June 21, 2022

The Minnesota Department of Agriculture (MDA) is planning to treat two areas in Cloquet and Duluth to eradicate gypsy moth (now known as spongy moth) infestations detected in those areas last fall. Officials plan to conduct the treatments on Wednesday, June 22. The aerial treatments will start as early as 5 a.m. in Duluth followed by Cloquet. It may take up to two hours to complete both areas.

The Duluth site is approximately 75 acres in the New Duluth Neighborhood, from 98th Ave. W to the railroad tracks and extending from Bowser St. to near Minnesota Highway 39. The Cloquet site encompasses approximately 500 acres around the Sappi mill property, including the area near the St. Louis River and Cloquet Ave. The low-flying airplane will be traveling up to a half mile outside these treatment areas as it navigates through the insect infestation sites. The MDA apologizes for any inconvenience caused by the noise of the plane.

This is the first of two aerial applications of Foray/Bacillus thuringiensis var. kurstaki (Btk) over each area. The second will take place in 5-14 days. Btk is a biological product that is organic certified for food crops. It has no known health effects for humans, pets, birds, fish, livestock, bees, and other non-caterpillar insects.

To help area citizens stay informed, the MDA has set up a Report a Pest Info Line at 1-888-545-MOTH with the latest details about treatment dates and times. On the morning of the treatments, residents can call the phone number with any questions they may have. Simply press 0 (zero) to speak to someone. The MDA's website (www.mda.state.mn.us/gmtreatments) also has information about gypsy moths and control efforts. Residents can sign up for updates about treatment progress by texting “MDA MOTH” to 468311 to receive text notifications or texting “MDA MOTH [your email address here]” to 468311 to receive email notifications.

The MDA offers the following tips to residents in the treatment area:

  • For the gypsy moth treatment to work, it must begin early in the morning. Treatments may begin as early as 5 a.m. Residents in and around the treatment area, up to a half mile outside of the treatment area, may be awakened on that day by the noise of a low-flying airplane. The MDA apologizes for any inconvenience.
  • The treatment product has no known health effects for humans, but residents may wish to stay indoors during the treatment and keep windows closed for a half hour after application. Residents can cover gardens or turn on sprinklers during the treatment if they wish.
  • The residue does not cause damage to outdoor surfaces. However, soapy water will remove any residue on outdoor items.

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 reportapest@state.mn.us with questions regarding gypsy moth and the planned treatment.

Gypsy Moth Name Background

As of July 2021, the Entomological Society of America (ESA) discontinued the use of “gypsy moth” as a common name for Lymantria dispar. A new common name, spongy moth, was selected by the ESA on March 2, 2022. The Minnesota Department of Agriculture will begin phasing out the discontinued common name and adopting the new common name over the next year in accordance with state and federal regulations.


Media Contact
Allen Sommerfeld, MDA Communications