Herbicides

The bad news? Marestail is a problematic weed lurking in many fields. The good news? There are several control options, according to Kansas State University Extension specialists Dallas Peterson and Doug Shoup.

You or your neighbors could be unknowingly planting Palmer amaranth anywhere Conservation Reserve Program (CRP) mixes are grown or pollinator mixes are established. Palmer amaranth seed in CRP planting mixes have been identified in Illinois, Indiana, Iowa, Minnesota and Ohio. It could be in CRP mixes in other states, too, just not identified yet.

The Environmental Protection Agency (EPA) recently expanded Dow AgroSciences’ Enlist Duo herbicide geography from 15 to 34 states.

Many grasses and annual weed seeds have a relatively short life, two to five years, but researchers are finding other seeds to be more resilient. The Weed Science Society of America (WSSA) recently released a fact sheet with information about weed seed dormancy.

Doctors don’t prescribe treatment without first diagnosing the ailment. Weed control should work the same way.

While all weeds are problematic, waterhemp, marestail, palmer amaranth, giant ragweed and Italian ryegrass are among the worst because they have documented cases of resistance to multiple herbicide groups, which makes them more difficult to control. In addition to resistance, they have the natural ability to evade herbicide control methods.

With one glance at the yellowed soybean leaves at her feet, Audrey Kalil knows exactly what is ailing them.

Stay one step ahead of mounting resistance issues by knowing how to identify and control

Monsanto speaks to investors about its motivation to pursue Syngenta.

In addition to tillage and herbicides, other basic practices can help farmers manage weed seeds.