Minnesota finds source of invasive weed on conservation land

Infestations of the weed, Palmer amaranth, have affected other states in the U.S. Midwest through seed planted on land in the federal Conservation Reserve Program, weed scientists have said.Palmer amaranth, which is native to the Southwest, has spread across conservation land in Iowa, which accounts for nearly a fifth of U.S. corn production and in 2016 exported more than $1 billion of corn and soy.Infestations of Palmer amaranth, which can grow as much as 2 inches a day, spread over 30 planting