Family Park to Be Sprayed for Gypsy Moth Caterpillars
Urgent Notice for Olney Mill Residents: Sometime from April 28 to May 10, Montgomery County will be spraying insecticide to control gypsy moth caterpillars. The gypsy moth is the most serious pest of hardwood trees in Montgomery County and state wide. The caterpillars feed on the leaves, often causing defoliation that damages trees and sometimes causes trees to die. Only areas with high numbers of gypsy moths are being treated. The date of the application will depend on weather conditions. M-NCPPC plans to have staff in the Family Park to keep residents off the trails and out of the park during the spraying.
The insecticide B.t. will be applied by a helicopter flying approximately 50 feet above tree top level. Applications will begin at dawn and continue as long as weather conditions are favorable for spraying. Application to a specific area is usually completed in 15-30 minutes. The spray dries on leaves in approximately 30 minutes. The spray contains the bacterium Bacillus thuringiensis (B.t.). To be effective, B.t. must be eaten as the caterpillar feeds on leaves. There is no evidence that the use of B.t. poses any risk to humans, domestic animals, or the environment. A good source of information about the insecticide is available on the internet at
Please avoid touching the wet leaves
Be aware of & avoid the helicopters
For more information about the Gypsy Moth Suppression Program, please see the website:
Montgomery County Department of Environmental Protection, Gypsy Moth Suppression Program: Daytime phone (240) 777-7700; 24-hour hotline (240) 777-7788.
E-mail: AskDEP@montgomerycountymd.gov
