LDD Moth (Lymantria dispar dispar)Image of tree

The LDD Moth, which is commonly referred to as the European Gypsy Moth, is a non-native insect that was introduced to Canada in 1969.

The impacts of defoliation from the LDD Moth can vary from minor to severe and it is generally understood that a healthy tree can withstand some defoliation. However, the defoliation of the trees can make them more vulnerable to disease, other insects, and environmental stressors. A single moth caterpillar can eat an average of one square meter of leaves.

The tree types most commonly impacted by the LDD Moth include oak, birch, poplar, willow, and maple trees. The Moth may also defoliate softwood trees such as white pine and blue spruce.

Not sure what type of trees you have? Check out Forests Ontario to find out.

Frequently Asked Questions (FAQs)
What does the LDD Moth look like?

There are different life stages of the LDD Moth and in each stage the appearance changes significantly.Image of MothUnique characteristics assist with identification:

  • Egg masses – tan coloured, about 4 cm long, and can be found on tree trunks, furniture, buildings etc.
  • Young caterpillars - are black or brown and about 0.6 cm (0.24 inches) in length.
  • Older caterpillars - develop bumps along their backs with coarse black hairs and in the later stage, the caterpillar is charcoal grey with a double row of five blue and six red dots on its back. Mature caterpillars can be as long as 6.35 cm (2.5 inches).
  • Adult moth (male) - the male LDD Moths are greyish brown in colour and can fly.
  • Adult moth (female) - are larger than the males and are whitish in colour with dark markings and/or darker zigzag marks. The female cannot fly and dies shortly after laying eggs.

More images and further information can be found on the Invasive Species Centre website.
What is the life cycle of the LDD Moth?

The LDD Moth has four stages of life:

  • Egg masses - August to mid April
  • Caterpillars - April to June
  • Pupae - June to July
  • Adult Moth - July to August
Management on private property - What can you do?

The Province of Ontario has released a diagram that identifies the LDD Moth’s lifecycle and options for controls during each stage.

Life Cycle of LDD Moth

Looking for professional advice? Contact a tree specialist or an accredited arborist to develop a plan that suits your needs. 

Find an arborist

A common and effective pesticide used to manage an LDD Moth infestation is btk (bacillus thuringiensis kurstaki). Before considering the use of this product, consult a reputable contractor. Pesticides are most effective at the caterpillar stage (Mid-April to Mid-May).

Please use caution. The LDD Moth has long hairs that can cause skin irritation or allergic reactions for some people. For safety, use gloves while handling caterpillars.
How can I safely remove egg masses?
Egg masses should be removed and destroyed at the beginning of each year, before the spring. Below are step-by-step instructions on how to manually remove egg masses:
  1. Place your catchment container below the egg mass.
  2. 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.
  3. Empty the contents of your catchment container or bag into a bucket of soapy water.
  4. Leave the eggs sitting in the bucket for a couple of days, then dispose of the contents.
How do I use a burlap banding kit?

Burlap banding kits are effective at the caterpillar stage of the Moth's life. Below are step-by-step instructions on how to install a burlap banding kit:

  1. Wrap and secure a piece of burlap cloth around the stem/trunk of your tree.
  2. Tie twine or rope around the center or slightly below the center of the burlap.
  3. 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.
  4. Check the trap by lifting the overhanging burlap cloth every afternoon and collect any hiding caterpillars.
  5. Put them into a bucket of soapy water for a couple of days to destroy them.

The use of protective gloves is recommended.

How-to video - burlap against LDD Moth. 

Does the LDD Moth have any natural enemies?

Although direct efforts by humans can assist in managing an LDD Moth infestation, there are also natural checks and balances that exist that control the Moth population:

  • A fungus called entomophaga maimaiga
  • A naturally occurring pathogen called nuclear polyhedrosis virus
  • Predators and insects, such as the ooencyrtus kuvanae wasp; and
  • Extended days of extreme cold (-20 to -25 degrees Celsius)
Additional Educational Resources