The Minnesota Department of Agriculture is proposing another round of aerial spraying of Btk in areas in and near Duluth in an effort to control gypsy moths. This will be the third aerial spraying in recent years ("State plans gypsy moth treatments in Duluth, Lake County," Feb. 17).
While Btk will kill gypsy moth larva, it is also known to kill other larva, including monarch butterfly caterpillars.
This is while citizens of Duluth are helping Duluth become a more monarch-friendly city. Certified monarch way stations are found throughout the city, and only Minneapolis has more. Mayor Emily Larson has signed on to the National Wildlife Federation Mayors' Monarch Pledge.
Aerial spraying of Btk in Duluth will be a step backward in making Duluth more monarch-friendly. Pheromone treatments and Gypchek are other treatments used to control gypsy moths and do not have lethal side effects to other caterpillars.