LETTRE

Replacing Ash trees with non-native species

 

It was with some joy I read in the August 1 issue of the Aylmer Bulletin that the City of Gatineau will be replacing the 36,000 ash trees wiped out by an invasive species, the emerald ash borer. Finally, we have some good news on the environment front! However, upon further reading, the City has decided, obviously not based on science, to spend $2.36M to plant three species of trees not from Ontario or Quebec.

The International Union for the Conservation of Nature has determined that invasive species are the second most significant threat to biodiversity, after habitat loss. In their new environments, invasive species can become predators, competitors, parasites, and diseases of our native plants and wildlife. We just witnessed that with the borer!

There is no doubt that these three selected species have wonderful ornamental qualities. The ginkgo tree is native to Asia and produces very foul-smelling fruits with seeds that are toxic to humans if not handled correctly. The honey locust tree, from central USA, is a major invasive environmental and economic weed in agricultural regions of Australia. The Homestead elm, a hybrid of Siberian-USA elms, is not very heat tolerant and many plantings have recently been replaced by other trees in countries such as Holland.

While the tree species the City of Gatineau has selected may, in the end, be harmless, I question why we are not planting native species that can provide food and habitat for our pollinators and other wildlife. Aylmer already has some magnificent native trees, such as the black walnut, red oak, and sugar and red maples, lining its streets.  Wouldn’t it be nice if the next generation will be able to enjoy these native trees and the wildlife associated with them? Finally, there is no doubt that the native species will be more economical than the ‘exotic’ species, helping to save our tax dollars to resolve other environmental issues.

Michael Wong
Aylmer