Forest Health_Content Page_Aerial Spray Info

Spray Block Maps and Information

Spongy Moth

Please note: The State of Wisconsin does not offer a state-sponsored or cost-share program to have privately owned land treated for spongy moth populations.

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.

View DATCP 2024 spray block maps [exit DNR].

View DATCP 2024 spray block book maps [PDF exit DNR].