July 8, 2021

The Minnesota Department of Agriculture (MDA) is preparing to treat areas in Carlton, Lake, and St. Louis counties to slow the spread of a gypsy moth. Officials will conduct the aerial treatment July 13-16, beginning as early as 6:15 a.m. each morning and continuing throughout the day. The dates and times are dependent on weather conditions in the area.

The sites total approximately 64,600 acres. They are:

  • Carlton and St. Louis counties – Esko block, including portions of the city of Duluth – 19,839 acres (MAP)
  • Lake and St. Louis counties  – French River block, including portions of the cities of Duluth and Two Harbors – 44,847 acres (MAP)

Residents can look up their address on an interactive map to determine if they are within either of these blocks.

The MDA will use a method of mating disruption involving the aerial application of an organically certified, waxy, food-grade substance containing pheromones specific to gypsy moths that confuses the male moths. This makes it difficult for the male gypsy moths to find females for mating, which means reduced mating success. The result is fewer caterpillars hatching and attacking trees next year. Application is timed just as adult moths emerge in early summer.

The mating disruption product will be applied by low-flying yellow planes contracted by the U.S. Forest Service in a joint project with the MDA. These planes fly approximately 150 feet above the treetops and will be traveling outside the treatment areas as the planes navigate through the gypsy moth infestation sites. The product is not harmful to humans, animals, birds, or other insects, and will help protect forest health, property values, and the state’s tourism industry.

To help area citizens stay informed, the MDA has set up an Arrest the Pest information line at 1-888-545-MOTH (6684). The hotline will offer the latest details about treatment dates and times. Residents can sign up for updates about treatment progress by texting “MDA NORTHEAST” to 468311 to receive text notifications or texting “MDA NORTHEAST [your email address here]” to 468311 to receive email notifications.

Gypsy moths are among America's most destructive tree pests, having caused millions of dollars in damage to Eastern forests. The moths are now threatening Minnesota. If present in large numbers, gypsy moth caterpillars can defoliate large sections of forest. Oak, poplar, birch, and willow are among their preferred hosts. The moths spread slowly on their own, but people can unintentionally help them spread by transporting firewood or other items on which the moths have laid their eggs.

Contact the Minnesota Department of Agriculture at 1-888-545-6684 or Arrest.the.Pest@state.mn.us with questions regarding gypsy moth and the planned treatment.


Media Contact
Allen Sommerfeld, MDA Communications