Palmer Amaranth Spread to Midwest in CRP Seed

Dec 2, 2016  | 3 min  | Ep4215

Seasonal optimism drives the gift-giving season. All is done with the prospect of putting a smile on someone’s face. However, an unexpected present was delivered to Midwestern farmers earlier this year that is sure to leave more than a frown behind. 

According to university extension scientists, a resilient southern weed has spread more rapidly through several Midwestern states, Iowa in particular, due to the accidental inclusion of the noxious weed in seed blends planted on Conservation Reserve Program land.

The first Palmer Amaranth was found in Iowa in 2013. In the following three years, it was confined to only five counties. By summer of this year, the weed was confirmed in 48 Iowa counties, including 35 associated with nearly 200,000 acres of new CRP land.

Bob Hartzler, Iowa State University, weed scientist: “It wasn’t spreading very rapidly from my crude surveys of the area where it was at prior to this year, but it wasn’t going away either. But now there is no doubt we are beyond eradicating it from the state.”
Mike Witt, regional agronomist, Iowa State University Extension: “I haven’t seen any farmers taking it lightly. They are very concerned about it. But being concerned about it, they know the ramifications that can occur if it leaves their farm and they don’t necessarily want to broadcast the fact that ‘I have it here, here’s the red light’ so that if it moves to somewhere else, then they feel that they might get blamed for it even though it’s not their fault in any way, shape or form.
Weed scientists in Minnesota and Illinois also have confirmed that Palmer Amaranth’s arrival has been sped by its inclusion in seed packets intended to include only native varieties. However, the increase appears to have been less dramatic in those states.
Iowa State’s Bob Hartzler said yield loss is certain for those who fail to keep the plant out of their row crops. In southern states, many farmers are forced to pull and burn Palmer because many of the plants are resistant to one or more herbicides.

Hartzler said the Midwest companies that grow and harvest native seed blends had difficulty keeping up with demand. As a result, he says, the companies mixing the product accidentally included Palmer seed present in flower seeds purchased in Texas and Kansas.

Extension experts began putting the pieces together in late summer. Hartzler and other extension experts said Farm Service Agency officials, who administer the CRP program, should have been more aggressive in getting the word out to landowners.

The USDA told Market to Market in a written statement: “In a limited number of cases, the commercial seed procured by landowners to install conservation covers seems to have been contaminated.  In those cases, USDA has worked with the landowner, extension and local weed experts to address the issue.”
Hartzler said seed testing labs need to improve their monitoring methods to prevent a reoccurrence.

Grinnell Mutual Insurance