Forest geneticists aim to tune up Canada’s working forests with trees better suited to changing climate conditions and that increase timber yields by up to 30 per cent in the bargain.
The $5.8-million project won’t be creating genetically engineered trees, rather the researchers will scour the genes of diverse existing populations of important species such as Douglas fir and lodgepole pine for useful and often highly localized adaptations to heat, cold, drought, snow and rain.
“Trees of the same species from warm places tend to grow longer and faster than trees from colder places, but they might be less cold hardy,” said lead researcher Sally Aitken, a forestry professor at the University of British Columbia. “So there is significant genetic variation between a larch from one place and another.”
The CoAdapTree project will identify trees with patterns of traits better adapted to areas where existing tree populations are struggling because of climate change.
“Better matching trees with new climates will improve the health and productivity of planted forests,” she said, adding the new approach using genomics and seedling trials will yield answers within a few years.
The strategy is a departure from traditional thinking, going back centuries, which held that the local populations of trees would be best adapted to their immediate environment. Based on that thinking, the seeds used to grow trees for reforestation would be gathered from local tree populations, grown and returned to the same area.
No more.
Trees in any specific region tend to be adapted to the historical climate of that region. But as climate changes, the comfort zones for tree populations are moving north or to higher elevations, forcing the trees to chase the cooler or wetter conditions they prefer, said Aitken.
But the comfort zones are changing much faster than tree populations can adapt.
“The fastest that a tree species can migrate is no more 100 to 200 metres per year,” she said. “Climate is moving several kilometres a year. My colleagues at the University of Calgary estimate that trees are lagging 130 kilometres behind their optimal climate already.”
The researchers hope to apply their findings to the planted forest, which provides hundreds of thousands of jobs and contributes $20 billion to Canada’s economy.
“We plant about 250 million trees a year in this province and that number is about to rise, so if we are going to all that trouble and expense, we should be trying to plant the right trees in the right places,” Aitken said.
The coming carnage in B.C.’s natural forests makes getting reforestation right all the more urgent.
“The managed land base of B.C. is just over one third of our area, so all those areas that we don’t manage, where we don’t plant trees, nature will take its course,” she said. “Forests are resilient and they will adapt, but it’s going to take generations and there will be a lot of mortality in the interim.”
“In the meantime, (the natural forests) will not be storing as much carbon nor providing all the ecological services that we are used to while they endure an unhealthy state,” she said.
Funding for CoAdapTree is provided by the B.C. Ministry of Forests, Genome Canada, Genome B.C. and Natural Resources Canada, among others.