Spray Block Maps and Information
Spongy Moth
DNR Aerial Treatments
The Wisconsin Department of Natural Resources (DNR) organizes aerial spray treatments on DNR-managed lands, such as state parks and forests.
View DNR 2024 spray block maps [PDF].
Landowners, land managers and property ownership groups may decide to hire an aerial application business to conduct an aerial spray. The cost is about $80-100 per acre.
For more information, check out the Spongy Moth Resource Center [exit DNR] and view the DNR guide Organizing an Aerial Spray For Forest Pests: Recommendations And Regulations [PDF].
“Slow The Spread” Aerial Treatments
The Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP) uses aerial spraying every spring and summer, mainly in western Wisconsin, to treat low-level populations in non-quarantined counties as part of the national Slow the Spread program [PDF exit DNR].
- May-early June: A bacterial insecticide is aerially applied to kill young spongy moth caterpillars.
- Late June-July: A mating disruptor is aerially applied to prevent adult moths from mating.
![Map: Spongy Moth Quarantined Counties [exit DNR]](https://fyi.extension.wisc.edu/spongymothinwisconsin/files/2023/05/SM-Quarentine-Map-2023-791x1024.jpg){kind=link}