MADISON, Wis. (WRN) — A new invasive species is spreading across Wisconsin.
The Department of Natural Resources says eastern Asia’s elm zigzag sawfly was first detected in the U.S. three years ago and was first seen in the state on July 4th in Portage County.
The insect, named for the zigzag pattern its caterpillars chew in elm leaves, has now spread to 17 counties statewide.
The DNR says the pests only cause minor or cosmetic damage to elm trees, but could lead to possible defoliation. Their presence is usually not a cause for alarm, but careful monitoring is recommended.
