Palmer Amaranth Found in Fourth Minnesota County
Palmer amaranth continues to spread through conservation plantings in Minnesota. The Minnesota Department of Agriculture (MDA) has confirmed a new Palmer amaranth find in Douglas County. The invasive weed has also been detected in the central Minnesota county of Todd, and the southwestern counties of Lyon and Yellow Medicine.
The Douglas County infestation was found through MDA’s investigation into a Palmer amaranth find in Todd County. That investigation is still ongoing as MDA searches for the source of the weed seed.
“It is fortunate that we are finding these infestations early on,” said Geir Friisoe, the MDA’s director of plant protection, in a news release. “Through early detection, we can develop an effective eradication plan and manage these small, isolated sites before the weed spreads beyond the plantings.”
All Minnesota infestations have been found in conservation plantings. None of the weeds have made their way into row-crop fields, which could be economically harmful, say MDA officials.
Palmer amaranth can cause substantial yield losses and greatly increase weed management costs in soybeans and corn. Data collected by Purdue University researchers show this weed can ravage yields by 78% in soybeans and by 91% in corn.
Iowa was the poster boy for Palmer infestations via conservation plantings in 2016. It was a major reason last March that Palmer amaranth infested 49 of Iowa’s 99 counties. http://www.agriculture.com/crops/pesticides/palmer-amaranth-bedeviling-farmers-like-no-other-weed
This mimicked what happened in Ohio and Indiana in previous years.
“One way it came into Indiana was through pollinator habitat seedings,” said Purdue University’s Bill Johnson in our story.
Good news: Minnesota has been way ahead of the game when it comes to declaring Palmer amaranth a noxious weed. It is illegal to sell any seed in Minnesota that contains Palmer amaranth. Dealers must test seed lots before putting them on the market. Proper seed labeling laws must also be followed.
“To help curb the spread of this weed, landowners should buy seed mixes from reputable seed dealers,” added Friisoe in the news release. “You should ask the dealers to see the blending paperwork and lab certification results.”
The MDA is having success in eradicating the 2016 finds in Lyon and Yellow Medicine counties. A small number of weeds were found this year, a major decline when compared with the initial discoveries last fall.