Overview
"The Entomological Society of America today announced a new common name for the Lymantria dispar moth. The invasive moth most familiar in its voracious, leaf-eating caterpillar stage will now be known as "spongy moth."
The Spongy Moth (formerly the Gypsy Moth) was accidentally introduced into Massachusetts in 1869 by a French scientist trying to find a disease-resistant caterpillar to increase the output of silk. Since first being detected in Pennsylvania in Luzerne and Lackawanna counties in 1932, the spongy moth has wreaked havoc on Pennsylvania’s forests, killing millions of oak trees along the way. The spongy moth is now one of the most destructive insects in the eastern United States. It is one of many foliage-eating pests that cause an estimated $868 million in annual damages in the United States.
Spongy Moth Suppression Program - FAQ
Refer to The Pennsylvania Department of Conservation & Natural Resources for more information.
Spongy moth spray operations are typically conducted from late April through the end of May. Spraying of individual blocks is dependent on leaf development and caterpillar hatch and growth.
Spray operations are performed by low flying aircraft, either helicopter or airplane. Operations typically are carried out in the early morning, from first light until noon. On some occasions spraying may be done in the evening if weather conditions allow. All spray operations on State Game Lands will be done with airplanes, there are no helicopters being used on Game Lands. Adjacent lands owned by DCNR or private lands may be sprayed using helicopters.
Game Lands are being treated with Mimic 2LV. The active ingredient is tebufenozide, an Insect Growth Regulator. It selectively controls the insect pest with minimal or no impact upon their natural enemies or upon the environment. (See attached Mimic Fact Sheet).
Mimic is generally considered safe to humans. Most negative side effects happen with repeated, long term exposure to the concentrated product. As with any chemical, it may cause eye or skin irritation if exposed. It is recommended to wash any affected area if irritation occurs.
Mimic is designed to only target lepidopteran species, i.e., moths and butterflies. It does not affect any other orders of insects such as grasshoppers or honey bees. Spongy moths and other defoliating insects generally occur at different times and locations than many of the other native lepidoptera. For example, Spongy moth treatments are conducted in dense forestlands, while species such as the monarch butterfly are associated with grasslands, pastures, parkland, and roadside areas.
Spongy moth is a destructive, invasive insect and not part of Pennsylvania's natural ecosystem. Historically spongy moth impacts have been devastating to the oak dominated forests in Pennsylvania. Massive amounts of oak mortality have led to rapid stand conversions to less desirable forest types across tens of thousands of acres at a time. This can lead to a much lower quality habitat for species ranging from native insects to large mammals, such as deer. Protecting oak habitats with a spray program can also allow for more regular acorn crops now and into the future.
The Department of Conservation and Natural Resources (DCNR) Central Office - paforester@pa.gov - 717-787-2703
Spongy Moth Spraying
Learn about the conservation efforts used by the Pennsylvania Game Commission to preserve habitat against an invasive species formerly called the "Gypsy Moth".