Agriculture officials in Montana are urging landowners to look out for an invasive weed recently found in Cascade County. In August 2026, a small patch of Palmer amaranth was confirmed for the first time in a local fallow field, marking the sixth confirmed occurrence of the weed in the state.
Both Palmer amaranth and its close relative, water hemp, pose severe threats to Montana agriculture due to their resistance to most common herbicides. If these weeds become established, they could cause a major economic impact on warm season crops like corn and millet, alongside irrigated sugarbeets, cereals, and pulse crops.
If you suspect you have spotted Palmer amaranth or water hemp, do not pull the plant. Take photos, record the GPS coordinates, and immediately report the sighting to the MSU Extension Hill County Office by calling 406-400-2333 or emailing hill1@montana.edu.
