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TECHNOLOGY & PLANTS: Glyphosate-resistant weeds are huge challenge to Monsanto’s business



                                  PART 1


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TITLE:   GLYPHOSATE-RESISTANT WEEDS ARE HUGE CHALLENGE

SOURCE:  Wallaces Farmer, USA

AUTHOR:  

URL:     http://wallacesfarmer.com/story.aspx/glyphosateresistant-weeds-are-huge-challenge-51888

DATE:    09.08.2011

SUMMARY: "In early July, members of the Iowa Soybean Association executive board traveled to Tennessee and to the Boot Heel of Missouri to talk to farmers there who are experiencing serious problems trying to manage glyphosate-resistant weeds. The two main weeds those Tennessee and Missouri farmers are challenged with are glyphosate-resistant horseweed (marestail) and Palmer pigweed. Weeds that won?t die, even when sprayed with higher rates of glyphosate, have become an increasingly bigger problem in the southern United States during the past several years."

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GLYPHOSATE-RESISTANT WEEDS ARE HUGE CHALLENGE

In early July, members of the Iowa Soybean Association executive board traveled to Tennessee and to the Boot Heel of Missouri to talk to farmers there who are experiencing serious problems trying to manage glyphosate-resistant weeds. The two main weeds those Tennessee and Missouri farmers are challenged with are glyphosate-resistant horseweed (marestail) and Palmer pigweed. Weeds that won?t die, even when sprayed with higher rates of glyphosate, have become an increasingly bigger problem in the southern United States during the past several years.

The ISA farmers who went on the trip are president Randy VanKooten, president-elect Dean Coleman, secretary Tom Oswald, treasurer Mark Jackson and at-large member Ron Heck. During the same month, farmers in Iowa were reporting incidents of weeds suspected to have evolved resistance to glyphosate.

The ISA leaders who made the trip South met first with Johnny Dodson of Tennessee, who said the problem started about 7 to 8 years ago with marestail. At first, he observed a missed plant (a weed that escaped or survived the herbicide treatment) here and there in the field. Shortly after that, glyphosate resistance was discovered in Palmer pigweed (a pigweed species very similar to waterhemp).

Southern farmers now make multiple passes, spraying multiple products

Dodson, a long-time leader of the American Soybean Association, reported that farmers in his area now make multiple passes, spraying with multiple products. While his fields are very clean, Dodson said his cost of chemicals now runs close to $60 an acre.

>From there, the ISA leaders crossed the Mississippi River and went to the research facility run by the University of Missouri. Weed science professor Jason Weirick showed them dicamba-resistant soybeans and explained how this new technology fits into a herbicide resistant weed management program. While this technology looks very promising, the researchers said there is no silver bullet and farmers will need all modes of action to fight the problem of glyphosate resistance in weeds.

His motto for new weed control strategy is ?start clean, stay clean?

The group looked at plots where Palmer pigweed had choked out both soybeans and corn. Weirick reported that, by the time a weed is 4 inches tall, it is too late to kill it with a chemical. He also said a 4-inch tall weed will have several generations of weeds underneath it that will be shaded from a chemical application. Palmer Amaranth will grow 2 to 6 inches a day. Thus, Weirick?s motto is ?Start clean, stay clean.?

Speaking from experience, the Southern researcher told the ISA group one plant will turn into 10,000 plants, spread by the combine throughout the field, and he pressed the point that the days of post-only applications are over. They talked about weed escapes and how one weed is one too many. In the past, farmers have been told 95% control was good enough, but even one resistant weed cannot be allowed to go to seed.

Southern farmers have had to change the way they apply herbicides

Southern farmers have changed the way they apply their weed control chemicals. They now apply 15 to 20 gallons per acre with a flat fan tip for maximum coverage. They have also developed hooded sprayers that run between the rows, applying gramoxone.

For fields that have got away from them, they?ve hired crews to chop the weeds out at a cost of $20 to $60 an acre. Because even the weeds that were chopped out would still produce a seed head as soon as the cut healed over, some farmers have disked fields down and replanted.

Iowans came back with conclusions on need for new weed strategy

The ISA officers came back to Iowa from their visit down South with some sobering conclusions.

?The take-away message was we need to be proactive and use a residual herbicide product to protect glyphosate-resistant crop technology,? says Heck. ?If you see any weeds after spraying, you need to determine why it wasn?t killed by your chemical application, and what is your plan is to deal with it if it is a glyphosate-resistant genotype. We need to avoid applying glyphosate as a one-pass product applied when the weeds are too large to be effectively controlled.?

Iowa State University Extension weed scientist Mike Owen accompanied the ISA farmer leaders from Iowa. Since the early 1990s, Owen has been warning that farmers must be careful stewards of the glyphosate-resistant crop technology. ISA has funded projects through which Owen will continue surveying Iowa for the evolution of weeds resistant to glyphosate, as well as other herbicides, and working to develop management tactics for herbicide-resistant weed populations.

Iowa farmers need to make changes, diversify their weed managment

?What we saw in Tennessee was similar to what we?re seeing across Iowa,? Owen says. ?Weeds are not being effectively controlled by the management practices farmers are using. Specifically, weeds are not being effectively managed by glyphosate alone. The weed is different, in that Palmer pigweed may be somewhat different from the waterhemp species we have here in Iowa, but the similarities are greater than the differences.?

Owen adds, ?There?s one thing that needs to happen. That is, farmers to need to diversify their weed management program. The way to do that is to use either an early preplant herbicide, which I?d recommend, or a pre-emergence herbicide. The key is that farmers must choose carefully to be sure they have the herbicide that acts on the weeds they?re dealing with and not rely on one product.?

All who were on the trip agreed that being proactive by practicing good management is key. That way, ?a great tool can remain effective for years to come,? says Van Kooten.

ISA will continue to work with ISU to promote glyphosate stewardship. Watch for more details about the ISA officers? recent trip in an article in the October issue of the Iowa Soybean Review. In addition, a fact sheet,?Glyphosate Stewardship: Fix it Before it Breaks!,? which was first distributed in 2009, is available online (www.iasoybeans.com/productionresearch/publications/glyphosate.html).



                                  PART 2

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TITLE:   ON THE FARM WITH TENNESSEE FARMER JOHNNY DODSON

SOURCE:  Monsanto, USA

AUTHOR:  Monsanto Blog, by Janice Person

URL:     http://www.monsantoblog.com/2011/08/11/on-the-farm-with-tennessee-farmer-johnny-dodson/

DATE:    11.08.2011

SUMMARY: "This trip was long overdue. I?ve been lucky enough to talk to Halls, Tennessee farmer Johnny Dodson several times before [...] I meant to do it for years so when someone was headed out on vacation & I heard there was a group going to visit a few places in West Tennessee and the Missouri Bootheel, including Johnny?s farm, I was glad to be the one tapped as a fill-in. [...] I finally got there the week of the Fourth of July."

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ON THE FARM WITH TENNESSEE FARMER JOHNNY DODSON

This trip was long overdue. I?ve been lucky enough to talk to Halls, Tennessee farmer Johnny Dodson several times before ? I vividly remember some Midwestern soybean farmers borrowing a cotton boll to show Johnny he wasn?t the only cotton person in Kansas City for a meeting and other chances to talk with him about how things were going on the farm or his ideas on topics of current interest.

Each time, Johnny said I should visit the farm sometime. I meant to do it for years so when someone was headed out on vacation & I heard there was a group going to visit a few places in West Tennessee and the Missouri Bootheel, including Johnny?s farm, I was glad to be the one tapped as a fill-in. So after years of thinking I should get to Johnny?s farm, I finally got there the week of the Fourth of July. And like every other chance I?ve had to talk to Johnny, I learned a lot. This time I was with soybean farmers from the Midwest. With cotton and soybeans planted on either side of the road and cows on a nearby hillside, we had a chance to visit for a while.

The whole group spent an hour talking with Johnny about his diversified farm (cotton, soybeans, corn and beef cattle). Since I did the full tour one day, the second day I asked Johnny if he?d mind going through some of this on video so it could be shared more broadly. With so much great information, we are going to make this a series of posts on the Dodson Farm. Today, we start the series with background on the farm, listen as Johnny talks about:

Johnny farms with his 26-year-old son John who came home after college to work with a diversified operation growing cotton, corn, soybeans and a few head of beef cattle.

The Dodsons farm has a lot of wildlife in the area including farming across the Obion River from a wildlife and waterfowl refuge. Among the most notable are rising populations of waterfowl, deer and turkeys.

Johnny says the farm?s production practices have continued to improve as the tools available have improved. Farming a lot of highly erodible land, the family does a lot of no-till farming to maintain a year-round ground cover which encourages wildlife too.

Crop protection products are part of the farm?s weed control and insect programs. He said he?s seen advances in technologies and products for decades and appreciates how these advances contribute to the farm long-term.

Water quality continues to improve thanks to no-till farming which is helping reduce erosion of the fine, silt loam soils here.

We hope you enjoy hearing this straight from Johnny and will come back to hear his thoughts on weed management, weed resistance and farmer involvement in organizations.



                                  PART 3

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TITLE:   WHAT?S A FARMER TO DO WHEN WEED RESISTANCE THREATENS THE FARM?

SOURCE:  Monsanto, USA

AUTHOR:  Monsanto Blog, by Janice Person

URL:     http://www.monsantoblog.com/2011/08/12/whats-a-farmer-to-do-when-weed-resistance-threatens-the-farm/

DATE:    12.08.2011

SUMMARY: "?As a farmer, I take pride in the way my fields look. I would like to have a weed-free field. My landlords that I work for, they like to be able to brag on their crop and how good the crop looks,? [Jonny Dodson] says. [...] The challenge with a few glyphosate-resistant weeds is different because the herbicide remains so effective on so many other species.  [...] And still, yet today, even though there are some weeds out there with some tolerance or resistance to it, the efficacy of that particular herbicide is head and shoulders above the options that are available to us.?"

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WHAT?S A FARMER TO DO WHEN WEED RESISTANCE THREATENS THE FARM?

In a previous post, we learned a bit about Johnny Dodson and his Halls, Tennessee farm. In that post, things at the farm may have seemed idyllic. As he talked, the birds chirped and all seemed right with the world. But reality is, Johnny is in the epicenter of weed resistance. Having grown 30 crops (2011 is his thirty-first and he?s working to make it a success), Johnny says he has seen various weed shifts and challenges presented to him.

Johnny says he?s seen discussion of glyphosate-resistant weeds in the media and he certainly realizes resistance is a significant issue on farms in his area. Driving down the highways, it is fairly easy to spot pigweed going to seed in the area. The reality that many are resistant to glyphosate has been something Johnny?s dealt with first-hand for a number of years.

?As a farmer, I take pride in the way my fields look. I would like to have a weed-free field. My landlords that I work for, they like to be able to brag on their crop and how good the crop looks,? he says.

But Johnny thinks people need to understand that being weed-free is more than putting his pride at stake. ?There is an economic issue involved. Maintaining a weed-free field allows you to increase production. The more weeds you have out there, the more competition you have for the sun, the water and the nutrients that are available in the soil.?

Being able to manage resistance issues on his farm, Johnny doesn?t like the terminology some people use ?some people have used the terminology ?superweed.? I don?t agree with that. I truly think we have been and will continue to be able to manage the weed shifts.?

His decades of experience have shown to Johnny that weed species shift and present challenges and leads farmers to consider which tools, including tillage, best address the issue at hand. He says the broad spectrum effectiveness of Roundup agricultural herbicide and the active ingredient glyphosate is what has made it such a great tool.

The challenge with a few glyphosate-resistant weeds is different because the herbicide remains so effective on so many other species. Johnny explains the tool remains a part of his farm?s weed management because it works so well for him saying ?Roundup Ready crops afford producers one of the most beneficial herbicides there is in the marketplace. And still, yet today, even though there are some weeds out there with some tolerance or resistance to it, the efficacy of that particular herbicide is head and shoulders above the options that are available to us.?



                                  PART 4

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TITLE:   GLYPHOSATE-RESISTANT PIGWEED MANAGEMENT HEADLINES FIELD DAY

SOURCE:  Delta Farm Press, USA

AUTHOR:  Fred Miller, University of Arkansas, USA

URL:     http://deltafarmpress.com/management/glyphosate-resistant-pigweed-management-headlines-field-day

DATE:    08.08.2011

SUMMARY: "Three essential points for effective weed control - start with a clean field, overlap residual herbicides and manage the soil seed bank - were the recurring theme during a July 21 field day at the University of Arkansas Division of Agriculture?s Northeast Research and Extension Center. [...] the best bet for reducing glyphosate-resistant pigweed is to keep it from going to seed. Managing the seed bank includes the best management practices possible followed by hand removal of the few remaining escapes if necessary."

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GLYPHOSATE-RESISTANT PIGWEED MANAGEMENT HEADLINES FIELD DAY

Three essential points for effective weed control -- start with a clean field, overlap residual herbicides and manage the soil seed bank -- were the recurring theme during a July 21 field day at the University of Arkansas Division of Agriculture?s Northeast Research and Extension Center.

Tours during the field day focused on division research aimed at managing glyphosate-resistant pigweed in cotton and soybeans, said Fred Bourland, NEREC director.

Division weed scientist Jason Norsworthy said glyphosate-resistant Palmer Amaranth, or pigweed, has spread quickly through the state and can march through a field quickly if it gets a foothold.

At the Arkansas Agricultural Research and Extension Center in Fayetteville, Norsworthy said he put a single glyphosate-resistant pigweed plant in a 3-acre cotton field to see how fast it would spread. The weed was sprayed four times with Roundup. It recovered each time.

?By the third year, the field was full of glyphosate-resistant pigweed,? he said. ?I cut the field at maturity and found only one cotton boll in the entire three acres.?

Ken Smith, a division weed scientist based at the Southeast Research and Extension Center at Monticello, said an effective pre-plant residual herbicide or Gramoxone, a dessicant herbicide used at planting, can help establish a clean field. He added that good tillage to prepare the seedbed would also help.

Norsworthy evaluated 19 residual herbicides to determine which ones gave the best protection against glyphosate-resistant pigweed. ?Valor and Reflex seem to give the longest coverage in a residual herbicide program,? he said. ?In tests here at Keiser it gave us up to four weeks coverage.?

To overlap residual coverage, Norsworthy said, means you have to spray again in three-and-a-half weeks. In addition, field conditions may require new applications. In clay soils like those at NEREC, the soil tends to crack when it dries after a rain or irrigation.

?Pigweed will come up through those cracks,? Norsworthy said. ?And when you cut a furrow to lay poly pipe, the herbicide coverage will be broken at the furrow and you?ll see more pigweed coming up near the poly pipe.?

Another key to controlling the weed, Norsworthy said, is to spray it when it?s small or 3 inches above the ground, not 3 inches above the top of the crop. ?It?s harder to kill when it gets big.?

Smith said the soil seed bank refers to pigweed seed left on the ground after harvest that can sprout new weeds in the spring. He conducted trials of several methods to help reduce the amount of seed left in the field. No practices like burning the residue, rebedding in the fall, catching and removing the combine trash, or fall-applied herbicides eliminated pigweed seed from the seedbank.

Smith and Norsworthy said the best bet for reducing glyphosate-resistant pigweed is to keep it from going to seed. Managing the seed bank includes the best management practices possible followed by hand removal of the few remaining escapes if necessary.

?If you let this stuff go to seed, you?ve got a problem,? Norsworthy said. ?If you let one escape, that?s one too many.?