The DNR will spray in eastern counties where the gypsy moth is already established while the Department of Agriculture will slow the spread in the southwest.
The Ag Department's Gypsy Moth Program Coordinator Chris Lettau says it's critical to keep the tree killing moth from spreading for the sake of the state's forest economy. Lettau says it can affect the timber industry, nurseries and Christmas Tree farms.
Lettau says a couple of years ago gypsy moths defoliated sixty thousand acres of forest land in Marinette County.
Between now and the end of July, low flying planes will be spreading non-toxic pesticides including pheromone flakes that give off the scent of female moths. The males spend the two weeks they have as adults chasing fake females and never reproducing. That means no eggs and no new moths the following year in that area.
Lettau says, "it's kind of a cruel trick but it works."