gypsy moth caterpillar     gypsy moth   

  • The Spongy Moth (Lymantria dispar dispar) is native to Europe and is a defoliating insect found in Ontario.  The first detection of spongy 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 Spongy 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 Spongy 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 spongy moths are light brown and slender bodies and female spongy moths are white and heavy bodied. 

Report Spongy Moth Issues

It is believed spongy moth outbreaks occur every 7-10 years.  The Township's annual spray program occurred in late spring 2020 and 2021, but due to the COVID-19 pandemic, the informational Public Meetings were again unable to occur in 2022.  There was also a widespread shortage in the insecticide spray that is used by the company for the aerial spray program for the past several years. 

West Lincoln, specifically in the area of Caistor Centre and Caistorville, has been significantly impacted by the infestation of spongy moth  in 2020 and 2021.  

If you wish to be contacted to receive information for the spongy moth Spray Program please e-mail planning@westlincoln.ca or call 905-957-3346 ext. 5134.  For additional information regarding the spongy moth Spray Program, please see below.   

Alternatively, if you wish to report a citing or issue of spongy 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/.

2022 Spongy Month and Spongy Moth Spray Program Information 

Due to an extremely limited amount of Bt (Foray 48B) spray, the 2022 Spongy Moth Spray Program (registration period) has been closed earlier than anticipated.  

Forms and Information 

2022 Spongy Moth Spray Agreement with Cost Formulas

Spongy Moth Aerial Spray Program Backgrounder

MDMS - Spongy Moth Spray (Foray 48B) 

Helpful Websites

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

Province of Ontario

Government of Canada

Ontario's Invading Species Awareness Program  

Town of Erin (useful tips for protecting your trees)