Inside a Plexiglas case is a small tree whose family roots date back to the age of the dinosaurs. The U.S. Botanic Garden is giving the three-year-old Wollemi Pine - which stands about half a meter high - a protected start in life.

"This exhibit is really all about the excitement about finding something brand new," says Christine Flanagan, spokeswoman for the U.S. Botanic Garden. "Suddenly we have a living fossil of which the last known living populations were 90 million years ago. "

The Garden is cultivating the Wollemi under a trial program with the Royal Botanic Gardens and North South Wales National Parks and Wildlife Service in Australia.

"This tree provides us a window on all of the evolution of an entire plant family that we don't know that much about," Ms. Flanagan says. "In its genes is the story of how it survived from the Jurassic until today."

The Wollemi Pine was discovered ten years ago by a park ranger and avid bushwalker in a remote wilderness area near Sydney. John Benson, senior ecologist at the Royal Botanic Gardens in Sydney, monitors the hidden grove of about 100 Wollemi. He says the conifer-like pine is a new genus in the 200 million-year-old Araucariaceae family.

"It grows up to about 40 meters high and up to about 1 meter in diameter," he says. "It has got a very unusual bubbly chocolate colored bark that I have never seen on another tree species anywhere. It has different type of foliage from the juvenile stage to the adult stage. The juvenile stage, the leaves look a little bit ferny. As the tree grows the leaves change and become too hardened, more spiky looking leaflets."

The location among steep canyons in Wollemi National Park remains a secret. The park wants to keep curious hikers - who might trample the trees or bring in disease on their boots - away.

John Benson says the Royal Botanic Gardens and the New South Wales National Parks and Wildlife Service are behind an effort to conserve the tree through propagation. They are working with test gardens in Australia and elsewhere around the globe.

"They have found out things like they can withstand temperatures from minus 5 [degrees Celsius] to plus 45 [degrees Celsius] as long as it has got water," says John Benson. "It can withstand a little bit of frost. It certainly would be a suitable potted plant for the northern part of America and Europe and Japan, and it would grow in gardens in the mid-latitudes fairly easily. And, they have found that it grows in a wide variety of soils as well."

He says working with the tree is like going back to the days of the dinosaurs. "I feel that I am basically back in the Jurassic period, which ran from about 200 million years ago to 65 million years ago," he says. "I feel that I am not on this earth. It is a relic that has hung on there. It didn't want to go extinct. It somehow survived ice ages and drought and fire. And just going back and looking at what things must have been like 50 million years ago!"

On the other side of the world visitors to the U.S. Botanic Garden in Washington are getting some sense of that history as they stare at the Wollemi in the plexiglass case.

"I think that it is very cool that it is that ancient of a tree, the fact that it has been around that long," one recent visitor commented. Another added, "I was just thinking how many species are going extinct without us even knowing that they existed. And, this is obviously one that I did not know existed."

The Royal Botanic Gardens in Sydney is expected to release the propagated plants for sale in October. The money raised will be dedicated to projects that safeguard the Wollemi Pine and other rare and endangered species.