Spongy Moth invasion: Shenandoah National Park gears up for aerial defense

Shenandoah National Park is preparing to spray for spongy moth caterpillars along sections of Skyline Drive. 

The park announced this week it will use a naturally occurring bacteria to suppress the non-native caterpillars between miles 39 to 51, and the Skyland and Big Meadows areas. 

Spraying is weather-dependent, but it is expected to happen between May 15 - May 20.  3,150 acres will be sprayed by a specialized helicopter between 6:30 a.m. and 12:00 p.m. on two separate mornings.

Over the past two years, park officials say spongy moth numbers have increased, causing forest defoliation in the central section of Shenandoah. Additional defoliation would likely cause a significant number of trees to die, which would create safety hazards and destroy forest habitats. 

The park’s Spongy Moth Suppression Program aims to provide visitor safety along Skyline Drive and other developed areas by reducing hazardous tree development and protecting sensitive historic and natural land. 

The effort at Shenandoah National Park is part of a larger U.S. Department of Agriculture Forest Service strategy to suppress spongy moths in the area on a total of over 16,000 acres, mostly on the Washington and Jefferson National Forests.

Frequent visitors should check the park's website during the spraying window for more information.