Jesse Flye wishes he knew six years ago what he knows now: an effective weed control program requires a strategic approach with more than one kind of ammunition.
"I wish someone had told me back then how bad these weeds can be, but maybe I wouldn’t have listened," he says, only half joking.
But Flye is listening now -- and taking action -- to knock out weeds by using a number of control measures, including crop rotation, multiple herbicide modes of action, overlapping products and even chopping weeds, when necessary.
Flye’s mindset is what other farmers need to adopt if they are serious about putting a chokehold on weed problems in 2013, notes Ford Baldwin.
"You need tillage diversity, herbicide trait diversity and crop diversity," advises Baldwin, owner of Practical Weed Consultants LLC and former University of Arkansas Extension weed specialist.
Flye starts each season with a burndown product on every acre of corn and soybeans he grows. Beyond that, he strives to include four to five different active ingredients each year in his corn and soybean weed-control programs.
"We won’t ever go back to using just one herbicide for weed control, even if it’s a silver bullet," says Flye, who farms 12,000 acres of corn, cotton, rice, soybeans and wheat with his dad, Marty White, and brother, Logan White, near Trumann, Ark.
In corn, Flye starts out with a burndown application of Gramoxone (paraquat) in the spring. He then applies Dual (metolachlor) behind the planter to take out annual grasses and small-seeded broadleaf weeds. Once the corn is emerged, he applies a tankmix of atrazine, Roundup and Laudis (tembotrione) for residual control of grass and broadleaf weeds, including herbicide resistant Palmer amaranth.
For soybeans, Flye rotates between the Roundup Ready and LibertyLink systems. Flye prefers the former system because of its lower cost and the yield advantage he sees on his farm. However, he uses the latter system on about 20% of his acreage to control severe Palmer amaranth pressure.
"Some of our rental ground we’ve started farming has a pretty foul seed bank, and I’d be afraid of going with Roundup only," he says.
Baldwin encourages farmers to rotate between Roundup Ready and LibertyLink technologies in soybeans and to work in conventional crops whenever possible.
"If you follow corn with Roundup Ready soybeans one year, then use LibertyLink soybeans the next year after corn," Baldwin advises.
For both the Roundup Ready and LibertyLink systems, Flye’s herbicide program includes a burndown application of Gramoxone mixed with 32% fertilizer and water.
"We have found the fertilizer makes an excellent drift retardant; that is the main reason we include it in our burndown program," Flye says.
He adds that he uses the same technique in corn also.
"With the corn you get the added benefit of getting some of your nitrogen out" on the field, he explains.
In soybeans, right before planting or immediately after, he applies Valor (flumioxazin).
"We like to overlap our preemerge herbicides; we believe that gives us the best control results," he says.
Overlapping herbicides is a good strategy for farmers who are willing to manage the process needed, says Aaron Hager, University of Illinois Extension weed scientist.
Essentially, you need to match the herbicide and application timing to the biology of the weed you particularly need to control. For instance, overlapping herbicides works particularly well on acreage infested with waterhemp because that weed typically flushes multiple times during a single growing season, Hager explains.
The trick is knowing how close together to make the herbicide applications, adds Kevin Bradley, University of Missouri Extension weed specialist
"You want to put a preemergence herbicide on as close to planting as possible, then the second application roughly two to three weeks later postemergence to get grasses and anything that broke through the first application," Bradley explains.
Once Flye’s soybean crop reaches the second trifoliate, he applies either Roundup (glyphosate) or Liberty (glufosinate), depending on which system he’s using in a particular field, in addition to Prefix, a combination of S-metolachlor and fomesafen.
Bradley says the LibertyLink system works well as long as growers understand they need to use full rates, spray weeds under 3" tall and get good coverage.
Flye says his weed control costs across crops have more than doubled, from an average of $30 an acre to $70 an acre in the past six years, yet he believes the results are worth the investment.
"With grain prices what they are today, it’s a good time to use these herbicides, especially the preemerge products," he says. "We feel like they’re a good investment."