LDD Moth

The Municipality of Trent Lakes does not have a LDD moth spraying program. Here are some helpful tips and information on how you can manage LDD moths on your property. Further resources are available from the Province of Ontario.

The earlier and more often the pest's life cycle can be interrupted, the more successful we will be in managing the pest.

Overview

The LDD moth (Lymantria dispar), formerly referred to as the gypsy moth, is an insect native to Europe that has been introduced to North America. This defoliator feeds on a variety of hardwood species, preferring oak, birch, and aspen. During severe outbreaks, softwoods such as eastern white pine, balsam fir, and Colorado blue spruce may be affected.

LDD moth outbreaks have become cyclical, typically occurring every seven to 10 years, with outbreaks lasting three to five years. Natural control factors such as disease, parasites and predators eventually combine to cause a collapse of these outbreaks. Healthy trees can withstand repeated years of defoliation before branch and twig dieback start to occur.

Healthy trees can grow their leaves back in the same season, but an ongoing LDD moth infestation may weaken trees and can make them more likely to be damaged from other insects.

Mature larvae are 50 mm long, dark coloured, hairy, with a double row of five pairs blue spots, followed by a double row of six pairs red spots, down the back.

What can you do to stop the spread on your property?

Read the LDD moth fact sheet to learn more about the LDD moth and their life cycles.

There are retailers that sell LDD moth traps and other accessories to help manage the LDD moth on your property. Learn more about these products.

You can take action to remove LDD moth egg masses in winter, prior to eggs hatching in spring. Removing and destroying egg masses in winter reduces the number of hatched caterpillars in spring. Likewise, trapping and destroying both female and male moths in summer reduces the number of moths who then breed and start the egg laying cycle again.

Help mange LDD moths by following these integrated pest management strategy techniques:

May to July: Hand Pick Caterpillars

Handpicking caterpillars is most effective on small newly planted trees, shrubs and plants infested with gypsy moth. If possible, gently shake the tree so caterpillars fall from the leaves. Thoroughly inspect the remaining foliage, branches, and trunk for caterpillars and using gloves, pick them off your tree. Fallen and collected caterpillars should be placed and left to soak in soapy water to destroy them.

June to August (Larger Caterpillar Stage): Burlap Banding

Once caterpillars grow to about an inch (2.5 cm) in length by mid-June, they will move down the trunk to seek shelter from predators and heat during the day. Reduce the number of larvae on the trees in your yard by trapping them.

burlap on trees to manage the gypsy moth

Use the burlap technique to help trap the caterpillars

Required Supplies:

Burlap cloth
Twine or rope
Bucket of soapy water. Dish soap works well

Step-by-Step Instructions

Wrap and secure a piece of burlap cloth around the stem/ trunk of your tree.
Tie twine or rope around the center or slightly below the center of the burlap.
Drape the burlap cloth over the twine or rope so there is an overhang where the caterpillars can crawl underneath to seek shelter during the day.
Check the trap by lifting the overhanging cloth every afternoon and collect any hiding caterpillars.
Put them into a bucket of soapy water for a few days to destroy them.

July to August (Female Moth Stage): Burlap Wrapping

To trap female moths, wrap burlap lower on the trunk of the tree to trap the female moth (which are unable to fly) before it crawls up the tree and lays eggs. This is the dame method used for the larger caterpillar stage. Once captured, drown the moths in soapy water.

August to May: Egg Mass Removal

Survey your property for egg masses and scrape them off surfaces into soapy water to destroy them.

Required Supplies

A flat object such as a butter knife or plastic paint scraper
Catchment container or bag to collect the egg masses
Bucket of soapy water. Dish soap works well.

Step-by-Step Instructions

Place your catchment container below the egg mass
Use your scraper tool to remove the egg mass from the surface. Ensure that all eggs are scraped. Try not to leave any residual eggs in bark ridges or crevices.
Empty the contents of your catchment container of bag into a bucket of soapy water.
Leave eggs sitting in the bucket for a day or two, then dispose of the contents.

It is not possible to eliminate this pest completely if it has become well established in the area. The overall objective is to reduce numbers.

Egg masses can be located high up in trees. Care needs to be taken if trying to access anything aloft, especially if using ladders. Some private tree care companies can be hired to provide this service at heights.

Consult with a Professional

Consult an arborist for treatment options, find a reputable insect control service provider or contact your local garden supply store for the availability of materials.

Contact the Ontario Centre for Forest Defoliator Control (OCFDC) who are a team of experts, originating from Zimmer Air Services. OCFDC is a private company resource that deals with LDD outbreaks, as well as other forest defoliators and deliver effect control programs including aerial spraying.

Videos and Resources

Watch how to identify and remove LDD moth egg masses

Watch the LDD moth egg mass removal

Watch how to set a burlap trap for LDD moth caterpillars