Palmer Amaranth Management in Texas High Plains Cotton

Palmer amaranth has been the most common problem weed in Texas High Plains cotton for as long as the crop has been produced in this region.  Preplant and preemergence herbicides in combination with tillage and hand labor were effectively used for many years.  With the development of Roundup Ready cotton, Palmer amaranth was effectively controlled with less reliance on cultivation and residual herbicides.  Producers in this region have continued to use preplant incorporated dinitroaniline herbicides with glyphosate postemergence.  Residual herbicides such as metolachlor, pyrithiobac, or pendimethalin are commonly tank-mixed with glyphosate.  No instances of glyphosate resistant Palmer amaranth have been documented to date.