Over the past month, I’ve visited with several researchers and many growers and retailers about weed resistance at industry trade shows and meetings. I’ve heard quite a bit about the state of glyphosate resistance across the country, so as we head into spring, there is plenty to keep in mind.
Most growers would be thrilled to control 98% of the weeds in their fields and, in most cases, that means a job well done. But in cotton country, Dr. Jason Norsworthy, University of Arkansas weed scientist, reports that this may not be good enough. He says an explosion in glyphosate-resistant Palmer pigweed means that pressure is so heavy that even 98% control is unacceptable. He recommends a season-long weed management program to protect crops from Palmer pigweed competition from pre-plant through harvest.
Another University of Arkansas weed scientist, Dr. Nilda Burgos, agrees. She says studies show that if you allow the weed to compete with cotton early in the season, it can really hurt yield.
Resistance Fighter of the Year Paul Barchenger commented during a panel at Commodity Classic that despite the low cost of glyphosate this year, growers need to be careful.
Not controlling weeds early in the season can actually cost them more in yield in the long run. He encourages growers to include residual herbicides and multiple modes of action to control weeds and protect crop yields.
And grower Mike Flanary, who also participated in that panel, said that the effort required to proactively manage weed resistance is not much more than what he does anyway. He believes protecting his crop and managing against resistance for future seasons is worth a bit of extra work today.
What weed resistance questions or concerns are on your mind heading into spring?