While folks up Muskoka way may not agree with me right now, climate change is still a thing: shorter and warmer winters have become the norm, albeit with dramatic weather events scattered throughout the season, such as a dump of over a metre of snow overnight. Acceptance and adaptation are the key working words to dealing with climate change.
As mentioned in a previous article, I am enrolled in a very interesting online course offered by the Ontario Woodlot Association and the Climate Risk Institute. This course is focusing on how this accelerated rate of climate change will impact our forests, and conversely, how our forests play a role in dealing with climate change.
What I like about this course is that the content is local, at least to a provincial level. While no doubt India, Europe, and Australia also have great concerns about their parts of the planet, I prefer to learn in bite-sized pieces, so learning about the challenges just within Ontario and its eco-zones are fine by me.
To help focus on what might happen and where, in regards to a change in climatic conditions, the province has been divided into six zones, each with a list of that particular area’s resilience to change. These zones are very similar to the soils map of the province, which makes sense as it will be soil consistency and depth that determines moisture retention.
In areas of shallow soil, the rating for resilience is low, while deeper deposits, such as we have in Simcoe County, gives a moderate rating. And distance from the equator also is factored in: deep south areas of Ontario will see greater change due to southern species (currently United States) quickly moving their ranges northwards.
The lowlands of Hudson and James Bay will also see significant change as their already fragile ecosystems will have to cope with a consistent rise on annual temperatures.
The good news, if it can be called that, is that where we live (central Ontario) the impacts will be minimal, at least for the next 50 years or so. This is due to the Great Lakes being on our borders to the west and south (it takes a long time to heat up deep water bodies) and the already mentioned soil types.
However, our geographic place of security does not exempt us from the bigger picture. Our local forests will, and already have, suffer from climatic shifts.
Big white spruce trees are already dying due to insufficient moisture in the soil, and invasive insects (in particular emerald ash borers) are surviving what used to be limiting cold winters.
Buckthorn shrubs are thriving and displacing willow, alder and other native plant species, which cascades down to the decreasing number of insects that depended on these now suppressed native species, and then onto the birds that eat the insects.
As the insects disappear plants may not get pollinated, so fewer seeds are created which is also less food for the birds which usually spread those seeds through their poop.
Meanwhile, buckthorns, honeysuckles, dog-strangling vine and others regale in this warm and dry weather, and continue to change their local habitat into a monoculture.
Of course the big question asked by landowners is .... what should I do to keep my forest or landscaped yard healthy? What should I plant that will survive around here once this shift in weather truly settles in?
One of the options presented in this course is to engage in assisted migration. Plants (including trees and all the wildlife associated with each tree species) have always travelled towards the habitat that can sustain them, usually northwards as the glacier melted and left new ground to repopulate.
As an aside, I have trouble with the word ‘migration’ as to me that implies a two-way travel (such as waterfowl do twice a year). While ‘emigration’ is to leave, and ‘immigration’ is to arrive, neither truly captures ‘range extension’ of an already existing species. (See how easy it is to get side-tracked while on this topic of climate change?)
In forestry parlance, assisted migration is to deliberately move a species’ boundary northwards. By example, tulip trees, shagbark hickory, buckeyes and other species are currently found naturally in the Windsor/Sarnia area; try planting them in the Orillia/Coldwater area. If these species are destined (OK, predicted) to eventually get here anyways, let’s speed or assist in that migration.
However, researchers have found that there is already great genetic variation across the province within existing trees, such as red oak. Acorns were gathered from oak forests all across southern Ontario and germinated under consistent conditions.
Acorns from the south produced seedling growth of over 30 cm in the first year, while acorns from the north and east produced seedlings of only 10 cm growth from the same growing medium.
A new recommendation is to enhance existing red oak forests in central and eastern Ontario by ‘migrating’ seedlings brought in from southern Ontario. That way, when the growing conditions around here have changed, the now mature southern oaks will have matured and can continue to thrive in the warmer climate.
I will provide more information in future columns in regards to ways we might adapt to sustain a healthy forest in this part of Ontario.