Cotton farmers will be looking at new technology they hope will increase weed control efficiency in 2006 but, even with Roundup Ready Flex, they must continue to manage much as they have in the past.
“If we let weeds go early in the season, we get competition that may not become evident until late,” says Texas A&M Extension cotton specialist Robert Lemon, who discussed the new technology during the Beltwide Cotton Conferences in San Antonio, Texas.
“Farmers still have to manage weeds as they have in the past,” Lemon said during a panel discussion of new technology at a Beltwide Cotton Genetics breakfast seminar. “We are a little concerned that growers will wait too long to get that early application on cotton.”
Roundup Ready Flex allows for over-the-top applications of Roundup much later in the season than was possible with Roundup Ready varieties.
Lemon says farmers need to assure eight to 10 weeks of weed-free cotton to prevent yield loss from weed competition. “Flexibility is the key with Roundup Flex varieties,” he says. “Also, farmers should continue to use a residual herbicide. Those materials will continue to play an important role in weed control even with Flex.”
Lemon says growers improve chances for better weed control with residual herbicides and also lessen the potential for resistance. He says marestail has been troublesome in many parts of the country but that Palmer pigweed may be just as much a threat in Texas.
“We have to use alternative chemistries to maintain our technology,” he says.” Liberty Link will also play a role.”
Bobby Byrd, who raises cotton near Hale Center, Texas, says residual herbicides remain an important part of his weed control strategy. “When Roundup Ready first came out I eliminated Caparol and Cotoran. I've put those back in and sometimes use Karmex with a hooded sprayer.”
Byrd says he's seen some marestail infestations and will use the best system he can to prevent a severe problem. He's also considering backing away from no-till cotton for a while on some of his pivot-irrigated cotton.
“I'll plow down some beds and plant flat,” he says. He's also looking at 2-4,D and other options, “including plowing,” to control marestail.
Lemon says the system has looked good in trials. A plot in the Texas Upper Coastal Bend last summer went in late, May 3 as opposed to the optimum April 1 planting date.
“We saw a lot of grass and day flower pressure,” he says. “Day flower is tough to kill, even with Roundup. We applied Roundup at the four-leaf stage and with the old Roundup Ready system we would have been in trouble. But 10 days after we made the initial Roundup application, we sprayed again and made a third application later in the season. We had good control and were able to use the highest labeled rates over the top. We saved a lot of time.”
Time savings will be a crucial factor in growers' acceptance of the new technology, Lemon says. “We still have a lot of conventional cotton farmers in Texas who have not adopted Roundup Ready technology. But they are considering it. Many don't own hooded sprayers and Roundup Flex offers them an opportunity to add technology without investing in equipment.”
Lemon expects to see significant acreage of Flex cotton varieties planted in 2006. He says farmers are looking for ways to increase efficiency and farming more acreage to spread equipment cost offers one way to do that. Flex varieties and other technology allow farmers to “get across more acres quickly. It also gives them the flexibility to apply Roundup tank mixed with insecticides and plant growth regulators.”
Ray Young, a Louisiana cotton consultant, admits to some concern that Flex technology is “too easy. Farmers may be tempted to use just Roundup. That would be a mistake. We often need a residual herbicide and a clean-up after a third Roundup application.”
He says technology in the seed is in its infancy. “The surface hasn't been scratched. We'll see things within the next few years that will be amazing.”