Stress tests for trees

Scientists in Europe are working to determine which types of trees are likely to thrive in the region as climate change alters growing conditions.

As part of a 4-billion-euro ($5.2 billion) project called Reinforce, scientists planted 30 different species of trees from around the world at 37 sites along Europe's Atlantic coast to see where different types of trees thrive.

The Westonbirt Arboretum, Britain's national arboretum, set off about three hectares of land for three trial plots.

"In each plot there's new species of trees that will hopefully replace existing forestry crops in Britain," said Westonbirt's Raef Johnson.

The trees will only reach maturity in several decades time, so Reinforce's study won't reap immediate rewards. During that period, researchers in each of the participating sites will monitor and share data on the trees' size, general health and the timing of key events such as when their buds appear.

Monoculture forests

Policies in the UK, as well as other European countries, led to the spread of monoculture tree planting, which has left forests vulnerable to a changing climate as well as disease, according to Rupert Pigot, head of policy at Confor, which promotes forestry in the UK.

"The way that we grow our trees here in the UK means that we do rely very heavily on certain species," he said. "The current issue we have is a disease called phytophora remorum which is affecting Japanese larch. There are large swathes of larch down in the southeast, and going up through Wales and on the west coast of Scotland which are being affected by this."

As it imports most of its timber, there is no need for the UK to examine alternative sources of wood at the moment, according to John White from the Timber Trade Federation.

"People will always be looking at sources of supply and the properties of the material that they use, and, of course, for foresters the planning process is over the longer term," he said. "But it's so difficult to be predicting what will be happening over the next hundred years or so, especially with seemingly rapid change in climate."

Looking to the future

Keeping an eye on industry's future needs, however, is what projects like Reinforce need to focus on, according to Confor's Jane Karthaus, who added that industrial groups should also consider how their work could change over the next few decades.

"To a certain extent, the markets will appear for what we are producing," Karthaus said. "I just perhaps have a slight concern: we need to do this in a joined up way, not go in total isolation."

For Mark Ballard, head curator at Westonbirt, the Reinforce project needs to go beyond ensuring timber supplies for the future. The scheme is a reminder, he said, of people's duty as stewards of nature.

"One by one these trees are being affected by different pests and diseases," he said. "We need to look at alternatives, and we need to spread the risk. It's just about being responsible managers."

Author: Robin Powell / sms
Editor: Nathan Witkop