Gypsy Moth Program
The City of Grand Rapids, in conjunction with Kent County Conservation District, will conduct aerial spraying anytime between April and May. Exact application dates will be determined by weather and caterpillar development as the Spring progresses. The intent of this program is to:
- reduce the caterpillar population to tolerable levels in residential and recreational areas
- to preserve 60% or more of the trees foliage, and
- to encourage biological treatment as an alternative to chemical treatment.
Eradication is not possible due to the wide spread of Gypsy Moth and should not be expected.
Proposed spray dates cannot be determined at this time until hatch and foliage development begins. Local television, radio and newspapers will be notified two weeks prior to the proposed spray dates. The spray is applied by air 50 feet above tree level in a very fine mist and application usually cannot be observed from the ground. Spray is still effective if rain occurs later on in the day of application. Spraying will begin at first light (5:45 a.m.) and continue as long as humidity and winds permit.
The pesticide Foray 48F, a water-based formulation containing the active ingredient Bacillus thuringiensis variety kurstaki (Bt) will be used on the treatment blocks. Bt is a naturally occurring soil bacterium that is raised in a laboratory, then concentrated and sprayed on the foliage where feeding caterpillars will digest. Bt is not a contact insecticide; the caterpillars must eat it in order to have any effect. Application rate will be 1/2 gallon per acre (24 BIU). There are no re-entry restrictions on property use after spraying. Bt is harmless to bees, mammals, birds, fish, humans, or insect other than actively feeding caterpillars. Maps showing areas to be treated are identified and the Environmental Impact Statement and Environmental Assessment covering this project are available for your review at the Kent County Conservation District office located at 1328 Bradford NE, Grand Rapids, MI 49503. If you have any questions, please call Kelly Barker, Administrative Assistant at 616-336-8868, Monday through Thrusday, 8:00 a.m. - 6:00 p.m.