Barnyardgrass Battles: One Size Doesn't Fit All
Weeds are emerging in fields where water has recently come off, with barnyardgrass leading the charge. Each field is different, so there's no one-size-fits-all solution. If weeds are up but rice hasn’t emerged, glyphosate (alone or with Command) is a good option.
A few calls are already coming in on emerged barnyardgrass along with other weeds in fields that went under water, and now the water is off. Each field will likely be a unique situation, so it is impossible to make blanket recommendations. However, Dr. Jason Norsworthy and I have been trading thoughts and ideas on options to consider. One scenario could be there are emerged weeds but no emerged rice. In that case, apply glyphosate or a glyphosate plus Command mixture BEFORE any rice emerges. Most of the situations will have emerged from rice. Some calls have been on emerged barnyardgrass and some have included annual sedges. If aquatics have not emerged yet they will be coming.
My philosophy is to focus on barnyardgrass first and pick up the other weeds if you can. Often, the calls include concerns over sick, yellow, or stretched rice. One treatment that is effective on small barnyardgrass and easy on the rice is Clincher, and a Clincher plus Command mixture can fit nicely into some of those situations. It won’t get the annual sedges or emerged aquatics, but those can be picked up later. If your tolerance for burn is higher, and you have a stand of rice, RiceBeaux plus Command can be a good all-around treatment on small barnyardgrass, aquatics, and annual sedges.
Until you are certain no replanting will be needed, the use of any thiobencarb (Bolero, RiceBeaux, etc.) products is discouraged. If none of those treatments strike your fancy, just hit it with a gallon of propanil (with Command) on an 80-degree day and see what is left. While that will clean up a lot of junk, it may just leave you with propanil-resistant barnyardgrass. However, by then, the rice should be healthier, and more aggressive treatments can be used. In addition to the options mentioned above, if the rice is FullPage, the first Preface or Postscript can be included in the mix. On Clearfield rice, we like to see green rice and new roots before the first Newpath application.
If the weed problem is primarily annual sedges and aquatics, propanil plus Basagran is an excellent treatment. A lot of these situations may occur before any soybeans have emerged in close proximity, and if so, Loyant can be a great fit.
We have recommended Command in all of the options to get some barnyardgrass/ sprangletop residual going. If it doesn’t rain within a few days after application, add another residual in front of a predicted rain, or perish the thought of a flush!
These are just a few ideas. Myself, Dr. Norsworthy, Dr. Barber, and Dr. Scott are always happy to consider your individual situation and help in any way we can.
More Ford Says
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Ford Says: Command Injury
A phenomenon observed more than usual this year is very defined (and often severe) injury patterns in some fields from clomazone or Command. While it is not uncommon to see old levee patterns, planter patterns, wheel track patterns, tillage patterns, and some soil residual herbicide applications, some of these with clomazone this year seem much more pronounced than usual.