Rice growers have options for weeds in Clearfield rice

The acreage of Clearfield rice is going to go up significantly over last year, and I have received several questions about it in the Riceland winter meetings I have attended.

There are a lot of options for controlling weeds in the Clearfield system. I have my favored ways of doing it and others have theirs.

I like applying Command as a pre-emergence herbicide and then making two Newpath applications postemergence. Some ask, “Why use Command when the Newpath is a good grass herbicide?” There are a couple of reasons.

Mainly, I like getting the grass under control from the very start so I am mostly dealing with just red rice with the Newpath program. The other reason is concern over barnyardgrass resistance to the Newpath and Beyond herbicides.

I realize we have a confirmed case of Command resistance in the state. We use so many other herbicides in the Command system, however, I believe it can be managed. On the other hand, if we keep increasing the Clearfield acreage and depend primarily on Newpath and Beyond to do everything, then barnyardgrass resistance could ultimately be a bigger threat to the technology than red rice resistance.

Bob Scott and I have a lot of discussions over the use of the preplant incorporated treatment of Newpath. He favors that treatment where it can be used. I do not disagree. On a silt loam soil in a conventional tillage system, the preplant incorporated treatment can be excellent.

You may get less injury on the hybrids with that treatment. Also, it gives you plenty of time to make one postemergence application of Newpath, then, if there are escapes, apply Beyond before flooding.

However, the majority of Arkansas rice is planted either on heavy soils where incorporation does not work so well or is planted using some form of reduced tillage and may not be tilled prior to planting. It is for that reason I pretty much stick with the postemergence approach, but the preplant incorporated treatment is fine where it can be used.

Bob and I agree that a straight pre-emergence treatment is usually the worst way to go, and I do not recommend it.

A program I like even better than the two postemergence applications of Newpath is one application of Newpath for some residual and switching to Beyond for the second application. The problem is the federal label for Beyond is not yet in place, so it is a non-labeled treatment.

We need a Beyond label that allows those of us in the field to recommend Beyond and Newpath interchangeably based on the situation. Maybe we will get it someday.

On the Clearfield hybrids, RiceTec is recommending no Beyond be applied after panicle initiation as opposed to the 14 days past panicle initiation we had been recommending. This is a situation where early research did not show a problem, but subsequent research after farmer complaints has shown the late applications can injure the hybrids.

The problem this presents is the red rice does not usually canopy out by panicle initiation. By the time it comes out the top, it is too late for the application and you are faced with the decision of whether to take the chance on out-crossing or injuring your rice.

Much of this can be avoided by simply making the Beyond application (after two applications of Newpath to be legal) just ahead of flooding if there any red rice alive or wounded is present at flooding time. I actually like this program better in the conventional Clearfield varieties as well — not for reasons of injury but just better control.

If there is any reason to believe a Beyond application will be needed later when you are doing the final preflood scouting, just do it right then and get it over with. Coverage is much easier and you will have a red rice-free field going to flood and that should get you through.

Next week I will discuss some of the problem weeds in the Clearfield system.

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