Wollemia

Wollemia is a genus of coniferous tree in the family Araucariaceae. Wollemia was only known through fossil records until the Australian species Wollemia nobilis was discovered in 1994 in a temperate rainforest wilderness area of the Wollemi National Park in New South Wales, in a remote series of narrow, steep-sided sandstone gorges 150 km north-west of Sydney. The genus is named for the National Park. In both botanical and popular literature the tree has been almost universally referred to as the Wollemi pine, although it is not a true pine (genus Pinus) nor a member of the pine family (Pinaceae), but, rather, is related to Agathis and Araucaria in the family Araucariaceae. The oldest fossil of the Wollemi tree has been dated to 200 million years ago. The Wollemi pine is classified as critically endangered (CR) on the IUCN's Red List, and is legally protected in Australia. A Recovery Plan has been drawn up, outlining strategies for the management of this fragile population; the overall objective is to ensure that this species remains viable in the long term. Wollemia nobilis is an evergreen tree reaching 25–40 m (82–131 ft) tall. The bark is very distinctive, dark brown and knobbly, quoted as resembling Coco Pops breakfast cereal. The tree coppices readily, and most specimens are multiple-trunked or appear as clumps of trunks thought to derive from old coppice growth, with some consisting of up to 100 stems of differing sizes. The branching is unusual in that nearly all 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 when the cone becomes 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, which 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. As the leaves mature, they develop from bright lime-green to a more yellowish-green. The seed cones are green, 6–12 cm long and 5–10 cm in diameter, and mature about 18–20 months after wind pollination. They disintegrate at maturity to release the seeds which are small and brown, thin and papery with a wing around the edge to aid wind-dispersal. The male (pollen) cones are slender conic, 5–11 cm long and 1–2 cm broad and reddish-brown in colour and are lower on the tree than the seed cones. Seedlings appear to be slow-growing and mature trees are extremely long-lived; some of the older individuals today are estimated to be between 500 and 1,000 years old. The discovery, on or about 10 September 1994, by David Noble, Michael Casteleyn and Tony Zimmerman, only occurred because the group had been systematically exploring the area looking for new canyons. Noble had good botanical knowledge, and quickly recognised the trees as unusual because of the unique bark and worthy of further investigation. He took specimens to work for identification, expecting someone to be able to identify the plants. National Parks then went under a veil of secrecy, with the discoverers not learning the full magnitude of their discovery for about six months. National Parks came close to damaging the stand when a helicopter being used to collect cones inadvertently pruned one of the pines with its rotor. The species was subsequently named after Dave. The other members of the discovery party questioned the naming but were informed that nobilis referred to the trees being noble in structure and not to David Noble. The first illustrations of the Wollemi Pine were done by David Mackay, a botanical artist and scientific illustrator who was working at the Royal Botanic Gardens in Sydney when the species was discovered. Further study would be needed to establish its relationship to other conifers. The initial suspicion was that it had certain characteristics of the 200-million-year-old family Araucariaceae, but was not similar to any living species in the family. Comparison with living and fossilised Araucariaceae proved that it was a member of that family, and it has been placed into a new genus with Agathis and Araucaria.