Arkansas weed control

With the warm weather in early April, a lot of rice was planted a week or so earlier than normal. The weather conditions involved have generated a lot of weather-related questions. Perhaps I can best summarize a lot of them by recommending you scout early for grass and if you have it, kill it.

A lot of the Command applied on early rice was out at least a week, and often longer, without any rainfall for activation. This again proves what I say every year, growers are not going to flush to activate a herbicide if they have enough soil moisture to get a stand of rice without it.

Some rain (from a little to a lot, depending on the part of the state) has fallen, so we get the questions on “reach-back effect.” That is, will the Command, once activated, pick up the small grasses that emerged before activation occurred. The answer is sometimes, but you can't count on it.

If it turns white, stops and goes into reverse, watch it for a while. If it has a green new leaf and is growing, kill it.

I feel a lot of Command fields will need spraying for escaped grass much earlier than last year. The folks that got the light rains are asking, “How much does it take to activate Command?” On clod-free ground that is packed with a roller, the answer is almost any shower will do it. On a fluffy or cloddy seedbed, it takes enough rain to melt things together.

The week before Easter, when much of the rice in the central part of Arkansas was planted, the wind was a gale at daylight and got worse during the day for most of the week. Some growers gave up on trying to apply Command and pulled their levees. In those fields, a lot of the program will switch to Facet.

The economics on the Prowl plus Facet delayed pre-treatment look good. The state-recommended reduced rate of 0.25 pound (product) of Facet is hard to beat for the money, compared to labeled rates on a silt loam soil. On fields with emerged grasses, the recommended reduced rate of Facet mixed with propanil is an excellent choice.

In Command fields where the grass breaks early, that 0.17-pound rate of Facet with propanil will get you to flooding in most cases.

The big issue with growers who have grass breaking early behind Command is how to avoid having to make a third application across the field. Some early residual help from Facet may be the key.

Some will be looking to Ricestar for postemergence grass control. Remember, it is not a salvage herbicide. Scout and spray two- to three-leaf escaped grass.

The early planting, followed by the rains, reduced early applications of Command by air in our four-county research area. We couldn't start until April 14 and a lot of the rice had either been sprayed with ground equipment or had emerged grass and folks were switching to Facet. Hopefully we will pick up enough of the later-planted rice to be able to make a decision for next year.

I pay high compliments to the aerial applicators I have observed that put their airplanes through our Extension agricultural engineering certification for Command. The setup that people are using to apply the Command is getting the fine droplets and wingtip varieties out of the pattern. That is what we should be running to apply all herbicides.

I heard that a few did not certify their aircraft because they did not want the expense of re-certifying farms or the expense of the new nozzle technology. I challenge every applicator to do it whether or not you ever fly any Command. If it eliminates one complaint, the cost has more than been justified.

Ford Baldwin is an Arkansas Extension weed scientist.

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