gypsy moth caterpillar     gypsy moth   

  • The Gypsy Moth (Lymantria dispar dispar) is native to Europe and is a defoliating insect found in Ontario.  The first detection of gypsy moth in Ontario was in 1969 and had spread noticeably across the Province by 1981. 
  • This insect is considered to the "invasive" due to the fact that it has moved outside of its native habitat and threatens local ecosystems. 
  • Although it is believed the gypsy moth prefers oak trees, the moth actually feeds on a wide variety of trees, including oak, birch, aspen, and various hardwood and softwood trees.

Life-cycle of a Gypsy Moth

  1. Over the winter, the egg stage is often found on the bark of trees, outdoor furniture, or the sides of buildings.   The egg masses are covered with tan coloured hairs and are about the size of a loonie and may contain anywhere from 100-1,000 eggs.
  2. Eggs hatch in the spring and the larvae ascend the trees to feed on new foliage, generally during the day. 
  3. As the caterpillars mature the feeding then occurs mainly at night. The mature caterpillars are roughly 50mm long, dark hairy colouring, with a double row of 5 pairs blue spots, followed by a double row of 6 pairs of red spots down their back. 
  4.  Feeding is completed around July.
  5. Male gypsy moths are light brown and slender bodies and female gypsy moths are white and heavy bodied. 

Report Gypsy Moth Issues

defoliation map 2019

It is believed gypsy moth outbreaks occur every 7-10 years.  The Township's annual spray program occurred in late spring 2020, but due to the COVID-19 pandemic, the informational Public Meetings were unable to occur.  There was also a widespread shortage in the insecticide spray that is used by the company for the aerial spray program. 

West Lincoln, specifically in the area of Caistor Centre and Caistorville, has been significantly impacted by the infestation of gypsy moths in 2020.  

If you wish to be contacted early next year to receive information for the 2021 Gypsy Moth Spray Program please e-mail planning@westlincoln.ca or call 905-957-3346 ext. 5134. 

Alternatively, if you wish to report a citing or issue of gypsy moth infestation directly to Early Detection & Distribution Mapping System, who partners with Ontario Federation of Anglers and Hunters, Invasive Species Centre, Ontario's Invading Species Awareness Program, and the Province of Ontario, please visit their website, www.eddmaps.org/ontario/.

The above pictured map is generated each year through the Forest Health Monitoring Program.  The information is collected through aerial surveys across the province and data is collected to produce forest disturbance maps.  The final map is generally available later in the year once data has been collected and ground verified.   

Helpful Websites

Please visit any of the following websites for useful information and tips when dealing with a gypsy moth infestation. 

Province of Ontario

Government of Canada

Ontario's Invading Species Awareness Program  

Town of Erin (useful tips for protecting your trees)