As we approach the fly-free date for sowing winter wheat, we need a plan to control our most common weedy pests in this crop. The two most common weeds in our wheat every year are poa and ryegrass. The fall is the best time to control these two weeds in wheat. Continue reading
Some have been concerned about losing dicamba due to court or EPA rulings. Everyone should be more concerned about losing dicamba and 2,4-D to Charles Darwin’s theory. Weeds developing herbicide resistance has caused the loss of many more herbicides than anything a court or the EPA has ever done. It’s not even a close race.
This is particularly true for Palmer amaranth. The newest development is that Palmer amaranth has evolved dicamba resistance here in Tennessee. We are in the beginning stages of Palmer amaranth, yet again, becoming a major problem due to the loss of a herbicides’ utility on that weed. Continue reading
Has Palmer amaranth evolved dicamba resistance in Tennessee? Results from some of the greenhouse experiments this winter and spring as well as in field research this growing season would suggest that our state now has dicamba-resistant (DR) Palmer amaranth. These DR populations are established in Crockett, Gibson, Madison, Shelby, and Warren counties and likely several others. Continue reading
Calls continue from some folks frustrated with goosegrass, junglerice and Palmer amaranth escapes after a dicamba + glyphosate application. A large reason for the frustration is the follow-up applications have often provided less control than hoped. Timing is the cause for some of these poor weed control issues. Herbicide resistance is another cause. Continue reading
Calls continue to come in on concerns about poor Palmer amaranth control after a dicamba application. More than a few have reported that Palmer amaranth has survived multiple dicamba + glyphosate applications (Example above). Continue reading
Some of the earlier planted cotton fields are entering the true “laying it by” application timing. Given the continued reports of Palmer amaranth, prickly sida, barnyardgrass, junglerice and goosegrass escaping glyphosate + dicamba applications going back to an “old school” layby is a good plan.
Some reports have come from folks concerned by the lack of Palmer amaranth response to applications of dicamba plus glyphosate applied in the last 10 days. I expect to get more of these calls as I have seen similar results in our research this spring. Continue reading
The University of Tennessee Weed Tour has been cancelled. Due to the covid-19 virus no large groups are allowed to visit a University research station. Since we cannot have an in-person tour, we plan to post some short videos on the UT Crops News Blog highlighting some of the more interesting research from this summer.