Barnyardgrass in Clearfield rice

I recently had the opportunity to hear Ken Smith’s presentation on herbicide resistant weeds in Arkansas. He and the other weed scientists at the University of Arkansas have established what I consider to be the best educational program anywhere on herbicide resistance management. Their approach is totally unbiased and tells it just like it is.

I think farmers are more interested in hearing about herbicide resistance now, but I still do not see enough folks willing to make the changes necessary to prevent it. I have said many times before and will say it again: with a technology like Roundup Ready that has changed the entire way you farm, how can you gamble? You will be much better off preventing resistance than fighting it after you get it.

If we do not do a better job of preventing barnyardgrass resistance in rice, we are not going to have anything to fight with.

Ken has an honest down-home approach to resistance management that every farmer should hear — not only hear it, but please implement the practices he suggests. We can still avoid the train wreck I see coming with both the Roundup Ready technology and our weed control programs in rice.

The key to holding weed control costs down in both Clearfield and conventional rice is to keep as much barnyardgrass as possible from emerging. I talk a lot about $50-per-acre herbicide programs versus $100 programs. Some of this comes from my own observations and discussions with the consultants that call me regularly.

However, the real documentation is in the University of Arkansas Rice Verification program. Chuck Wilson says that in 2008 they had $50-per-acre herbicide costs in verification fields, $100 and up costs in others and not much in between. The difference was whether or not a pre-emergence herbicide was used and activated.

Once barnyardgrass gets out of the ground and growing, it is becoming harder and harder to kill. You can spray a postemergence herbicide and get 80 percent of it, spray it again and get 80 percent of what is left and still cut a grassy rice crop.

In both conventional and Clearfield rice I recommend starting with Command pre-emergence or Prowl plus Facet or Quinstar delayed pre-emergence. The Prowl plus Facet or Quinstar program is excellent but requires more water management to make it work consistently. I really like the treatment in its place with growers who know how to make it work.

In most cases however, the residual treatment of choice will be Command. It still offers the most bang for the buck, even though the bucks have gone up in the rice herbicide market. In conventional, rice consider coming back with Facet or Quinstar in front of the next rain behind the Command, but before any grass emerges. You can also add some more Command in to these as a split shot.

If you did happen to use the Prowl plus Facet or Quinstar delayed pre-emergence, consider some Command behind it before any grass emerges. There are a lot of possible combinations, but the point is to hit it twice before you ever see it.

In Clearfield rice behind the Command, hopefully you will have some emerged red rice shortly thereafter and get the first Newpath out in front or a rain. If any barnyardgrass has emerged, add some Facet, propanil, RiceBeau or something to it to make sure you don’t miss.

You may be thinking, “That is a lot of money before I see any grass.” I agree, but after you see the grass you will likely spend a lot more and still not get it all. I have shifted my concern in Clearfield rice to getting the barnyardgrass rather than being so focused on red rice.

I still have people come up to me, take out their cell phones and ask, “Now which one of these numbers is the right one?” Get all of them out of your phone but one — (501) 681-3413. That is the only number I have and you are welcome to call it. I look forward to the season.

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TAGS: Rice
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