There’s no doubt that British Columbia is a forested province and, though there’s still some debate about causes, it’s also generally agreed that our climate is changing. What do the impending changes mean for B.C.’s forests in general and the Semiahmoo Peninsula in particular?
If forecasts are to be believed, weather patterns will be erratic, wetter and hotter. The impact on forests has already been seen in the recent damaging outbreak of mountain pine beetles as one consequence of a change which was brought about, at least in part, by a series of relatively mild winters.
The worst fire season on record was 2018. The tree line can be expected to rise in the mountains and northwards at the extremity of the boreal forest. This will affect timber productivity and allowable harvesting. The increasing risk of forest fires will force municipal authorities to give more thought and attention to the interface between sprawling housing development and the forest edge. A changing climate will alter the make-up of plant species in many habitats to the detriment of creatures there today, some of them such as mountain caribou already endangered.
Local ski resorts will need to adjust to shortened winter sports seasons. Trees which are struggling with adverse conditions will grow only slowly, so that they will give off less oxygen and store less carbon than healthy vigorous ones and will be more susceptible to insect attacks.
These are largely province-wide challenges with little direct or immediate relevance to our communities, though they will have impacts.
Where do we fit in? Landscapers and gardeners must accept that some of our beloved tree species like the western red cedar will not thrive in the expected future conditions. If we must plant Douglas firs, then we should use the interior variety, which is better adapted to hotter, drier weather than its coastal cousin. The native interior Ponderosa pine can be expected to do well in the new climate regime here.
We should not shy away either from looking southwards at some of their species and varieties which are flourishing inland and away from the coast where conditions may be a foretaste of our future. Will there be a role for such Mediterranean species as the robust, long-lived olive?
We should ask ourselves if small trees like mountain ash (rowan if you’re a Scot), and black mulberry will not be as efficient at providing greenery and leafy canopy as struggling firs and oaks. Shrubs, too, can be valuable and there are several native species to consider – hawthorn, hazel, Indian plum, ocean spray, Saskatoon berry, vine maple and willows are just some of them. Recent research indicates that, since they grow at tail-pipe level, shrubs are better than trees at trapping vehicle exhaust fumes and toxins, so perhaps our boulevards should be lined with hedgerows instead of sentinel-like rows of trees with their canopies far above ground-level pollutants.
Surrey has at least two water-wise gardens demonstrating planting make-up suitable for warmer, drier conditions. How far will our nurseries and garden stores go to lead gardeners away from conventional or fashionable stock to more innovative plantings? Could our municipal gardens provide leadership and minimize their watering requirements by planting only drought-tolerant species and varieties?
A lawn needs only about two centimetres once a week to keep it healthy through a dry summer; in other words deep, infrequent watering is the optimal routine and perhaps we should use alternatives to traditional lawns.
Let’s heed King Canute and, instead of trying to halt the naturally inevitable, learn to live with a changing, unpredictable climate.
Dr. Roy Strang writes monthly on the environment for the Peace Arch News.