In the Furrow
Report Escaped Pigweeds
By Will Duffie County Extension Coordinator

Recent rains along with warm temperatures have plant growth in full swing. This also includes yield robbing weeds. This flush of growth has Burke County cotton growers busy making herbicide applications to control undesirable weeds.

I urge cotton and soybean growers whom have sprayed glyphosate, known by many as Roundup, in the past week to monitor fields for pigweeds that were not controlled by this herbicide. Many factors contribute to less than desirable control of a weed, but a new type of pigweed is loose in central Georgia.

For years, growers have relied heavily on glyphosate (Roundup) to control this weed. In 2005, Palmer amaranth resistance to glyphosate was confirmed in Georgia. Resistant populations can no longer be controlled by glyphosate at any practical rate, if at all.

To date, Palmer amaranth from 136 fields throughout middle Georgia has been evaluated for resistance to glyphosate. Glyphosate resistance in Palmer amaranth has been confirmed in 71 of these 136 fields in the following counties in Georgia: Taylor, Macon, Dooly, Sumter, Crisp, Lee, Wilcox, Turner, Ben Hill, and Colquitt.

This weed is such a problem because 1 pigweed plant per 20 row feet of cotton can reduce yield at least 7%, and a single female plant can produce 500,000 seeds. Please take the time to monitor fields and report suspect plants to the Extension Office. For more information contact the Burke County Extension Office at (706) 554- 2119.