The development of resistance to foliar-applied PPO herbicides meant that Mid-South farmers could no longer rely on herbicides like Flexstar for controlling Palmer amaranth.

Research shows residual PPO herbicides still offer some level of control, and that’s a positive development for the University of Tennessee’s Larry Steckel.

He discussed those developments in a presentation at The Pesticide Stewardship Alliance conference in Memphis, Tenn., earlier this year.

See Part I: Resistant grasses adding to farmers’ herbicide woes