The Lymantria dispar dispar moth (LDD moth) is an invasive pest that eats the leaves of trees. The LDD moth is also called the spongy moth.

On this page:

  1. About the LDD moth
  2. Life cycle and control options
  3. Our response
  4. External resources

About the LDD moth

The LDD moth is an invasive pest native to Europe. It was first found in Ontario in 1969 and has since spread across southern Ontario.

The LDD moth is a forest pest concern because the caterpillar, or larva stage of the insect, eats the leaves of trees. If the larvae population is too high, they can eat the leaves of whole trees and forests. When combined with a dry hot summer or other pests, this can lead to the death of many trees.

Life cycle and control options

If you see LDD moths on your property, you can manage them yourself. Please do not try to remove LDD moths from trees on city property, like in parks or on your street.

The timing of each stage depends on climate and location. Open the accordions below to learn about each life stage and tips for controlling the moths.

August to mid-April: egg masses
Check your property for egg masses (you’ll find them mostly on the bark of trees) and scrape them off and into soapy water to destroy them.
Mid-April to mid-May: early-stage caterpillar

Use biological pesticides.
Mid-May to June: late-stage caterpillar
  • Wrap burlap around the stem/trunk of your tree and use a string or rope to create a trap. Then, fold the top half over the bottom half to form a bit of a ring. You should only use burlap and no other sticky tape or substances as this could harm other insects or animals.
  • Caterpillars may start to hide under the burlap bands. Check the trap by lifting the burlap and collecting the hidden caterpillars.
  • Remove the caterpillars and put them in a bucket of soapy water for a day or two.

What to look for

The caterpillars of the LDD moth are dark and hairy. They have five blue dot pairs and six red dot pairs on their back.

Photo of a gypsy moth on a leaf
July and August: adult moth
Female moths cannot fly. To trap female moths, wrap burlap lower on the trunk of the tree to trap the female moth before it crawls up the tree and lays eggs. Collect the moths and put them in soapy water for a day or two. 

Detailed control tips are available from Natural Resources Canada.

Video

Watch this video from Reep Green Solutions to learn how to protect your trees from spongy moths.

Our response

We do not have a LDD moth control or management program in place. We’re working with other local municipalities and the Grand River Conservation Authority to monitor the local populations. LDD moths are present in many areas of Kitchener and their populations are currently high.

We expect to see some damage to trees and expect that the level of damage is something that trees will recover from.

External resources