MN Caterpillar Infestation 06 Jun 12

What seems like millions of forest tent caterpillars are being found throughout Minnesota in recent weeks, but experts say this year’s defoliation is not yet “the big one.” Department of Natural Resources officials say it’s leading up to a bigger outbreak in a few years. The DNR is seeing an uptick in the forest tent caterpillar population across the state, especially in Minnesota’s northern counties this year. In west-central counties, the insects have been in outbreak mode for several years, and they are turning up throughout southern Minnesota as well, including in New Ulm. The DNR’s Jana Albers says the caterpillars are native to Minnesota, and usually begin defoliating trees in early spring through mid-June. The caterpillars develop in cycles over the course of decades or more. They set a record in 2002 and 2003 when they stripped 7.5-million acres of trees of their leaves in Minnesota. Fortunately, affected trees almost always recover. The DNR will begin aerial surveys of the state next week to track the caterpillars and other pests.