RESEARCH WORK on glyphosate-resistant horseweed has continued this spring, says Ken Smith, Arkansas Extension weed scientist. “I've put out 15 trials and Extension folk from other Delta states have done the same.”
In July, the researchers plan to meet in Tunica, Miss., to discuss what they've found.
“We want to work together to find what's been tried, what has worked and what hasn't. The meeting will be informal, but it is important.
“We'll all come away understanding what we know collectively. More importantly, we'll know what we don't know and what we need to do to find answers.”
This spring, Smith says, Clarity and 2-4,D have worked well on horseweed. The problem with both products is the waiting period before planting.
“With Clarity, we must spray at least 21 days prior to planting. At about 18 days after an application, we begin seeing horseweed germinating. That means we're forced into two applications before planting. We've got farmers with $25 in herbicide costs before planting the first seed. That's eating us up.”
Weed scientists are running towards horseweed answers “as fast as we can without making serious mistakes.”