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Wollemia is a genus of coniferous trees in the family Araucariaceae, endemic to Australia. It represents one of only three living genera in the family, alongside Araucaria and Agathis (being more closely related to the latter). The genus has only a single known species, Wollemia nobilis, commonly known as the Wollemi pine (though it is not a true pine) which was discovered in 1994 in a temperate rainforest wilderness area of the Wollemi National Park in New South Wales. It was growing in a remote series of narrow, steep-sided, sandstone north-west of Sydney. The genus is named after the National Park.
The Wollemi pine is classified as critically endangered (CR) on the IUCN's Red List, and is legally protected in Australia. After it was discovered that the trees could be successfully cloned, new trees were potted up in the Botanic Gardens of Sydney and Mount Annan and planted as far away as the Humboldt Botanical Garden near Eureka, California and in a garden near the Malvern Hills in England, which was planted in 2010 and began producing cones in 2025.
A Recovery Plan has been drawn up, outlining strategies for the management of this fragile population. The overall objective is to ensure that the species remains viable in the long term. Australian prime ministers and foreign affairs ministers have presented Wollemi pines to various dignitaries around the world.
Although often described as a "living fossil", there are no unambiguous fossils of Wollemia and potential fossil records of it have been considered uncertain.
The leaf are flat linear, long and 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, long and in diameter, and mature about 18–20 months after wind pollination. They disintegrate at maturity to release the 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, long and 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.
He took specimens to work for identification, expecting someone to be able to identify the plants.
The first illustrations of the Wollemi Pine were drawn 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 Araucariaceae proved that it was a member of that family, and it has been placed into a new genus, beside the genera Agathis and Araucaria.
Fewer than 60 adult trees are known to be growing wild in four locations, not far apart. It is very difficult to count individuals, as most trees are multi-stemmed and may have a connected root system. Genetic testing has revealed that all the specimens are genetically indistinguishable, suggesting that the species has been through a genetic bottleneck 10,000–26,000 years ago, in which its population became so low (possibly just one or two individuals) that all genetic variability was lost.
The grove of Wollemia trees was endangered by fire during the 2019–2020 Australian bushfire season. They were saved by specialist firefighters from the National Parks and Wildlife Service, supported by the Rural Fire Service who installed an irrigation system as well as dropping fire retardant
Results were tallied from more than 1,500 people from 31 countries who were growing the cuttings and responded to an online survey created by two plant scientists in Australia. Results indicated that the species grows well where climate is temperate and there is adequate year-round rainfall. Loam with good drainage proved to be ideal. The team concluded, "This study demonstrates that it is feasible to establish Wollemi pines in many parts of the world and under different climates and cultural regimes, which can help conserve this species in the face of climate change and other threats."
The Royal Botanic Gardens in Sydney has published information on how to grow Wollemi pines from seed harvested by helicopters from the forest trees. The majority of seeds that fall from the cone are not viable so need to be sorted to retain the plump and dark ones. These can then be sown on top of seed raising mix and watered. Once the water has drained through the mix, the pot should be placed in a plastic bag and refrigerated for two weeks. After this, the pot should be removed from the plastic bag and placed somewhere warm but not very sunny until the seed germinates (remembering to keep them moist but not wet). This could take several months.
Examples of the species can be viewed at The Tasmanian Arboretum, at Giardini di Villa della Pergola in Alassio, Italy, and at the Humboldt Botanical Gardens near Eureka, California.Wilbur, Mary. "Pacific Horticulture | Humboldt Botanical Gardens". Pacific Horticulture. Retrieved November 13, 2024.
Scrutiny of the fossil record likewise does not clarify Wollemia relationship to Araucaria or Agathis, since the former has similarly disparate leaf characters in its adult and juvenile forms, and the latter has similar cone characters.
Further, the recent description of several extinct genera within the Araucariaceae points to complex relationships within the family and a significant loss of diversity since the Cretaceous.
An early study of the rbcL gene sequence places Wollemia in the basal position of the Araucariaceae and as the sister group to Agathis and Araucaria.
In contrast, another study of the rbcL sequence shows that Wollemia is the sister group to Agathis, and Araucaria is basal. The different outgroup selection and genes used in previous studies are the reasons behind the discrepancy over the groupings of the three genera.
Later genetic studies corroborate Wollemia
a combination of rbcL and Maturase K genes,
and a comprehensive study encompassing nuclear ribosomal 18S and 26S rRNA, chloroplast 16S rRNA, rbcL, matK and rps4, and mitochondrial coxl and atp1 genes.
Below is the phylogeny of the Araucariaceae based on the consensus from the most recent Cladistics of molecular data. It shows the relative positions of Wollemia, Agathis, and Araucaria within the division.
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