Invasive moths continue to surge in parts of the BWCA and North Shore

The Minnesota Department of Agriculture says an invasive moth continues to pose a threat to the woods near Lake Superior, private land in Cook County, and large swaths of land across Superior National Forest.

The spongy moth, formerly known as gypsy moth, is an invasive species that can eat the leaves of over 300 different species of trees, according to Kimberly Thielen Cremers, plant pest regulatory and mitigation section manager for the Minnesota Department of Agriculture. Gypsy moths can impact trees through defoliation. In extreme cases, they can kill trees they feed upon, according to state officials.

For decades, the invasive pests were known as gypsy moths. The name was changed to spongy moths to respect various human populations in Eastern Europe, according to wildlife officials who spoke with WTIP.

Spongy moths were introduced into North America almost 150 years ago near Boston. State officials have been successfully detecting and eradicating spot infestations within Minnesota since 1969, according to the Department of Natural Resources. However, both the DNR and Department of Agriculture recognized it was only a matter of time before the moths became permanently  established.

Thielen Cremers spoke with WTIP’s Joe Friedrichs about the 2022 moth survey and what the results mean for the new year. Audio below.

Joe Friedrichs January 9, 2023