The gypsy moth is considered to be the most destructive forest pest in the country. When they're caterpillars, they have a voracious appetite for almost any kind of tree or bush, and they can strip a tree bare overnight.
Gypsy moth caterpillars are capable of defoliating hundreds of thousands of acres of forest per year. This month, the Washington State Department of Agriculture is installing thousands of gypsy moth traps around the state.