The European Gypsy Moth is a non-native defoliating insect that was introduced to North America in 1869 and first discovered in Burlington in 1981. The caterpillar or larva stage of the Gypsy Moth eats the leaves of trees causing the trees to be more vulnerable to disease and attack from other insects.
The city’s Roads and Parks Maintenance department working alongside residents and volunteers have traditionally kept the Gypsy Moth population under control using a number of integrated pest management (IPM) control methods that include scraping egg masses from trees; installing burlap skirts and placing sticky bands around trees; using pheromones to confuse male moths; and leaving wooded habitat around trees, shrubs and garden plants to encourage the presence of the moth’s predators.
In 2006 and 2007 the City of Burlington faced significant Gypsy Moth outbreaks. The egg mass scrapings and other control measures in 2007 had some effect on the Gypsy Moth population; however, the harsh summer drought and mild winter in 2007 prevented a significant decline in the population. The results of an egg mass survey conducted in October 2007 clearly indicated that populations have increased substantially since 2006 in most areas. The Gypsy Moth infestation levels in Burlington and many other areas of Southern Ontario have reached such high levels that they can no longer be effectively controlled by manual methods alone.
Based on research and recommendations from city staff and an independent forestry management expert, aerial spraying of the pesticide Btk (Bacillus thuringiensis subspecies kurstaki) is seen as the most effective way to deal with the Gypsy Moth in the heavily infested areas.
What You Can Do:
Gypsy Moth Control Methods For Homeowners And Residents
The City of Burlington urges all residents to participate in the control program for Gypsy Moth by scraping and destroying egg masses, catching and destroying caterpillars. Your choice of control method is closely linked to the Gypsy Moth’s stage of development, and is described below by season.
November-late April - Remove and destroy egg masses
Scrape off egg masses with a dull knife and place them in soapy water for a few days before discarding them in the garbage. If they fall on the ground crush them with your shoe.
Egg masses are easy to vacuum off trees, buildings and other objects with a portable or a household vacuum cleaner. You can reach egg masses that are located at higher elevations on the tree by adding a number of extension pipes to the vacuum hose, or with the help of a ladder. Place collected egg masses in soapy water for a few days and then discard them in the garbage.
|Late April-early May - Place sticky barriers, or bands on the tree trunk.|
Wrap duct tape around the tree trunk and apply a thin coat of sticky material (ready-to-use products are commercially available in most garden centres) to the duct tape. This prevents young caterpillars from crawling up the tree. This control method will effectively trap only young caterpillars that are already crawling on trees or that emerge from egg masses that are situated low on a tree trunk or on other buildings and objects.
|Late May-August - Replace sticky bands with burlap (cloth) bands.|
Trap and destroy caterpillars by placing burlap (cloth) bands on trees. Wrap burlap that is approximately one metre wide around the tree trunk, tie it at the middle with a rope and fold it. Caterpillars feed at night and hide during the day in shelters that protect them from the heat. They will congregate under the burlap. Destroy caterpillars that emerge from under the burlap late in the afternoon before they crawl back to the canopy to feed.
- Health Canada - Effective control of Gypsy Moths
- Health Canada – Pest Management Regulatory Agency (general information)
- Health Canada – Pest Management Regulatory Agency (European Gypsy Moth)
- Natural Resources Canada (Gypsy Moth Forest Pest Leaflets)
- Natural Resources Canada (additional information)
Links to Other Gypsy Moth Control Webpages:
- City of Mississauga : http://www.mississauga.ca/
- City of Toronto: http://www.toronto.ca
- Government of Nova Scotia : http://www.gov.ns.ca/
- United States Department of Agriculture Factsheet: http://www.fs.fed.us/
- US Forest Service: http://www.fs.fed.us
Trees in the urban forest are often put under stress. When trees have been put under stress by compacted soils, drought, insect infestations, air pollution and hot temperatures, it is important for homeowners to take an active role in maintaining the health of their trees. By following these general tree management tips homeowners can greatly improve the health and recovery of stressed and damaged trees on their property.
Homeowners should make sure to regularly water trees during dry spells and when the tree is suffering stress from insect defoliation (loss of leaves). Regular deep soaking during the early morning hours is recommended. Water absorbing roots are located in the upper 25 cm of the soil and extend beyond the canopy.
Mulching is an excellent way to keep the soil moist for longer periods of time and encourage healthier roots. Place organic mulch, such as wood chips, around the base of the tree.
- Avoiding unnecessary damage
Avoid unnecessary excavations, grade changes, soil compaction, root cutting and placing hard surfaces around trees. These activities can destroy roots and make it more difficult for water to get to the tree. Homeowners should also refrain from using salt and herbicides around trees.