Property owners in Norfolk County have received a timely reminder that 2021 could be a pivotal year for their woodlots.
Adam Biddle, Norfolk’s forest conservation officer, said this year could be a tipping point for woodlots that were stripped of their foliage in 2019 and 2020 by gypsy moth caterpillars.
“If they get defoliated again this year, we’d be looking at significant mortality and significant tree loss,” Biddle said.
Biddle was addressing Norfolk council on Jan. 7 from a remote location during the second day of the county’s 2021 budget deliberations. At issue was $22,700 Norfolk will spend this year to spray 283 acres where gypsy moth egg clusters have reached a critical mass.
Forest-related pests and diseases are top-of-mind in Norfolk because more than 30 per cent of the county is covered in trees. The county is also home to the highest concentration of Carolinian forests and tree-types in Canada. Norfolk has served two terms in recent years as the Forest Capital of Canada.
Port Ryerse Coun. Chris VanPaassen suggested Norfolk has a co-ordinating role to play with the campaign ahead. Norfolk’s forestry division organized the mass spraying of woodlots in 2008 – the last year gypsy moths were at the top of their cycle. Then as now, the former Windham and Charlotteville townships were at the epicentre of the worst infestations.
Biddle said his department has no resources to organize a broad-based campaign this spring. However, the forestry division will serve as an information clearinghouse for property owners who want to learn more about the pest and steps they can take to knock it back. VanPaassen suggested the Norfolk Woodlot Owners Association should be asked to join the effort.
“We can spread the word,” said Bill Cridland, Norfolk’s general manager of community and emergency services. “It has to be public anyway. That’s the next logical step.”
Biddle said there is no cost advantage to bundling properties with an eye to a volume discount. However, co-ordinating with the county ensures that woodlots are sprayed at an optimal time for maximum decimation.
The remedy involves a solution containing a bacterium known as bacillus thuringiensis, which is harmless to plants, animals and people but lethal to gypsy moth caterpillars. Woodlot owners are also encouraged to examine the trunks of their trees for egg clusters and brush any they find to the ground.
The caterpillars don’t kill trees but seriously weaken them. This leaves trees vulnerable to disease and boring insects.
Species most vulnerable include oak, birch, poplar, willow, maple and other hardwoods. Trees stripped of their foliage will re-flush if attacked early in the growing season. However, if the second leaf set is eaten as well, trees fall dormant and save their energy for another growing season.
Meanwhile, they miss out on a year of photosynthesis and the nutrient storage they need to successfully over-winter. Defoliation coupled with a hot, dry summer will kill all but the strongest trees.
Gypsy moth predation is a major concern for the Long Point Region Conservation Authority, owner of more than 10,000 acres of forested land. Delhi Coun. Mike Columbus, chair of the conservation authority, said conservation authority staff are discussing plans to control infestations on their property.