Zero Tolerance
February 14, 2012 On a recent trip through the Arkansas Delta, Extension weed scientist Dr. Ken Smith highlighted two fields. One, a soybean field, was so overtaken by Palmer amaranth that onlookers had to strain to find the row crop. The other, a cotton field, was so clean that witnesses suspected that a hoe crew had been through the day before. Pigweed infestation in this corner of the Arkansas Delta was at an all-time high, after all. In any case, it was hard to believe that both fields belonged to the same grower, Pace Hindsley.
Like nearly all growers in his area, Hindsley saw glyphosate-resistant pigweed creep onto most of his acreage over the course of the past few years. But through teaming up with Smith, he implemented a highly effective program.
The idea, according to Smith, was simple: pull out all the stops. At Smith’s direction, Hindsley took a no-holds-barred approach to pigweed. In utilizing every possible weed management tool over the course of the year, Hindsley would reduce the effort and cost of weed management in the following years – knowing full well that front-end costs would skyrocket. The name the duo adopted for the program was an accurate one: Zero Tolerance.
“I kept my Zero Tolerance field clean all year long,” Hindsley says, standing in a pristine field of waist-high cotton. “And we reduced the seed bank by 90% in one year. So there is hope in doing this system. Now it’s a little expensive on the front end, but I spent a ton of money (on glyphosate-resistant weeds) last year without this program. With Zero Tolerance, it’ll pay dividends as we move forward.”
The program was extensive. Starting in February, Hindsley used a pint-and-a-half per acre of Roundup, accompanied by a pint-and-a-half of gramoxone. After that, he came back and incorporated Treflan at a pint-and-a-half per acre. He then used bedder rollers to create flat, firm seed bed, and put out a pint of Reflex. Hindsley says that application lasted four to five weeks, and gave him enough time to plant, at which time he broadcast a pint-and-a-half of Cotoran behind his planters.
“To keep this zero tolerance approach, you’ve got to seriously overlap these chemicals. You can’t let one play out, because once you let one play out and the pigweeds come, you’re almost fighting a losing battle,” Hindsley says.
After the Cotoran application, Hindsley utilized 2.3 pints of Warrant and a pint-and-a-half of Roundup over the top of his cotton. After 21 days, he applied 2.5 pints of Sequence over the top.
Hindsley then utilized what he calls the “best money I spent all year” – his Willmar 915 hooded sprayers.
“They’re the old-style hoods. They’ve got the apron in the front and the apron in the back. They’ve kind of beefed up in the front, and it has these bars that will actually drag these pigweeds through these hoods. And I’ve had some large pigweeds come through that hood, and the Gramoxone – I’ve used 40 ounces of Gramoxone – and a quart of Prefix, knocked it out. It did a great job,” Hindsley says.
He also used the hoods to apply his “old standby” of MSMA at a pint-and-a-half and diuron at a half pint. Hindsley says he’s counting on that application to last him through the rest of the season.
“The cotton is lapping now, so it shades the middles out. I should be clean through harvest,” he says.
Winning the War on Seed
The program has already paid dividends in Hindsley’s fields. Since last year, Smith says he has reduced the Palmer amaranth seed bank by 90%. The weed scientist has made that term – seed bank – a major talking point when speaking with Arkansas growers over recent years.
“If there is an Achilles heel for this pigweed, it is that the seed do not live long-term in the soil. If we take pigweed seed and put them in a greenhouse, when the temperature gets right, they almost all immediately germinate. So there’s not a long dormancy in pigweed seed, and that’s good. We’re trying to capitalize on that weakness,” Smith says.
“Now, it overcomes that weakness with sheer numbers. There’s no other pigweed that produces anything even close to what the Palmer will in terms of numbers of seed. That’s its survival mechanism is to just overpopulate with more and more seed. So if we can learn to manage that, then I think we’ll have a tool that we can combine with all these other tools to get pigweed back down to a manageable level.”
Smith says that was the concept when he first approached Hindsley about trying the Zero Tolerance program in his fields. Because of the experimental nature of the project, Smith couldn’t make any promises when he asked Hindsley to make the significant financial and labor intensive commitment to the Zero Tolerance program. Fortunately for both men, the program has been as successful as expected.
“We basically do everything we can do to manage, or reduce the number of pigweed. A lot of time when we talk about Zero Tolerance, the thing that gets highlighted is the hand removal of the weeds. Well, that’s just that last step,” Smith says.
“Even if our herbicide program gets 99.9% of the problem, that may not be good enough if we’ve got a million plants out there. So those few remaining, the ones we take out by hand, that gets all the attention, but in reality that’s only one part of this program that is about reducing numbers. Going in by hand and taking out those very last few – quite frankly that’s very economical,” Smith says.
Chopping Weeds, Cutting Costs
Hindsley agrees. While the program has been costly in its first year, the grower keeps those expenses in perspective.
“It is a lot of money. But compared to last year, my chopping expense on a 65 acre field was 110 hours. This year it is less than 5 hours. So, I hate running a hoe crew more than anyone, but it’s reducing that whole deal. Next year or the next, I could reduce some of these chemicals, so it won’t be as expensive on the back end,” Hindsley says.
The savvy grower is also aware of cost-sharing programs from companies such as Monsanto’s Roundup Ready Performance Plus program, which offers rebates to growers who use select herbicides. And there is even discussion of financial help in combatting this problem from the U.S. government.
In July of 2010, Smith hosted a crew of USDA representatives in Arkansas to examine firsthand the havoc glyphosate-resistant pigweeds were reeking in the state. The idea was to emphasize the importance of a system like Zero Tolerance.
“You know, without this program we may not be able to grow cotton here. So thanks to Dr. Smith, we’ll hopefully get some help in covering these costs to run this system,” Hindsley says. “I don’t know what kind of prices they’re going to provide to help with this, but at this point, any help is appreciated.”
So far this year, Hindsley estimates that he’s spent over $75 an acre on the Zero Tolerance program. While at first glance that number seems staggering, the grower insists that it isn’t a far stretch from the prices he and his neighbors have paid in the past on less effective weed-management systems. Smith agrees.
“Those costs are probably coming back down to that $50 range in the next years of this program. And I know that’s more than we spent when we were only spraying Roundup, Roundup, Roundup. But those days are over. That’s not an option now,” Smith says.
The weed scientist believes programs like Zero Tolerance will go a long way in helping rid Arkansas of the glyphosate-resistance problem.
“I’m not naïve enough to believe that every grower in Arkansas is going to be able to go Zero Tolerance on all his acres. It’s not going to happen. But I want that mindset of managing the seed bank and reducing the numbers. If we can get in that mindset, then it’s easier for us to justify cleaning the turn rows. It’s easier for us to justify going out there and cleaning out those last few weeds,” Smith says.
GET THE NEWSLETTER TODAY!
