taxonomic opinion) of conifers in the cypress family, Cupressaceae. The genus is endemic to western Tasmania, where they grow in high altitude temperate rainforests.〔Farjon, A. (2005). ''Monograph of Cupressaceae and Sciadopitys''. Royal Botanic Gardens, Kew. ISBN 1-84246-068-4〕〔Australian Plant Names Index: (''Athrotaxis'' )〕 They are medium-sized evergreen trees, reaching 10–30 m (rarely 40 m) tall and 1-1.5 m trunk diameter. The leaves are scale-like, 3–14 mm long, are borne spirally on the shoots. The cones are globose to oval, 1–3 cm diameter, with 15-35 scales, each scale with 3-6 seeds; they are mature in 7–9 months after pollination, when they open to release the seeds. The male (pollen) cones are small, and shed their pollen in early spring.〔 They are very susceptible to bush fires, and have declined markedly in abundance due to accidental and deliberate fires since the European colonisation of Tasmania.〔 ==Species== The three taxa of ''Athrotaxis'' are variously treated as three distinct species, or as two species, with the third taxon being a hybrid between the other two. To date, the evidence has been inconclusive, with some data suggesting hybrid origin, but other evidence suggesting the third is distinct and not a hybrid.〔 *''Athrotaxis cupressoides'' D.Don. Leaves short, 3–5 mm, adpressed tightly on the shoots. Cones small, 1-1.5 cm, scales with a small bract only covering the centre of the scale. *''Athrotaxis selaginoides'' D.Don. Leaves long, 8–14 mm, spreading out from the shoots. Cones large, 2–3 cm, scales with a large bract nearly completely covering the scale. *''Athrotaxis laxifolia'' Hook. (? ''A. cupressoides'' × ''A. selaginoides''). Leaves short, 4–7 mm, spreading out from the shoots. Cones intermediate, 1.5-2.5 cm, scales with a medium bract covering most of the scale. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Athrotaxis」の詳細全文を読む スポンサード リンク
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