Swedish researchers find world's oldest living tree

Yahoo News 17 Apr 08;

The world's oldest living tree on record is a nearly 10,000 year-old spruce that has been discovered in central Sweden, Umeaa University said on Thursday.

Researchers had discovered a spruce with genetic material dating back 9,550 years in the Fulu mountain in Dalarna, according to Leif Kullmann, a professor of Physical Geography at the university in northwestern Sweden.

That would mean it had taken root in roughly the year 7,542 BC.

"It was a big surprise because we thought until (now) that this kind of spruce grew much later in those regions," he said.

Scientists had previously believed the world's oldest trees were 4,000 to 5,000 year-old pine trees found in North America.

The new record-breaking tree was discovered in Dalarna in 2004 when Swedish researchers were carrying out a census of tree species in the region, Kullman said.

The tree's genetic material age had been calculated using carbon dating at a laboratory in Miami, Florida.

Spruces, which according to Kullmann offer rich insight into climate change, had long been regarded as relatively newcomers in the Swedish mountain region.

The discovery of the ancient tree had therefore led to "a big change in our way of thinking," he said.

World's oldest tree discovered in Sweden
Roger Highfield, Science Editor The Telegraph 17 Apr 08;

The world's oldest tree has been found in Sweden, a tenacious spruce that first took root just after the end of the last ice age, more than 9,500 years ago.

The tree has rewritten the history of the climate in the region, revealing that it was much warmer at that time and the ice had disappeared earlier than thought.

Previously, pine trees in North America were thought to be the oldest, at around 5,000 years old.

But Swedish scientists report that in the mountains, from Lapland in the north to Dalarna in central Sweden, there are much more ancient spruce trees (Picea abies).

Prof Leif Kullman at Umeå University and colleagues found a cluster of around 20 spruces that are over 8,000 years old.

The oldest tree, in Fulu Mountain, Dalarna (“the dales”), was dated by carbon dating at a laboratory in Miami, Florida to 9,550 years old and underneath the crown in the soil there were another three generations of wood from the same clone, dating 375, 5,660 and 9,000 years old that have the same genetic makeup.

The clones take root each winter as snow pushes low lying branches of the mother tree down to ground level, explains Prof Kullman.

“A new erect stem emerges, and it may lose contact with the mother tree over time.”

The trunks of the mother tree would survive only around 600 years but the trees are able to grow a new one, he adds.

The finding is surprising because the spruce tree has been regarded as a relative newcomer in the Swedish mountain region and is thought to have originated 600 miles away in the east.

"Our results migration in the complete opposite direction has be considered, because the spruce is one of the oldest known trees in the mountain range,” says Prof Kullman.

Ten millennia ago, a spruce would have been extremely rare and it is conceivable that the ancient humans who lived there imported the tree, he says.

“Man immigrated close to the receding ice front. We have also found fossil acorns in this area, and people may have taken them with them as they moved over the landscape.”

It had been thought that this region was still in the grip of the ice age but the tree shows it was much warmer, even than today, he says.

“Spruces are the species that can best give us insight about climate change,” he says.

The summers 9,500 years ago were warmer than today, though there has been a rapid recent rise as a result of climate change that means modern climate is rapidly catching up.

The tree probably survived as a result of several factors: the generally cold and dry climate, few forest fires and relatively few humans.

Today, however, the nature conservancy authorities are considering putting a fence around the record breaking tree to protect it from trophy hunters.