Spongy Moth in Ontario

Ontario has been experiencing an outbreak of spongy moth (previously referred to as gypsy moth and LDD) since 2017, particularly in southern Ontario and parts of the northeast region of the province. The outbreak peaked in 2021 and declined significantly in 2022.

Last year, the Ministry of Natural Resources and Forestry (MNRF) conducted aerial and ground surveys to map damaged areas and forecast defoliation for 2023. The results suggest the outbreak area and severity will continue to decline in 2023. Some areas, mostly in the southwestern part of the province, may still experience severe defoliation, but it’s expected that large contiguous areas of defoliation will be limited.

Below are links to additional resources about spongy moth outbreaks:

• Spongy moth and other defoliators
• Ontario's Invasive Species Centre 
• Forest Health (Spongy Moth) Roles and Responsibilities
• Spongy Moth Information Sheet
• Letter from The Honourable Graydon Smith, Minister of Natural Resources and Forestry Re: Spongy Moth Outbreak