Control Options for Palmer Pigweed
The topic of Palmer amaranth, or Palmer pigweed, control was recently brought up by a North Carolina caller in a Syngenta-sponsored episode of RFD-TV Live! A lack of control options coupled with an easily replenished weed seedbank, a fiercely competitive nature and the potential for hybridization makes the spread of glyphosate-resistant pigweed a relentless threat in many Southern states.
In Arkansas, there are more than 3 million acres of soybeans and 95 percent of those are glyphosate tolerant; receiving an average of 1.75 in-crop glyphosate applications each year. With few other herbicides applied, burndown applications of glyphosate used and rotating with other glyphosate-tolerant crops, there is a great deal of selection pressure placed on weed populations.
Using the Solution Builder available on resistancefighter.com, the following recommendations were made for a soybean grower in North Carolina facing glyphosate-resistant Palmer pigweed.
- Apply Gramoxone Inteon® tank-mixed with phenoxy (2, 4-D) plus Boundary® applied pre-plant burndown or pre-emergence followed by a post-emergence application of Flexstar® tank mixed with Touchdown® (glyphosate).
- Rotating the crop to rice is another good management strategy. If you do this, you must take care to control pigweed escapes around the edge of the field and on the levees as well.
- If you suspect a field has resistant pigweed, always clean your equipment when moving from that field to another area.
Has Palmer pigweed become a larger problem in your area like it has for so many Southern growers? How have you addressed it? Where did you turn for information?
Important: Always read and follow label instructions before buying or using these products. Boundary®, Flexstar®, Gramoxone Inteon® and Touchdown® are trademarks of a Syngenta Group Company.
A Palmer pigweed plant.