Invasive weeds found in Winona County

Invasive weeds make yet another first appearance in southeast Minnesota. The Minnesota Department of Agriculture (MDA) has positively identified the invasive weed Palmer amaranth in Winona County.

Invasive Weeds
It’s official. Palmer Amaranth has made its first appearance in Winona County down in southeast Minnesota. (Photo from MDA.org)

The MDA was contacted by crop consultants after they discovered several suspect plants in a soybean field. MDA staff scouted the area and removed 20 Palmer amaranth plants, which were then confirmed as Palmer by genetic testing. The field has since been treated with a herbicide application, and follow-up scouting by the MDA did not find any new invasive weeds. The site will be monitored for three years for any new Palmer amaranth.

The MDA is trying to determine the source of the invasive weed.

Now is the time when Palmer amaranth becomes visible in agricultural fields. The MDA is asking farmers, crop consultants, and agronomists to report any suspicious plants to the Minnesota Department of Agriculture’s Arrest the Pest line at 1-888-545-6684 or arrest.the.pest@state.mn.us.

If you’re one of the fortunate ones who haven’t seen Palmer Amaranth show up in your fields, here’s a quick refresher on identifying the plant, courtesy of Purdue University.

Since it was first discovered in the state in 2016, Palmer amaranth has been found in nine Minnesota counties, including Winona County. Details of previous finds can be found on the MDA website.

Palmer amaranth is listed as a noxious weed in Minnesota. All above and below ground parts of the plant must be destroyed, and it cannot be moved. The weed is also listed as a prohibited weed seed in the state. This means no Palmer amaranth is allowed in any seed offered for sale in Minnesota.

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

MDA Issues Advisory on Cover Crop Seed

Minnesota Seed Law must be followed on prevented planting acres

Minnesota farmers may be in the market for more cover crop seed than in previous years. Poor planting conditions this spring are forcing some farmers to make decisions on prevented planting. The Minnesota Department of Agriculture (MDA) wants to remind farmers about the legal requirements for selling and buying seed in Minnesota, which does include cover crop seed.

Cover crop seed
More acres might be going into cover crops because of prevented planting conditions. The Minnesota Department of Agriculture has some reminders when farmers are looking to buy cover crop seed. (Photo from AgNook.com)

MDA says it has seen several issues in past years that violate Minnesota’s Seed Law. Buying grain from an elevator for the purpose of sowing is not legal. It is also illegal to brown bag or sell grain out of a bin. Furthermore, all seed sold in the state must be labeled.

“Minnesota’s Seed Law restricts these activities for numerous reasons, ” said Denise Thiede, MDA’s Seed Unit Supervisor. “Farmers could be bringing in weeds through unlabeled and untested seed, or they may not be get the type or quality of seed they paid for.”

In addition, almost all seed varieties have some form of intellectual property protection that restricts the use and sale of the variety under the federal Plant Variety Protection Act. Violating this act can lead to significant fines for both the seller and the buyer.

If farmers are buying seed to sow on their land, the MDA offers the following advice:

  1. Make sure the seed has a label.
  2. Confirm the cover crop seed has been tested for noxious weed seeds, including Palmer amaranth.
  3. Make sure that it is a legal sale by asking the seller if they have the legal authority to sell the product.
  4. Ask about the variety of seed. A variety protected by the Plant Variety Protection Act must be sold by variety name and may be required to be sold as a class of certified seed.

More information on the requirements for selling seed in Minnesota can be found at on the MDA’s website (www.mda.state.mn.us/seed).  

More Palmer Amaranth appearing in SW Minnesota

The Minnesota Department of Agriculture (MDA) is investigating the source of a Palmer amaranth plant found growing in Jackson County.

Palmer Amaranth
Palmer Amaranth is popping up in southwestern Minnesota counties, including Redwood and Jackson. Keep an eye out for this in your fields. If you do find it, get out there and pull it out by hand, including the roots. Don’t let it multiply! (Photo from NRCS/Iowa)

In early September, a farmer noticed a suspicious weed in the first few rows of a soybean field adjacent to a utility field road. The weed survived a herbicide treatment. making initial identification difficult. The farmer then contacted the University of Minnesota Extension, which submitted the plant for genetic identification. The test has confirmed it was Palmer amaranth. MDA staff scouted fields in the area and have not found any other Palmer plants. The MDA is investigating where the Palmer amaranth seed came from.

“This is another case illustrating the effective collaborations established between the MDA, U of M Extension, crop consultants, and farmers throughout the state for locating and reporting Palmer amaranth,” said Mark Abrahamson, MDA’s Director of Plant Protection. “We continue to urge farmers and landowners to become familiar with what Palmer amaranth looks like and to immediately contact the MDA, Extension, or a crop consultant for help if they suspect Palmer amaranth on their property.”

Since 2016, the invasive weed has now been found in six Minnesota counties. In addition to this latest find in Jackson County, the MDA confirmed the weed in a Redwood County soybean field last week. It was also discovered in conservation plantings in Lyon and Yellow Medicine counties in 2016, and Todd and Douglas counties in 2017. However, after eradication treatments, Palmer has not been found at any sites in those four counties during 2018.

Palmer amaranth is listed as a Prohibited Weed Seed. This means it’s not allowed in any seed offered for sale in the state. It is also on Minnesota’s Prohibited Noxious Weed Eradicate List. All above and below ground parts of the plant must be destroyed. Also, no transportation, propagation, or sale of this plant is allowed.

If anyone suspects Palmer amaranth, they can contact the MDA through the Arrest the Pest line at 1-888-545-6684 or arrest.the.pest@state.mn.us.

Palmer amaranth is native to the southwestern United States and northwestern Mexico. It has been found in over half of the states, and along with Minnesota, it has been found in the neighboring states of Iowa, North Dakota, South Dakota, and Wisconsin.