DEPARTMENT DISPATCH

Farmers face many challenges throughout a growing season, including weather extremes and turbulent markets. One of the most urgent challenges we’ve been dealing with over the past several years is the noxious weed Palmer amaranth.

Palmer amaranth is a fast-growing weed native to the southwestern United States and northwestern Mexico. It has now spread east and north. The weed was first discovered in Minnesota in 2016. It has developed resistance to several herbicides, including glyphosate, making it very difficult and expensive to control.

Left uncontrolled, a single female Palmer amaranth plant typically produces 100,000 to 500,000 seeds. It can cause substantial yield losses and greatly increase weed management costs in soybeans and corn.

Because of the costly and damaging impacts that the weed could have on Minnesota’s crops, the Minnesota Department of Agriculture (MDA) has been monitoring for the weed, wiping out any Palmer amaranth plants found in the state and identifying ways to stop the spread of the weed into the state.

The MDA has investigated Palmer amaranth at 94 sites in 22 counties since 2016. Of these sites, Palmer amaranth was found at 34. Farmers and landowners have worked collaboratively with the MDA and the University of Minnesota Extension to control infestations. Control efforts include targeted genetics and herbicides to tackle glyphosate-resistant Palmer amaranth as well as hand pulling and other tools. Our success will depend on each impacted landowner taking action to prevent seed production and spread.

The MDA has also uncovered many ways Palmer amaranth has or can come into Minnesota, including contaminated seed, screenings, manure, and possibly equipment. At this time millet seed, sunflower screenings and manure are the riskiest sources and have led to infestations in the state.

It will take all of us to prevent Palmer amaranth from becoming another waterhemp or worse, gaining a widespread foothold in Minnesota. That’s why we’ve proposed legislation this session to fund grants to local units of government and Tribal nations for noxious weed detection, control and management, including battling Palmer amaranth.

You can also be proactive and prevent the establishment of this weed. Familiarize yourself with Palmer amaranth identification and actively look for it in crop fields, borders, ditches, conservation lands and around dairies.

Avoid entering areas where Palmer amaranth is suspected or confirmed. If you must enter an infested area, always clean vehicles, equipment and clothing prior to exiting. If planting grasses and other flower mixes for conservation plantings, carefully review the seed label to ensure that no noxious weeds are present.

We’ve initiated a campaign to raise awareness, help people figure out how to identify Palmer amaranth, and how to report it to us for confirmation and advice. Visit amaranthaware.com for more information on the invasive weed. We must all work together to stop the spread of this weed into the state.

Thom Petersen, Commissioner, Minnesota Department of Agriculture