Arkansas

Dr. Chuck Wilson, rice specialist with the University of Arkansas Cooperative Extension Service, says the share of acreage planted in Clearfield varieties surged to 14 percent in 2004, up from 4.8 percent in 2003 and 0.3 percent in 2002.

Overall, the technology has worked "fairly well," he says, but in 2004, Mother Nature played havoc with Newpath applications.

Extension weed scientist, Dr. Ken Smith at the U of A's Southeast Research and Extension Center at Monticello, says red rice was "everywhere," especially in northern Arkansas.

"Back in the spring, when it was time to put on our Newpath, the wind was blowing at 30 miles per hour. We knew we couldn't put it on, because it would have drifted onto the cotton and the conventional rice."

But Smith suspects that wasn't the only reason farmers lost some red rice control.

"I think I saw some people last year saying, 'Well, I'm going to go ahead and make my Newpath application now because my barnyardgrass is ready.' Because of the potential to lose Newpath from out-crossing, it's critical that we use it as it was intended, for red rice control."

He's also hoping that farmers will rotate those fields out of rice. If they plant Roundup Ready soybeans, any out-crossed red rice should be controlled by glyphosate.

From the Lonoke Agricultural Center, Smith's colleague, Dr. Bob Scott, says the lack of red rice control prompted the state to seek a 24C "specific use" exemption from the EPA for Beyond herbicide. Beyond, he says, is the same class of chemistry and same mode of action as Newpath. It's a "salvage option" to clean up red rice before the seed heads emerge.

The threat of the Newpath tolerance gene getting into red rice, says Scott, is real. After just two full seasons of commercial Clearfield production, he says, out-crossed plants have already emerged.

Scott recommends proper stewardship, including rotating to Roundup Ready beans and making Beyond applications later "to sustain the technology as long as we can."

For more information, contact your county Extension agent. The Cooperative Extension Service is part of the U of A Division of Agriculture.

Date: 4/21/05