Trailwide – Spongy Moth Spraying
Hiking Safety
Update
05/12/2025
Land managers along the Appalachian Trail (A.T.) have started aerial suppression treatments for nonnative invasive spongy moth caterpillars (formerly known as “gypsy moth”). Aerial suppression treatments are conducted via helicopter, which spray Bacillus thuringiensis var. Kurstaki, or Btk, over large areas. Btk is a naturally occurring bacteria and is widespread in ecosystems. It is not harmful to humans, pets, plants, or most beneficial insects. The spray can be removed with soap and water.
There was an aerial spray last week along the A.T. in New York and the U.S. Forest Service reports that aerial spraying is scheduled in Virginia through this week. Spraying is weather dependent.
To learn more about the impacts of spongy moth on forests, visit the USDA’s website.
Spongy moth caterpillar. Photo courtesy of the VA Dept. of Forestry