Invasive Palmer amaranth discovered in Houston County

After positively identifying invasive Palmer amaranth plants in Houston County, state agriculture officials are investigating the source of the infestation.

Houston County’s agriculture inspector discovered several hundred of the plants in a small hay field, according to a statement released Thursday by the Minnesota Department of Agriculture. The field was mowed and burned off to destroy the plants and its seedlings. The department said it will monitor the site and officials encouraged farmers across the state to monitor their fields.

“While we’re still trying to determine how Palmer amaranth got into the field, we’re asking farmers to scout for the weed now before harvest,” said seed unit supervisor Denise Thiede. “The plants will be identifiable with flowering and fruiting structures.”

Palmer amaranth has been found in eight Minnesota counties since it was first discovered in Lyon and Yellow Medicine county conservation plantings in 2016. As recently as August, the weed was discovered in a millet field in Lincoln County.

The plant, which can grow to up to eight feet tall, can damage crops by crowding them. Common herbicides are often ineffective in destroying it. It’s listed as an “eradicate” weed on the Minnesota Noxious Weed list, and its seeds are prohibited in Minnesota and surrounding states.

Infestations have cost farmers in other states millions of dollars, prompting state agriculture officials to take a zero-tolerance approach to the invasive weed. The agriculture department will monitor infestation sites for up to three years and encourages anyone who finds the plants to contact the department’s tip line or a local crop consultant.

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