Michigan Releases Weevils to Control Invasive Mile a Minute Weed

By Andi Anderson

Michigan is taking a new step in controlling invasive plants by releasing tiny weevils to fight the mile-a-minute weed. This fast-growing vine is known to spread quickly and damage natural habitats as well as agricultural land.

The project will begin on June 18, when several thousand weevils are released at four locations in Calhoun County. Each site will receive around 1,000 weevils. These insects are being used as a biological control method to reduce the weed’s population naturally.

The mile-a-minute weed is not native to the region and grows very quickly. It can reproduce many times in a year and even survive through winter. This makes it a serious threat to forests, farms, and wildlife habitats. It can also spread into hayfields, orchards, vineyards, and Christmas tree farms, causing economic losses for farmers.

“Mile-a-minute weed is not native. It meets the definition of an invasive species, right, which is two parts, it is not native and it causes harm,” said Grzesiak. “It lives up to its name, it grows very, very quickly and it is able to reproduce multiple times in a year, as well as over winter, so it can be a really big problem.”

The weevils being used are small beetles that feed on the weed. This method has already been used in the United States since 2004 and is considered safe. Experts have tested the insects carefully and found that although they may feed on other plants, they cannot reproduce on them. This ensures that their population will naturally decrease once the weed is controlled.

“This is much more of a research opportunity. We are trying to find out if this biological control, which is approved by the USDA, could be a good tool in our tool box,” said Grzesiak.

The project will be closely monitored for about one year. Experts will check plant damage, changes in weed growth, and the number of weevils every two weeks.

“We actually didn’t do any determination of that, that came from the supplier. They said we ship these in amounts of one thousand,” said Grzesiak.

Officials are encouraging the public to help by reporting invasive species and managing them when found.

“Folks anywhere in Michigan can get involved with invasive species. Any invasive species is worth taking note of and managing if it is on your property, or reporting on the Midwest Invasive Species Network,” said Grzesiak.

This effort highlights the importance of using safe and sustainable methods to protect agriculture and the environment.

Photo Credit: gettyimages-dmaroscar