Tennessee fields annually turn a purple color around April 1. The weed henbit (Lamium amplexicaule L.) is the main cause for this color. It has distinct purple flowers and is one of the most commonly found plants in our row crop fields. However, there is a close cousin to henbit, purple deadnettle (Lamium purpureum L.), that is also adding to the purple color in many fields. Continue reading
Early Burndown. The challenge to burning down grasses before planting has become increasingly difficult in the last half dozen years. There are two reasons for the sketchy grass control with the traditional burndown application of glyphosate + dicamba. First, the continued evolution of glyphosate resistance in ryegrass, junglerice, johnsongrass and goosegrass have made that “go-to” burndown application inconsistent. Second, we have now documented that dicamba is consistently causing glyphosate to provide poor grass control. As such our recommendation has been to change the “go-to” burndown from glyphosate + dicamba to glyphosate + clethodim.
The problem with using glyphosate + clethodim is that the burndown will miss, or be weak on, some broadleaf weeds, most notably glyphosate-resistant horseweed. During the meeting circuit this winter, several have asked “Is there a herbicide that can be added to glyphosate + clethodim that will provide horseweed control while not sacrificing grass control?” This caused me to go back and examine burndown research we conducted 4 and 5 years ago with Elevore and Verdict. Continue reading
If you haven’t noticed, our UTcrops.com website has gotten a facelift. You may not recognize it when you first visit us at https://utcrops.com/. However, it’s organized similarly to the old version. I’m sure there are a few bugs that need to be fixed, but take a look! This site gives you ready access to essentially all UT resources related to row crop production.
Herbicide resistant traits available in soybean continue to increase. It does not seem that long ago that there was either Roundup Ready or conventional soybean. There are no less than eight different soybean herbicide resistant traits available today with the most recent being XtendFlex soybean. Continue reading
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
If you missed the Corn Inservice webinar, we’ve broken out the five presentations, which are available to view now at the UT Crops YouTube channel.
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