New trees new climate

Ash and beech trees are vanishing from Muskoka. The emerald ash borer is slowly making its way north into our region, wiping out ash trees as it goes. Beech bark disease has already begun claiming huge numbers of beech trees.

Neither of these foes are a direct result of climate change, but the warmer summers and milder winters are helping them to spread.

But nature hates a vacuum. And as these lovely trees vanish from our landscape, new opportunities spring up for other species.

In the forest, some of our existing hardwoods will move quickly (for trees, that is!) Maples are what’s known as a “tolerant hardwood,” which means their young saplings can survive very well in low light conditions on the forest floor. As soon as there’s an opening in the canopy above – as happens when a mature tree dies – hundreds of tiny seedlings burst into action, racing each other into the sunlight.

Oak trees have a slightly different strategy, but they too will move into the spaces left by the ash and beech. Red oaks are a particularly good replacement for beech trees: beech nuts are an important food source for everything from bears to squirrels to wild turkeys. Acorns are almost as good.

Basswood is another tolerant hardwood that grows alongside ash and silver maple. It’s sometimes called Bee Tree because its flowers are an excellent nectar source for bees in July, an important asset in these days when bees are under threat. The flowers also smell lovely – the young basswood trees growing near the Segwun dock in Gravenhurst give the area a delightful scent when the flowers are in bloom.

There are also new opportunities in the garden. Muskoka is in a transition zone between the hardwood forests surrounding the Great Lakes and the great boreal forest of the north.  A few more weeks of frost-free weather can make the difference between life and death for some species.

We already see some trees that have a small toehold in Muskoka. Black walnuts, for example, are a dominant tree in many southern Ontario towns. There are a handful in Muskoka, but they only thrive in isolated pockets where the microclimate is a bit warmer. There are some magnificent black walnuts beside Bethune House in Gravenhurst, and some smaller ones around Clevelands House. Planting black walnuts is a long-term enterprise, but it seems likely that it’s a move that could pay off.

Our range of fruit trees is also likely to grow. We likely won’t see peaches in Muskoka in our lifetime, and oranges are definitely out. But plums – which have tended to struggle in the past – might be worth a try.

This is also a good opportunity to bring back something we’ve lost. Elm trees dominated North American landscape plantings for more than a century, but disease wiped out millions of them in the mid-20th century. Ironically, ash trees were a common replacement when the elms died off.

But arborists have been working hard to develop disease-resistant strains of elm, and it seems they’re having some success. There are quite a few varieties on the market now. They grow quickly, and they have a gorgeous vase shape when they’re mature.

Ash and beech might be going, but perhaps it’s now time to revisit the elm. Call us and let’s discuss some options.




Posted in Around Muskoka.