Gypsy Moth Treatment to Take Place in Jackson, Allamakee and Winneshiek Counties June 27 to 30
Posted: 06/21/2011
DES MOINES - The Iowa Department of Agriculture and Land Stewardship and Iowa Department of Natural Resources today reminded Jackson, Allamakee and Winneshiek County residents that pheromone flakes will be released from low flying airplanes next week to help slow the spread of gypsy moths, a pest that can be destructive to trees and shrubs.

The treatments will take place on June 27 and 28 in Jackson County and on June 29 and 30 in Allamakee and Winneshiek counties.

Iowa is part of a nine state effort to slow the spread of gypsy moths across the country using pheromone flakes to disrupt the mating process. In total, 158,649 acres of forestland will be treated in Iowa.

The treatment is being conducted through a partnership between the Iowa Department of Agriculture and Land Stewardship, the Iowa Department of Natural Resources, and the USDA Gypsy Moth Slow the Spread Foundation. Information on the foundation is available at

"We want to make people aware of what is going on because they will likely see the low flying planes as soon as the sun is up on treatment days," said Tivon Feeley, Forest Health Program Leader with the Iowa DNR.

"Planes will be releasing pheromone flakes specifically designed to mask the female gypsy moths natural pheromones to confuse the males and make it more difficult to find the females," Feeley said. The flakes will be released over the tree canopy.

"The pheromone is specific to gypsy moths so it does not affect humans or other animals or plants, including moths and butterflies," said Robin Pruisner, State Entomologist with IDALS. In addition, "pheromone flakes will only be applied to tree canopy, not row crops, pasture lands, or waterways" said Pruisner.

Iowa, along with Wisconsin, Illinois, Minnesota, West Virginia, Indiana, Ohio, Virginia, North Carolina, is on the front edge of the gypsy moth spread across the country. Iowa is not currently listed as a gypsy moth infestation state. The use of pheromone flake treatments will help delay the establishment of gypsy moth in Iowa by several years.

Gypsy moths feed on more than 300 different species of trees and shrubs, with oaks a favored species. Each larva can grow up to two inches long and can consume up to 11 square feet of foliage from early May through June.

When abundant, caterpillars can completely defoliate trees. Although healthy trees can survive defoliation, repeated removal of leaves can kill a tree. Older, less vigorous trees suffering from drought can be killed by a single defoliation.

More information on the Gypsy Moth can be found at