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NOTE: Long but interesting article on the decline of GM herbicide-tolerant crop/no-till farming. Worth reading to the end to see that the experts are recommending returning to farming methods that many of us will recognize as agroecological/organic.

EXCERPTS:

"In some states, they've had to move away from no-till because herbicides have been used so exclusively."

As early as 1994, outspoken South Dakota researcher Dwayne Beck said he wrote to Monsanto to warn of the likelihood of resistance developing to its popular product. The company's response was that there was no indication it would happen with proper application. It's no surprise to him now that it's a growing problem.

U.S. farmers now apply 150 million pounds of Roundup to 100 million acres of cropland every year. "It's great technology," Beck said. "But think of Roundup Ready as taking a pill rather than doing your exercise."

Beck, who hails from the Dakota Lakes Research Farm near Pierre, is a blunt spoken South Dakotan. He boils it down to farmers being too easy for weeds and pests to predict. "The bottom line is a human has to be smarter than a bug," he said. "And that's a challenge." Creating new chemicals won't solve the longer-term problem of why and how herbicide resistant weeds develop, he said. And while he's not against technology, he said farmers could benefit by focusing on improved farming methods rather than on new products. "We've been given the idea that weed control is a dead simple solution: just picking the right herbicide," Harker agrees. "It has nothing to do with herbicide, it's all about good agronomics."
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Farmers look to broader strategies to battle weeds
By Candace Krebs
Ag Journal
Posted Mar 11, 2011
http://www.agjournalonline.com/features/x698043326/Farmers-look-to-broader-strategies-to-battle-weeds

Enid, Okla. - Joe Armstrong compares modern weed control strategies to the historic Pony Express which once came through his hometown of St. Joseph, Mo.

ӬAlong each leg of the mail delivery route, the goal was to mount a fresh horse and "ride it as hard as they could," before jumping on the next one.
ӬLikewise, farmers who rely too heavily on popular herbicides eventually exhaust their usefulness and are forced to look for something new. But herbicides are costly and time-consuming to bring to market.

Ӭ"We can be the example for states that have abused herbicide technology," the Oklahoma State University weed specialist said earlier this year, speaking at a conservation tillage meeting in Northwest Oklahoma. "In some states, they've had to move away from no-till because herbicides have been used so exclusively."

ӬAs farmers shift away from tillage and widely adopt Roundup Ready crops tolerant to glyphosate applications, herbicide resistant weeds are gradually emerging and increasing in number. Watching the potency of one of the most popular tools in the last half-century of farming decline is no small matter.

Ӭ"It's a big concern for farmers, because it adds more expense to their weed control programs," said Phil Blandford, of Burlington, Colo., who serves on the Colorado Conservation Tillage Association board of directors.

Marestail, or horseweed, was one of the first weeds to become resistant and is one of the most widespread problems, but Italian ryegrass, palmer amaranth and kochia are others, according to Neil Harker, a weed scientist from Canada who spoke at the No Till on the Plains Annual Conference in late January.

In some cases, Roundup is pre-applied and then applied three or four times to the same field during the growing season, which creates selection pressure, Harker said.

Year after year rotations, like corn and soybeans, are a pathway to problems because they are so repetitive. On the High Plains, a "chem-fallow" practice of leaving ground idle for 24 months to build up soil nitrogen also creates an avenue to weed resistance.ӬӬLife after Roundup Ready
ӬAs early as 1994, outspoken South Dakota researcher Dwayne Beck said he wrote to Monsanto to warn of the likelihood of resistance developing to its popular product. The company's response was that there was no indication it would happen with proper application. It's no surprise to him now that it's a growing problem.

Ӭ"Resistance is a natural thing," said the popular no till speaker who was on the program at the High Plains No Till Conference in Burlington, Colo., earlier this year. "If farmers want to use this technology they need to protect it. It's not Monsanto's problem to protect the technology, it's the farmers' job."

ӬApplying it at reduced rates, at the wrong time or in the wrong way can hinder its effectiveness and give weeds the upper hand, he and other experts say.

ӬWith glyphosate in the toolkit, it's easy for farmers to get lazy. It's the closest thing they have to a magic bullet, killing a broad spectrum of plants safely with little known residual impact on the environment. Glyphosate now accounts for $5.5 billion in sales worldwide, more than all other herbicides combined.

ӬIn addition, the biotechnological development of Roundup resistant crops means farmers can quickly and easily treat entire fields without harming the plants they intend to harvest.

The miracle drug has also become more affordable: costs have come down from around $80 a gallon in the early years of Roundup Ready adoption to as low as $10 today with generic versions.

ӬAs a result, U.S. farmers now apply 150 million pounds of Roundup to 100 million acres of cropland every year.

"It's great technology," Beck said. "But think of Roundup Ready as taking a pill rather than doing your exercise."

Instead of managing their cropping systems for maximum weed control, many farmers simply apply a chemical, Beck contends, just as they would if they had a way to stay fit and keep their weight down by merely popping a pill instead of working out everyday and eating healthier.

Ӭ"Everyone wants to point at the biotech as the issue," Beck said. "It's like the guns: it's not the guns, it's the idiots with the guns. It's the way we use them that matters."

Weed specialists like OSU's Armstrong recommend using a cocktail of pre-emergence herbicides representing different modes of action. Getting a jump on things is important; his studies show weeds begin interfering with yields as soon as 7 days after the crop emerges.

"Because of reduced tillage, you're going to see an increase in winter annual weeds," he said. "Herbicide timing is absolutely crucial in no-till because weeds grow fast, and options for control are quickly lost."

Mixing up modes of action can reduce the speed at which resistance develops. But even that isn't a cure-all. Armstrong points to water hemp in Illinois that developed resistance to its fifth mode of action last summer, a rare example of how savvy weeds can be.

Targeting weeds more precisely might help. Dietrich Kastens, a farmer and well-known ag technology specialist from Herndon, Kan., said precision weed management ”” imagine a direct-injection rig that senses weed pressure as it goes across a field ”” has potential but is still in the very early stages of development. "That's fruit that is way up on the tree," he said. "But it's typical of the farmer mentality to throw more technology at a problem that was created by technology."

ӬIn no till circles at least, experts say farmers need to stop looking for shortcuts and instead become increasingly sophisticated managers of their resources.

Ӭ"Most of us grew up in a world where we looked at each crop by itself," Kastens said. "Now we know we need to be looking at the whole system."

Beck, who hails from the Dakota Lakes Research Farm near Pierre, is a blunt spoken South Dakotan. He boils it down to farmers being too easy for weeds and pests to predict. "The bottom line is a human has to be smarter than a bug," he said. "And that's a challenge." Creating new chemicals won't solve the longer-term problem of why and how herbicide resistant weeds develop, he said. And while he's not against technology, he said farmers could benefit by focusing on improved farming methods rather than on new products.

"We've been given the idea that weed control is a dead simple solution: just picking the right herbicide," Harker agrees. "It has nothing to do with herbicide, it's all about good agronomics."Ӭ

What he wraps into the term "integrated weed management" includes careful seeding, fertilization and disease control to insure a competitive stand and a healthy crop canopy; diversifying not only crops and the timing of herbicide applications but alternating between spring and fall-planted crops; and careful harvesting targeted at preventing weeds and volunteer from sprouting later.

ӬOSU precision nutrient management specialist Brian Arnall is finding in his research that poor soil pH, or acidity levels, can inhibit herbicide longevity, further implicating the health of the entire farm eco-system in effective weed control.
Ӭ"We aren't letting our herbicides live the length they need to live," he said. "That's a recipe for resistance."ӬӬ

To till or not to till
Ӭ
Across portions of the High Plains, tumble windmill grass is emerging as one of few plants that doesn't capitulate to glyphosate. Atrazine-based products are effective on first-year plants, but once they mature, they become resistant even to that.
Ӭ"I think the only thing successful there is very shallow sweep tillage," OSU's Armstrong said.ӬThat brings up the question of whether weed control challenges could drive farmers back to the use of traditional tillage practices.

ӬNorthwest Oklahoma district agronomist Roger Gribble said farmers need not take a doctrinaire approach to eliminating tillage.

Ӭ"Don't let anybody ever define no till for you," he said. "If there's a Bible out there, maybe somebody would subscribe to that. But I don't know of one. There are places in a no-till system where I would use some tillage."

Jimmy Wayne Kinder, an early adopter of no till from Chattanooga, Okla., said the weed issue will force producers into hard choices over whether to till or not to till, with two distinctive paths in front of them.

In his case, he's already past that fork in the road.

"I'm not going back to plowing," he said. "I've had some of my land in no till for 18 years now. I've paid my dues."