Jorge Maria
Pontiac June 16, 2021
Gypsy moths are causing havoc in Eastern Ontario make an appearance on the Quebec side of the Ottawa River.
Gypsy moths are not new to the Outaouais. Scientists studied them as far back as the 1930s in Quebec. With increasing infestations in Ontario’s Lanark and Renfrew counties, the Ottawa river does not. . .
provide much of a barrier for the flying insects.
The caterpillars appear from April to June, when they are most dangerous to deciduous and coniferous trees, devouring leaves in this crucial part of their development. What this means for forests, orchardists and maple bushes are tree leaves pockmarked with holes hindering growth. In severe cases, gypsy moths can scour a tree’s leaves completely.
At Coronation Hall, Gary Graham walked THE EQUITY through some of the damage in the cidery’s apple orchard. Gypsy moths left one full-grown tree decimated. Scraps of leaves clung to stems, killing the tree’s chance of bearing fruit this year. This level of destruction is highly unusual, according to Graham.
Graham estimated there are three trees in the 12-acre orchard severely damaged like this one. Of greater concern is the newly planted trees too young to bear fruit. The trees are much more delicate and a small infestation can hinder growth setting back fruit production or even kill them.
The orchard’s grass is yellow and dying. Graham believes the warm, dry spring has exacerbated the problem. “A good, heavy rain or a lot of rainstorms will help because it washes the eggs off,” Graham said. Without regular rain, the orchard is forced to resort to using pesticides to eradicate the insects.
When The Equity spoke to farmer and sugar bush owner Simon Alary about gypsy moths, the semi-drought conditions were also on his mind. “I’m more concerned about the lack of rain,” Alary said.
Even still, the pests have made their way to his property. On a single tree not far from his home, more than 20 caterpillars crawled about on a half-foot section of the tree.
For mature trees, like the ones in Alary’s sugar bush, the damage can hinder the growth of trees but isn’t likely to put a damper on maple production. However, continuous infestations over time can eventually kill a tree.
According to Ontario’s Ministry of Natural Resources and Forestry, gypsy moth infestations typically happen every seven to 10 years, but climate change leaves the future of these outbreaks uncertain.
Maple leaves are a favourite snack, but so are deciduous trees in Quebec forests such as poplar, willow and other broadleafs. Severe infestations like the one in Eastern Ontario last year can leave forests stripped bare.
In an Ontario study, the moth population saw an increase of 1,200 per cent in 2020. Ontario researchers expect this year to be worse.
The Equity reached out to MAPAQ for comment but did not receive a response before our publication deadline.
