Invasive Species - Gypsy Moths

Gypsy moth caterpillars are stripping trees in many areas of Ontario and more important to us, South Frontenac. Caterpillar droppings and shredded leaves litter decks, roofs, and trails.

Gypsy moths are an unpleasant cyclical event. At this point, neither the provincial Ministry of Forests nor the Township or the provincial park has any plans to address the outbreak.

There is an abundance of information online about gypsy moths. London, Ontario, has helpful information, including a video, on how individual property owners can help control the infestation, most importantly by destroying egg masses. 

Ontario Today, a daily program on CBC Radio hosted by Rita Celli, also offered a good one-hour interview and call-in with Paul Robertson President of the Ontario Woodlot Association. Click to replay the CBC Podcast from July 16, 2020.

Lasy week, on July 30th, three members of your executive attended a webinar hosted by FOCA (Federation of Ontario Cottagers' Association), for a very informative one-hour session concerning Gypsy Moths, what areas of the province they are affecting, and suggestions on how to control them. Some key points of the session are:

  • an infestation typically lasts 3 years;
  • most hardwoods can endure 3 years;
  • white pines die once they are 100% defoliated;
  • Gypsy Moths are cold tolerant to -20C;
  • eggs below snow are likely to survive;
  • the Gypsy Moth lays ½ its eggs below the snow;
  • Populations increase in hot dry summers, decrease in wet springs (Entomophaga maimaiga).

Homeowner Options:

  • Through a licensed applicator, treat with B.t.k. as it kills 60 to 80%, knocking down the population to reduce impact in the next year;
  • Burlap trap, daily collections;
  • High-pressure water spray to dislodge caterpillars;
  • Trunk tape coated in a sticky paste.
Click to watch the Webinar Presentation for a detailed guide on managing Gypsy Moths (online posting; 1hr 15 min). Alternatively, click to download the FOCA webinar slides (PDF format, 7 MB).

FOCA posts information about Gypsy Moths and other invasive species on their webpage. Visit here for more information.

The South Frontenac website also offers some helpful information about the outbreak of Gypsy Moths in the area. Click to learn more about Gypsy Moth management and other resources. They state that when outbreaks do occur, property owners and municipalities may wish to conduct spray programs or take other actions to keep the trees from being defoliated. 

For further assistance, please contact the Ministry of Natural Resources and Forestry (MNRF) toll-free at 1-800-667-1940 to learn about their invasive species action plan or visit their website through the link above.

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