By Nelson Bennett
As the northern hemisphere experiences earlier, hotter, drier summers and heavier precipitation in the winters, due to global warming, natural selection should eventually result in trees naturally adapting to changing climatic conditions.
Tree varieties that thrive in warmer, drier southern parts of the province, or on lower slopes, are likely to gradually shift further north and further up mountain slopes.
Scientists and foresters in B.C. are already beginning to give them a gentle nudge through assisted migration – one of the topics this morning at the University of British Columbia’s ongoing three-day Commonwealth Forestry Conference.
Using a variety of scientific tools and experiments, like genomics and provenance trials, scientists have already been able to identify which tree varieties have naturally evolved certain traits, like cold hardiness, disease resistance and drought tolerance, in different geographic regions.
Climate data can be matched with tree phenotype data to identify which trees will be best suited to climate conditions in the coming decades. Genomics is an additional tool that helps scientists identify key genetic characteristics.
These tools are used to develop seed lots that foresters can use to replant trees in a given area that are the same species, but different varieties that have traits that make them more suitable to a climate that is changing rapidly.
Interior varieties of Douglas fir, for example, are more cold hardy than coastal varieties. And Sitka spruce from California grow longer and bigger than ones that grow in Alaska. They are the same species of tree, but are different varieties that have naturally adapted to their particular environments.
Scientists and foresters are already using these tools to identify which varieties might fare better in certain areas, and use them in what is called “assisted migration” using a climate-based seed transfer program.
To date, the climate based seed transfer program in B.C. has been optional, but will become mandatory next year, said Sally Aitken, a forestry scientist at UBC’s department of forest and conservation science.
By Brandon Barrett
Herb Hammond doesn’t quite fit the picture you probably have in mind of the typical forester.
A Dalai-Lama-quoting policy wonk, author and ecologist with 40 years experience in the industry, Hammond belies the clichéd image of forester as grizzled lumberman decked out in plaid.
But Hammond also defies the usual notion of forester in another significant way: He fervently believes B.C.’s forest management framework needs a complete overhaul—and urgently.
“Forestry causes the largest losses of biological diversity across this province, indeed virtually everywhere that it’s practised. It’s the primary cause of water degradation. It’s a major contributor to floods and droughts, and believe it or not, in B.C., it’s less than two-and-a-half per cent of the gross domestic product. That shows you the power of assumptions of convenience about what’s driving our economy. Certainly it’s not forestry,” he said. “Either we’re going to change this or we’re going to continue to down a path where Earth will change us.”
Hammond was the keynote speaker at an in-depth forestry webinar co-hosted last month by the Whistler Naturalists and the Association of Whistler Area Residents for the Environment, where he picked apart B.C.’s current forestry system, and laid out his vision for a new way of managing the province’s most vital asset that puts ecological integrity over industry profitability.
One of the most common notions put forth by the timber lobby is that old-growth forest, typically defined in B.C. as trees over the age of 250 on the coast, and 140 in the Interior, as a renewable resource. Not so, says local forest ecologist and Whistler Naturalists co-founder Bob Brett.
“Logging removes old forest from the landscape, and I think for all intents and purposes, we can say forever,” he relayed. “If you take out a forest that’s 300, 500, over 1,000 years old and then plant it like it has been planted at the higher elevations up in the Soo Valley, it will never in reasonable terms recover to being the old-growth forest it used to be. It’s going to be simpler, it’s going to have fewer species that require this old-forest habitat, and it will have fewer underground fungal connections. There are many reasons why it will never be the same forest again.”
While he acknowledges the legislation is by no means perfect. Hammond pointed to several landmark acts adopted south of the border as a potential example for B.C. to follow if we want to transform how forests are managed here.
In short, legislation like the U.S. Endangered Species Act, the National and Environmental Policy Act, which mandates ecological assessments “right down to individual cut blocks,” Hammond said, and the National Forest Management Act, which sets out clear standards for timber harvesting, as essential tools for the American public to keep industry accountable.
“I don’t think for a minute that forestry is perfect in the U.S.; trust me. But this provides a framework for accountability and communication,” he said.“We need to change the tenure system. What’s the rational for that? That public land was given to corporations because it was viewed by the government of the day to provide social benefits, and it was given and done quickly,” Hammond stressed. “We need to now quickly take back that public forest based on ecological and social needs.
“We better deploy our parachute or we’re not going to like how we land. As people, we need to reassume responsibility for the forest around us in socially and culturally responsible ways, based on ecosystem protection.”