Spongy Moth Information Center
Overview
The spongy moth (Lymantria dispar dispar), formerly known as gypsy moth, is a destructive pest which defoliates and destroys many tree species, especially oak trees.
The spongy moth is an invasive species which originated in Europe and was introduced to the Northeast US in 1869. Spongy moths have been causing significant forest damage in Pennsylvania since the 1970s.
Female spongy moths lay their eggs as light tan egg masses on trees, stones, and flat sheltered areas in the months of June and July. The eggs then hatch the following spring between mid-April to early May.
Spraying to Treat Spongy Moth in Ferguson Township
In 2024, Ferguson Township is partnering with Patton Township to control Spongy Moth. The decision to move forward with spraying was based on the amount of egg masses in areas that present the likelihood of deforestation and potential tree loss from the insect.
The Board of Supervisors approved the 2024 Operating Budget with an allocation of funds for use to treat areas identified as having egg masses with high potential for an elevated population of Spongy Moths.
The Township will use BtK to treat the Spongy Moths. BtK, short for Bacillus thuringiensis var. kustaki, is a bacterium found naturally on leaves and in the soil. These bacteria are tiny little factories that produce protein crystals that kill a specific group of insects. It is the safest and most effective eradication method for spongy moths. Btk only impacts caterpillars and will not harm other beneficial insects. It is not harmful to mammals, birds, or fish.
Spraying will be conducted in late April to mid-May of 2024. The timing of the application targets the Spongy Moth specifically as young caterpillars while minimizing impacts to other moths and butterflies which generally mature later in the summer.
Those residing within one of the proposed areas have been notified of the Township's intent to conduct aerial spraying. Spraying will be free of charge. There is an option to opt out of the spraying program for those who do now wish to participate.
To obtain additional information, please contact the Township Arborist at (814) 238-4651 or email arborist@twp.ferguson.pa.us.
Learn More about Ferguson Township's Spongy Moth Spraying Program
Ferguson Township 2023 Egg Mass Survey Results with Maps
Block Maps of Areas of Proposed 2024 Spray Areas
Letter Sent to Residents in Targeted Spray Areas
Information on BTK Insecticide provided by the US Forest Service
Safety Data Sheet on Foray 48B Insecticide
Label for Foray 48B Insecticide
BTK Fact Sheet
Opt Out Notification Letter
Final Spray Block Maps (Post Opt Out)
Spray Reimbursement Form
Additional Resources
Penn State Extension - Guide to Spongy Moth Egg Mass Surveying
PA Game Commission - Spongy Moth Spraying Information
US Department of Agriculture - National Invasive Species Information Center (Spongy Moth)
PA Department of Conservation and Natural Resources: Lymantria dispar dispar (Spongy Moth)
Centre County Government Spongy Moth Information
College Township Spongy Moth Resource Page
Patton Township Spongy Moth Resource Page
Ferguson Township Summer 2023 Spongy Moth Update