The Wollemi pine was discovered in 1994 in the Wollemi National Park, 150 kilometres from Sydney, Australia. It was previously known only from fossils, and the entire known wild population consists of less than 100 trees, spread between 3 groups – the locations of which are kept strictly secret. The species has baffled geneticists – as it appears that there is no genetic diversity within living specimens.
Discovery of the dinosaur plant:
The Wollemi pine was discovered by David Noble, a NSW National Parks and Wildlife Officer. Noble is an avid bushwalker and abseiler, and noticed the unusual plant when hiking with friends. He took a branch back to be identified, and caused frenzied interest when he stated that the fern-like foliage had come from a 40 metre high tree. A team of botanists tracked down the pine’s ancestry. The Wollemi pine is the only species extant in its genus. The genus was named after its location – the Wollemi National Park. The species name “nobilis” reflects both the majestic nature of the tree, and the name of its discoverer. “Wollemi” is an Aboriginal word – it seems apt that its meaning is "look around you, keep your eyes open and watch out". Had David Noble not kept his eyes open – we might have continued with this amazing plant unknown to us, right on our doorstep.
The fossil pine:
Fossil remains of members of the genus Wollemia can be found throughout Australia, New Zealand and Antarctica. The earliest known fossil record of the genus is 90 million years old, and the latest is from 2 million years ago. The genus was thought to have become extinct around that era. The Araucariaceae family became extinct in the northern hemisphere during the end of the Cretaceous period, and until the mid Tertiary period, plants of the Araucariaceae thrived on the southern super-continent Gondwana. The flowering plants gradually displaced conifers, and the only known living relatives of the Wollemi are its Araucariaceae cousins – the Agathis genus (the Kauri pine) and the Araucaria genus (Norfolk Island pine, Hoop pine, Bunya Bunya and Monkey Puzzle pines). Research is still continuing, attempting to track the Wollemi through time.
The Wollemi Pine is an extremely unusual tree. The tree grows to about 40 metres high and can have trunks up to 1 metre in diameter. Its bark resembles coco-pops, and it has fern like foliage. The leaves (not needles) are not stalked, but in fact are attached most of the way around the branch. Whole branches are shed, as opposed to individual leaves. The leaves have very thick cuticles, and sunken pores, helping to reduce water loss. The juvenile leaves are bright lime green, whereas the adult leaves are a deeper, dull blue green. Along the branch, the leaf pattern looks rather undulating, as the leaves do not grow as long at the beginning and end of the growing period. Male and female cones are produced, and form at the end of branches.
Branches form in two types – upright branches that form another stem or trunk, and sideways branches, which bear foliage. The tree thus develops a branched crown. The Wollemi characteristically forms coppices – due to the formation of upright branches from the base of the tree. As the coppiced trunks move apart, they form what appears to be a separate tree. The original trunk may die, but the organism lives on. It is thus impossible to accurately gauge the age of a Wollemi by counting the rings in the trunk (with fallen trunks only, naturally), as this only ascertains the age of that particular trunk, not of the organism itself. It is believed that one of the trees in the original population, known as “King Billy” may have a root system that dates back over 1000 years.
The Wollemi favours slightly acid soils,temperatures from 0 - 40°C (though it can withstand temperatures of -5°C), and is relatively fast growing given sufficient light. The cuttings and seedlings currently being propagated are growing at a rate of around 0.5 metres per year.
Genetic diversity in the Wollemi pine:
Bluntly put – there isn’t any. The preliminary research into the first population found no genetic diversity. More detailed research into two of the populations still failed to find any variation in the genetic structure of the plants. Research continues, using different methods.
This was, to say the least, unexpected. It was suggested that the 38 adults at the original site were in fact the same organism – having coppiced, with the trunks slowly growing apart. Finding the second population to be (as far as can be ascertained so far) genetically identical to the first, it was postulated that perhaps the plants can produce seeds that are exact clones. Another possibility is that the sheer length of time that the species has been extant has allowed it to reach a kind of evolutionary pinnacle. Or populations could have sunk to even lower than they are now – forming an evolutionary “bottleneck”: wiping out most of the individuals and leaving only a tiny genetic stock to propagate itself. Dr. Rod Peakall, of the Australian National University Botany and Zoology department, is the leader of the team performing genetic studies on the Wollemi. He has begun studying the other Araucariaceae species, hoping to find some hint about the reason for the Wollemi’s apparent clones. Preliminary studies into the Agathis species show very little genetic variation, though there is some.
If the entire Araucariaceae family has low genetic variability, this will assist researchers greatly. Previously it has been a widely held belief that genetic diversity is essential for the longevity of a species – to help it withstand disease, fire, and other threats. The Wollemi pine discoveries could well prove an exception to the rule, or even the evidence that debunks a myth.
For some time researchers were concerned at the lack of Wollemi seedlings – but seedlings were found in 1995 and 2000 with the discovery of the second and third populations. However, the seedlings are also genetically identical to the adult stock. Basically – it’s all a big mystery.
Protecting the pine:
The locations of the three Wollemi pine populations are kept strictly secret. Only researchers with a real need to visit the site are allowed in. (To illustrate the extreme limits on visitors: in 1997 when I was attending lectures by Rod Peakall – the geneticist in charge of decoding the tree’s DNA – he had not been given permission to visit the site). People who do visit the site must disinfect their shoes before abseiling in – to prevent weeds, or fungi and other pathogens, from entering the site.
The Wollemi pine has been listed under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 as well as the NSW Threatened Species Conservation Act 1995.
In order to prevent avid collectors from trying to find the site, a propagation plan was developed as soon as the pine was identified. It is now possible to own your very own Wollemi pine. They can be grown indoors or outdoors, but outdoors varieties would need a fair bit of space…they’ll eventually grow pretty big. The first Wollemis sold at Sothebys - with 292 trees fetching around AU$1 million. Now, you can get a small one for around $60. Royalties from the sales will fund further research and protection.
Watching the Wollemi:
You can see young Wollemi pines at the following places:
Notes from lectures by Dr. Rod Peakall, 1997.