Department of Agriculture officials are still unsure of the source of gypsy moths that have infested parts of Cook and Lake County. But they're concerned the highly destructive pest may be taking hold in Minnesota.
The moths can arrive in cocoons attached to firewood or vehicles from infected parts of the country.
Most of the gypsy moths trapped in Minnesota last year were in Cook County -- on the Grand Portage Indian Reservation. Nearby areas were treated two years ago, said Lucia Hunt, with the Department of Agriculture's Gypsy Moth Unit.
"The areas where we treated in 2006 still looked very clean. There are very few -- very low levels of moths that we found in there," Lucia said. "But it's in the adjacent sections that we have found new moths in our traps in the 2007 survey."
Public meetings are underway in North Shore communities this week to explain the department's plans to treat some 85,000 acres.
If allowed to spread, the moths are capable of stripping leaves from wide tracts of forests. The damage is both unsightly, and stressful for the trees, including birch trees. Trees already weakened by factors like drought can die from a gypsy moth infestation.