Bathed in a violet glow, John Siemon strides into the cool room of the concrete bunker, pulling on gloves and a thick jacket - an occupational necessity at the PlantBank.
Behind the glass windows are three vaults storing 100 million seeds in temperatures ranging between four to minus 20 degrees.
Siemon, the PlantBank's project manager, takes out one of the trays of small foil packets. Each one is carefully numbered and linked to other DNA related samples in the collection.
Inside the bunker a fifth of Australia's 25,000 plant species are represented, including 260 of NSW's rare and endangered species. An insurance policy, if you like, against possible extinction, allowing future scientists to bring back to life native plants for regrowth or medical research.
'We've shifted our science from behind our barbed wire fence to a place where the public can come in and see our science and conservation activities.'
Australia has 14 per cent of the world's threatened plant species with 611 species on the endangered list in NSW alone.
"We can store our seeds for several hundred years and for our longer lived seeds our scientists suggest maybe even several thousand years," says Siemon. "This buys us more time for scientists to analyse a plants chemical make-up."
Some of the seeds will certainly outlive the new architecturally designed PlantBank building.
The PlantBank is Australia's first line of defence in plant conservation and the new building at the Australian Botanic Garden at Mount Annan is designed to safeguard the future of our native flora. Built at a cost of $19.8 million it can withstand four hours of bushfire, using concrete and stainless steel to reflect the heat and minimise risk to the seed collection. In the event of fire, protective screens will also slide down over the glass, preventing embers from entering the building.
The vault is protected by a concrete shell inside the building. But not all seeds make it to the vault. Some, due to their moisture content, will be stored cryogenically, in trays on a type of lazy susan, in temperatures as low as minus 196 degrees. About half of all rainforest species in Australia fit into that category, with plant cells and tissue stored in liquid nitrogen in the PlantBank's new $600,000 vat-like storage facility.
The surrounding landscape is designed to blend into the building's interior and exterior, using the biodiversity of the endangered Cumberland Plain Woodland located just north of the building.
The new PlantBank, which was completed in October last year, is now open to the public. Visitors can view scientists at work as they sift, clean, dry, test and prepare the seeds for storage.
"We've shifted our science from behind our barbed wire fence to a place where the public can come in and see our science and conservation activities," says Siemon.
Austinmer's Graeme Errington has just returned from south-east Asia where he was part of a PlantBank team assisting Vietnamese horticulturalists on how to manage and construct their own botanic gardens and protect their native flora. It is an outreach program aimed at greater conservation of plant species.
Errington sits in a sandstone garden bed under the new building, a link to the past when Australia's first botanists began to collect and sow seeds in the Royal Botanic Garden in Sydney almost 200 years ago.
"We're trying to grow lichen on the sandstone, but it's not working out too well," says Errington. "Lichen grows easily on any wall you don't want it to grow on. It can be frustrating at times."
It's encouraging to hear that even the experts can have their bad days in the garden.
Some of the seeds collected by early botanists dating back 150 years are on display in the foyer of the PlantBank. They sit in small brown glass jars, just above the world's largest seed, the 17.6 kg Coco de Mer, or Sea Coconut, a palm endemic in the Seychelles. The smallest seed in the world is, in comparison, a tiny speck of dust belonging to an orchid.
Errington is a seedbank officer on the PlantBank's Rainforest Project.
"The idea of seed storage is to dry the seed down to a very low moisture content and then freeze them," explains Errington. "But only 50 per cent of rainforest plants can be treated that way. My role is to go out collect the seed, examine it, test it and determine how it will be treated."
Rainforest seeds and their embryo is a new area of research.
"It's ripe for the picking," says Errington. "There's a lot to learn, that's for sure. When you're presented with a challenge there's no one else to ask. You have to work it out yourself. It can be a complex process. Seeds don't grow themselves. We need techniques for taking the seeds or part of the seed and turning it back into whole plants. We can actually dissect out the embryo which contains all of the genetic information of the plant, discard the rest of the seed and using a sterile environment we can regrow any part of the plant."
Plants are under threat from human development, climate change, disease and natural disasters.
"The moment we have lost a plant we can never get it back," warns Siemon. "We need to think of the Australian PlantBank as being an insurance policy. The seed sits there, in case the species becomes extinct, until we're ready to to learn about the plant material. At least then we have the option to go back in time."
A duplicate set of the seeds is also sent to the United Kingdom to be stored in an underground vault in the Millennium Plant Bank.
"If our collection is destroyed then there's a back up," says Siemon. "It's going to take us a long time to work out each plant's potential. Our goal is to keep snapshots of a plant's genetic material. In the future scientists may find many pharmaceutical and medical products, food or alternative fibres. When a plant becomes extinct we might be missing a cure to cancer or fail to find products that regulate certain bodily functions."
Siemon says many medical advancements have come from the study of the compounds within plants.
"There are a lot of products that people take on a day-to-day basis that are actually originally derived from plants," he says. "The contraceptive pill is made from a product within yams and the digitalis foxglove plant has chemicals that can be used to regulate the heart beat."
The PlantBank is also working with other agencies to combat the spread of the disease myrtle rust which snuck into the country from Brazil, possibly via Hawaii, almost three years ago.
In a short time it has spread across the eastern seaboard of Australia from Cairns to Melbourne.
The disease is so widespread that it's now impossible for authorities to eradicate.
Myrtle rust attacks the myrtaceae family which represents nearly 16 per cent of Australia's flora, including many of Australia's iconic plants such as eucalypt, bottle brushes and lilly pillies.
"Its a sizeable disease that has the potential to destroy a lot of plants," explains Siemon.
"Disease symptoms can be total defoliation of a tree and death to all seedlings.
"It's quite extreme and we are yet to know its full potential damage to our native flora but we are pretty sure that several species will be made extinct. "
Free weekend tours are available of the PlantBank between 11am and 1pm. Some weekday tours are also available.
Visitors are advised to contact 46 347935 to confirm tour times.