Public enemy No. 1—Palmer amaranth
As you sit in the combine, which provides a bird’s-eye view of the field below, take time now to scout for potential 2017 weed problems.
As you see problem spots that survived herbicide treatments, University of Missouri weed scientist Kevin Bradley making notes to help with next season’s weed programs. And Palmer amaranth, also known as Palmer pigweed, continues to be the weed to watch in Missouri.
The weed continues to spread from the Southwestern United States into the Midwest. It has moved north of the Missouri Bootheel area, which it is the predominant weed species in most fields.
Bradley has been tracking the spread of Palmer amaranth in Missouri since 2009. This season, Missouri fields showed some of the best weed control that Bradley and fellow agronomists have seen.
Nevertheless, Palmer amaranth’s competitive and aggressive nature makes it a bigger threat than waterhemp, the most common pigweed species in the state.
Mature Palmer amaranth often grows to more than 7 feet tall and typically produce about 500,000 seeds per plant. It also is resistant to glyphosate herbicide and is highly mobile.
Palmer amaranth may have made its way into Missouri through contaminated farm equipment from other states. Contaminated hay also acts as a carrier.
Bradley’s research has shown that waterfowl carry seeds for long distances and drop them in fields.
In addition, some states report Palmer amaranth coming in through seeds used for Conservation Reserve Program plantings and in pollinator mixes.
“In short, any seed, feed or equipment coming onto your farm should be thoroughly examined for the presence or even the possibility of Palmer amaranth seed,” Bradley said in a university news release.
For help with identifying weeds, visit the University of Missouri’s online Weed ID Guide or download the companion free ID Weeds app for your smartphone.