Wollemia
|
|
| Wollemia Conservation status: Critical | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Missing image WollemiPine.JPG Young specimen in a botanical garden protected from theft by a steel cage | ||||||||||||||
| Scientific classification | ||||||||||||||
|
Wollemia nobilis is a remarkable coniferous tree that was discovered in 1994 in a remote series of narrow, steep-sided sandstone gorges in a mild temperate-zone rainforest wilderness area of the Wollemi National Park in New South Wales, 150 km north-west of the Australian city of Sydney.
In popular literature, the tree has been named "Wollemi Pine", though this is a misnomer, as it is not a pine.
The discovery, by David Noble, a field officer of the Wollemi National Park in the Blue Mountains, only occurred because of his adventurous bushwalking and rock climbing abilities. Luckily, he had good botanical knowledge and quickly recognised the trees as unusual and worthy of further investigation. Noble returned with specimens that he expected someone would be able to identify. However, it was soon found to be new to science. Further study would be needed to establish its relationship to other conifers. All that was at first suspected by the botanists was that it had certain characteristics of the 200-million-year-old family Araucariaceae, but was not the same as any living species in the family.
Wollemia is an evergreen tree reaching 25-40 m tall. The bark is very distinctive, dark brown and knobbly, quoted as resembling chocolate-coated Rice Krispies. The tree coppices readily, and most specimens comprise multi-trunk clumps of trunks thought to derive from old coppice growth. The branching is unique in that nearly all of the side branches never have further branching; after a few years, each branch either terminates in a cone (either male or female) or ceases growth; after this or the cone is mature, the branch dies. New branches then arise from dormant buds on the main trunk. Rarely, a side branch will turn erect and develop into a secondary trunk, this then bears a new set of side branches.
The leaves are flat linear, 3-8 cm long and 2-5 mm broad; they are arranged spirally on the shoot but twisted at the base to appear in two or four flattened ranks. The seed cones are green, 6-12 cm long and 5-10 cm diameter, and mature in about 18-20 months after pollination; they disintegrate at maturity to release the seeds. The male (pollen) cones are slender conic, 5-11 cm long and 1-2 cm broad.
Comparison with living and fossilised Araucariaceae proved that it was a member of that family, and it was placed into a new genus with the other extant genera Agathis and Araucaria. Fossils resembling Wollemia and possibly related to it are widespread in Australia, New Zealand and Antarctica, but Wollemia nobilis is the sole living member of its genus.
Fewer than a hundred trees are known to be growing wild, in three localities not far apart. Genetic testing has revealed that all the specimens are genetically indistinguishable, suggesting that the species has been through a genetic bottleneck in which its population became so low (possibly just one or two individuals) that all genetic variability was lost.
Cultivation and uses
A propagation programme is underway with the first commercial release of this plant worldwide scheduled for 2006, with sales in Australia and elsewhere. It should prove itself to be a valuable tree for ornament, either planted in open ground or for tubs and planters. It is also proving itself to be more adaptable and cold-hardy than its restricted distribution would suggest, tolerating temperatures down to -5°C, with one unverified report of a young plant surviving a temperature of -12°C. Like many other Australian trees, Wollemia is susceptible to the root fungus Phytophthora, so this may limit its potential as a timber tree.
External links and references
- Sydney Royal Botanic Gardens website gives facts and figures, ecology, biology. (http://www.rbgsyd.gov.au/information_about_plants/wollemi_pine)
- Royal Botanic Gardens at Kew's web page about the "Wollemi Pine" (http://www.rbgkew.org.uk/plants/wollemipine.html)
- WollemiPine.com (http://wollemipine.com/)
- BBC News item (http://news.bbc.co.uk/1/hi/england/london/4531805.stm) 10 May 2005
- ABC-TV Science visits Wollemi Pines in the wild (http://www.abc.net.au/catalyst/stories/s1371627.htm) 19 May 2005
da:Wollemia nobilis de:Wollemia nobilis fr:Pin de Wollemi pl:Wollemia szlachetna