A couple of regular readers say they have enjoyed the pigweed articles I’ve written, but have enjoyed about all of them they could stand for a while! I only have a couple more and I will move on to something else.
It is interesting that someone can find a soybean rust symptom — or just something that looks like one — and everyone goes into a panic. However, we continue to drive the Roundup Ready technology off the cliff one year at the time and few seem to notice.
That is not to say soybean rust is not a very serious issue, but weeds will ultimately dictate your production system.
To stop using up modes of action one at the time is going to take a change in the herbicide industry’s “sell what you can now” mentality, a change in the way re-sellers think, and a change in grower use patterns. Unfortunately, I do not see any of those changing anytime soon, but I have the most faith in changing grower use patterns.
The weeds will ultimately dictate what the weed control program will be. However, until we become more proactive managing resistance, we will continue to use up technology one mode of action at the time.
I hear a lot of comments (some from weed science counterparts) along the lines of “even though we have some resistance problems, Roundup Ready will continue to be the centerpiece in our weed control programs.” Is it really if we continue down the same path we are headed?
Palmer pigweed is out of the bottle and that one is going to be hard enough to cork back up.
Marestail continues to be hard to manage in a lot of areas, especially if you want to stay in a conservation tillage system.
Ryegrass resistance has become a huge problem in some areas of Arkansas and Mississippi and that one is going to get worse.
Common ragweed, giant ragweed and johnsongrass resistance have been documented in Arkansas.
Waterhemp resistance has been documented is states where they have it instead of Palmer pigweed.
Next to Palmer pigweed, the weed that concerns me most is barnyardgrass. To my knowledge glyphosate resistance has not yet been documented, but a lot of folks are having a more difficult time controlling it. As genetically diverse as the barnyardgrass family is, I would be surprised if that is not the next weed documented.
Without being critical of anyone, it sometimes seems as if the weed science community is the only one overly concerned about what is slowly happening here.
As we continue to increase the populations of the resistant species we already have and as we continue to develop new ones, how much longer will Roundup Ready be a useful tool? If we get to that, then we have lost the best weed control technology any of us could ever have imagined.
In some ways we are boxed in for the short run as most of the soybean varieties are Roundup Ready. This is a tribute to the success of the technology. However it also means it will be difficult to make wholesale changes on a lot of acres.
We are rapidly heading for a Roundup Ready program based upon conventional herbicides. Conventional herbicide programs were not working well before Roundup Ready, so how can they be the answer now?
In addition, we will continue putting tremendous selection pressure on the system with “cheap glyphosate.”
The way to stop the train wreck from being any worse is to rotate to crops such as corn that are not as dependent on glyphosate and to rotate herbicide modes of action. I am high on the LibertyLink technology because it offers a brand new mode of action with most of the same attributes of a Roundup Ready program.
I am constantly told, “I think I can get one or two more years from my Roundup Ready program. When you get there, then you must begin to use up the next mode of action. The weeds will ultimately dictate the program. You can be much more proactive by dictating the program to the weeds and keep Roundup Ready a valuable technology on your farm for years to come.
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