The warmer weather is a welcome sign of summer, but this time of year can also come with hazards for your trees and their health. Gypsy moths (now commonly referred to as spongy moths) can have serious negative effects on trees. They are something to keep an eye on starting in Spring and all through the summer months.
How do Gypsy/Spongy moths negatively affect your trees?
1. Defoliation
Gypsy moth caterpillars feed on tree leaves, often stripping trees bare. Oaks are a favorite, but they also feed on birch, aspen, willow, and even some conifers like spruce and pine.
Heavy defoliation reduces the tree’s ability to photosynthesize, which stresses the tree and makes it vulnerable to disease, drought, and other pests.
2. Tree Stress and Decline
Repeated defoliation (especially over consecutive years) can weaken trees to the point where they die. Stressed trees are more susceptible to opportunistic pests (like bark beetles) and fungal infections.
3. Death of Trees
While deciduous trees can often re-leaf in the same season, conifers (like pines) do not recover well and can die after a single heavy defoliation. Two or more years of defoliation in a row can kill even otherwise healthy hardwoods.
4. Aesthetic Impact
The loss of leaves reduces shade, alters habitat for wildlife, and affects the overall landscape and aesthetics of your property.
Steps you can take to protect your trees from Spongy Moth
1. Manual removal
Look for egg masses and scrape them off (egg masses can be killed by placing in hot water with ammonia or bleach)
2. Burlap barriers
Burlap bands can be used to trap migrating caterpillars.
3. Mulch management
Maintain a clear space around trees to prevent eggs from hatching in debris. We offer free mulch delivery!
4. Prune and remove affected branches
This helps to prevent the spread of infestations. If you need help, we have tools and equipment to reach the high branches. Request Quote.
5. Consult an arborist
Consult an arborist at Hilltop Tree Care for treatment options and tips to keep your trees healthy and happy. Contact us.
Don’t wait for problems to grow—let’s keep your trees healthy, safe, and beautiful this season!
MORE RESOURCES:
Sponge moth – Inspection Canada website
Town of Halton Hills – Invasive Species