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. They are commonly known as Pencil pines.
The three taxa of Athrotaxis are variously treated as three distinct species, or as two species, with the third 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, 0.12 to 0.2 inch (3 – 5 mm), adpressed tightly on the shoots. Cones small, 0.4 to 0.6 inch (1 – 1.5 cm), scales with a small bract only covering the centre of the scale.
- Athrotaxis selaginoides (D.Don) Leaves long, 0.3 to 0.55 inch (8 – 14 mm), spreading out from the shoots. Cones large, ca. 1 inch (2 – 3 cm), scales with a large bract nearly completely covering the scale.
- Athrotaxis laxifolia (Hook) (? A. cupressoides × A. selaginoides). Leaves short, 0.16 to 0.28 inch (4 – 7 mm), spreading out from the shoots. Cones intermediate, less than 1 inch (1.5 – 2.5 cm), scales with a medium bract covering most of the scale.
Description. Pencil pines are medium-sized evergreen coniferous trees, growing to mature heights reaching 35 to 100 feet (10 – 30 m) (rarely to 125 feet/40 m) tall with a 3 to 5 foot (1 – 1.5 m) trunk diameter at breast height. The leaves are scale-like, 0.12 to 0.55 inch (3 – 14 mm) long, are borne spirally on the shoots. The cones are globose to oval, 0.4 to 1.2 inches (1 -3 cm) in diameter, with 15 to 35 scales, each scale with 3 to 6 seeds which mature 7 to 9 months after pollination, when they open to release the seeds. The 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 colonization of Tasmania.
The wood is scented and durable, and was extensively used in the past in Tasmania, but is now too rare for any cutting. All three make very attractive ornamental trees with luxuriant foliage, though they are generally only planted in arboretums or botanical gardens. Cultivation away from their native range is successful only in areas with high rainfall, mild winters, and cool summers, such as the British Isles, the Pacific Northwest of North America, and New Zealand.
Examples of the species and many of its leaf froms may be seen in the living collections at The Tasmanian Arboretum.Attributed from: Wikipedia