I have been asked on several occasions by Clearfield rice growers “how can I best avoid having to make a late season Beyond application?” It does seem as if more acres need to be treated with Beyond, following two applications of Newpath, than I thought there would be. Sometimes red rice pressure simply dictates the need for three treatments.
I have written articles about fields in which I have been involved in making the recommendations that needed three applications. In these cases the red rice pressure was horrendous and each Newpath application provided 95 percent or better control. However, there were plenty of escapes to require the Beyond.
In other situations, a Beyond application is needed when one or both of the Newpath treatments fail for some reason. Sometimes incorrect management decisions result in a treatment failure. Sometimes weather conditions make things difficult or cause you to make a wrong decision.
The weather sure did not cooperate last year. In other cases, you can do everything right and the treatment just does not work.
Red rice is a very persistent pest and trying to achieve 100 percent control of any weed with any herbicide program is very difficult. However, I believe some types of Clearfield programs give you a better chance of achieving control with the two Newpath applications than others.
In research plots, programs that use one soil applied application of Newpath followed by one post-emergence application perform equal to those using two post-emergence applications. However, in the field, I see a different result.
I see a lot more failures with the programs that use a soil application than with the total post-emergence programs. The difference between research results and field results are due to water management in most cases. Small research plots are easy to flush timely.
Last year in the field it was not easy to flush anything timely. When the soil applied treatment fails then the red rice pressure will overpower the remaining Newpath post-emergence treatment. Soil treatments that are applied pre-emergence or on the soil surface will fail more quickly without activating moisture than an incorporated soil treatment will.
However, even with the preplant incorporated treatments, I see a lot of inconsistency in the field. When the soil applied treatment works, it is nice. You have bought some time and it is one less treatment you have to worry about with around emerged susceptible crops.
However, if you are using the soil applied treatment because of drift issues on later emerging crops, remember you have those same issues with the Beyond treatment if the soil applied Newpath treatment fails. The problem is that when the soil-applied treatment fails due to lack of moisture, it fails completely.
The two-shot post-emergence program is not foolproof either. However, I find it much more consistent. With the post-emergence treatment, the main thing that will cause it to fail is drought stressed red rice. If it is stressed the other rice is also and needs flushing.
You can usually always time the post-emergence treatment to some soil moisture. If there is moisture, the Newpath application will normally kill the red rice that is emerged. Even if you fail to get a rain or flush to activate the residual component, you have killed one flush of red rice.
I believe the Clearfield program that has the best chance of avoiding a Beyond application is one that you apply Command as a pre-emergence herbicide to get the jump on grass control. Then time the first Newpath application to 2 to 3-leaf red rice.
If there is good soil moisture, that is great. If not, flush it first. I do not worry too much about activating the residual on the first application because you will be following with the second application soon. Then, time the second application just ahead of the flood.
This program will sometimes also require a Beyond treatment, but I feel it gives you the best chance of avoiding it.
Ford Baldwin, Practical Weed Consultants. e-mail: firstname.lastname@example.org.