I found a thread this morning on the independent forum, New Ag Talk, that discusses cotton herbicide plans that these farmers intend to use in 2010's crop.
Significantly, I doubt if this discussion would have taken place 5 years ago, back when Roundup resistance wasn't a known factor and the main question was, "When do you spray Roundup?" Comments cover Alabama, Arkansas, Mississippi, Missouri and Texas.
If you grow cotton and want a quick basis of comparison, here's the thread:
http://talk.newagtalk.com/forums/thread-view.asp?tid=146482&posts=10&start=1
- Owen Taylor
Wednesday, January 27, 2010
Tuesday, January 26, 2010
Will Roundup Face A Bleak Future Due To Resistant Weeds?
That's the scenario painted by Steve Powels, an Australian plant biologist, who spoke at the recent Pan-American Weed Resistance Conference in Miami.
“Glyphosate (active ingredient in Roundup) will be driven to redundancy in the cotton, corn and soybean belt,” said Powles in a report by Forest Laws in Delta Farm Press. “Outside of these areas of the U.S., then glyphosate should continue to be effective because it is not massively used.
“Within the cotton, corn and soybean belt the massive reliance on glyphosate means that it will be driven to redundancy because many of the big driver weeds such as Palmer pigweeds, waterhemp, ragweed and Johnsongrass will be resistant. There may be many weed species still controlled by glyphosate, but glyphosate will fail on the driver weeds and that means overall failure.”
Friday, January 22, 2010
California: dealing with herbicide resistance in almond orchards
In the row-crop business, we tend to think of herbicide resistance as being just a problem in cotton, grains, peanuts and similar crops. But resistance also has become a factor in orchard crops. Here's an overview of the problem in California's Central Valley and recommendations for dealing with it. It comes from David Doll, University of California Cooperative Extension Farm Advisor in Merced County.
As David writes in a late-December posting on his blog, The Almond Doctor, "Since herbicide resistant weeds are becoming more prevalent in the San Joaquin Valley (think Hairy Fleabane, Horseweed/marestail), it is becoming more important for growers to utilize practices that reduce the chance of herbicide resistance."
He also notes: "Glyphosate is one of the most widely used herbicides for this practice, and, until recently, has provided good control."
As David writes in a late-December posting on his blog, The Almond Doctor, "Since herbicide resistant weeds are becoming more prevalent in the San Joaquin Valley (think Hairy Fleabane, Horseweed/marestail), it is becoming more important for growers to utilize practices that reduce the chance of herbicide resistance."
He also notes: "Glyphosate is one of the most widely used herbicides for this practice, and, until recently, has provided good control."
Putting Roundup-resistant Palmer pigweed in perspective
Carl Hobbs, an agronomist with Helena Chemical Co. (based in Ashburn, Georgia) wrote this morning: "I heard an Alabama farmer friend say yesterday, 'If you have glyphosate resistant Palmer (pigweed), you don't have any other problems.'"
The image above, included in a PowerPoint presentation made by Univerisity of Georgia weed scientist Stanley Culpepper, illustrates that point.
- Owen Taylor
Thursday, January 21, 2010
Georgia study: why glyphosate stewardship fails to gain ground
ShareEditor's Note: The following is from a press release received today from Weed Science, a publication of the Weed Science Society of America. The journal publishes articles on the biology, ecology, physiology, or management and control of weeds. It also focuses on herbicides, growth regulators, and related topics. To learn more about the society, please visit: http://www.wssa.net/
In the southeastern United States , weeds that can tolerate or resist the popular herbicide glyphosate are threatening cotton crops. In the article “Loss of Glyphosate Efficacy: A Changing Weed Spectrum in Georgia Cotton,” (Weed Science Volume 58, Issue 1, 73-79)
Theodore M. Webster and Lynn M. Sosnoskie examine how the use of glyphosate-tolerant cotton (GTC)—created through genetic modification—has affected weed control issues since its introduction in 1997.
The article is featured in the January–February 2010 issue of Weed Science, published by the Weed Science Society of America. As farmers plant more acres of GTC, they are seeing a change in the most prevalent weeds, which now include varieties that tolerate or resist glyphosate.
The two most troublesome weeds in Georgia cotton are:
These weeds typically develop in systems without diverse weed control practices. “The management practices necessary for minimizing the development of herbicide resistance have not been widely implemented,” Webster and Sosnoskie write. They see a need for farmers to work toward greater stewardship, which is the sum of the management decisions and practices used to preserve the utility of a crop trait, and try new or varied weed management strategies that often may be more expensive.
“Agricultural practices aimed at delaying or preventing the development of herbicide resistance are not viewed as being economical in the short term and are not readily used by all growers,” they write. “Because herbicide resistance can spread quickly, indiscriminate use of glyphosate may result in a loss of weed susceptibility for all growers, a tragedy of the commons.” Webster and Sosnoskie identify two reasons why growers are not adopting methods that promote glyphosate stewardship:
The authors outline several possible incentives for cotton farmers, including industry initiatives to promote better glyphosate stewardship and voluntary government farm programs.
However, they say it likely will take a combination of incentives and a move toward new methods to improve weed control.
“Principles of ecological weed management used in conjunction with herbicide-based weed control systems will likely be an important component of future weed management systems,” Webster and Sosnoskie write.
They also identify several areas for future research: how to limit the development of herbicide-resistant and herbicide-tolerant weeds; whether there is a need to limit the use of glyphosate; factors that may improve control and stewardship of herbicide options; how herbicide resistance traits move across the landscape; what factors could be used to determine a species’ risk of developing resistance; and incentives to help improve herbicide stewardship. The full-text article is available at http://www2.allenpress.com/pdf/WEES_58.1_73-79.pdf.
Farmers who use herbicide-tolerant crops face a growing challenge from herbicide-tolerant and herbicide-resistant weeds, which are evolving and spreading across cropland.
In the southeastern United States , weeds that can tolerate or resist the popular herbicide glyphosate are threatening cotton crops. In the article “Loss of Glyphosate Efficacy: A Changing Weed Spectrum in Georgia Cotton,” (Weed Science Volume 58, Issue 1, 73-79)
Theodore M. Webster and Lynn M. Sosnoskie examine how the use of glyphosate-tolerant cotton (GTC)—created through genetic modification—has affected weed control issues since its introduction in 1997.
The article is featured in the January–February 2010 issue of Weed Science, published by the Weed Science Society of America. As farmers plant more acres of GTC, they are seeing a change in the most prevalent weeds, which now include varieties that tolerate or resist glyphosate.
The two most troublesome weeds in Georgia cotton are:
- Benghal dayflower, which is tolerant to glyphosate and many of the herbicides used in agronomic crops.
- Palmer amaranth, which has developed resistance to many classes of herbicides including glyphosate.
These weeds typically develop in systems without diverse weed control practices. “The management practices necessary for minimizing the development of herbicide resistance have not been widely implemented,” Webster and Sosnoskie write. They see a need for farmers to work toward greater stewardship, which is the sum of the management decisions and practices used to preserve the utility of a crop trait, and try new or varied weed management strategies that often may be more expensive.
“Agricultural practices aimed at delaying or preventing the development of herbicide resistance are not viewed as being economical in the short term and are not readily used by all growers,” they write. “Because herbicide resistance can spread quickly, indiscriminate use of glyphosate may result in a loss of weed susceptibility for all growers, a tragedy of the commons.” Webster and Sosnoskie identify two reasons why growers are not adopting methods that promote glyphosate stewardship:
- The belief that a new technology will be developed to solve the resistance and tolerance problems, although no new herbicides have been introduced commercially since 1998
- The belief that resistance management strategies will be futile because most farmers think herbicide resistance traits are mobile through pollen-mediated transfer and their fields are affected by other nearby farms
The authors outline several possible incentives for cotton farmers, including industry initiatives to promote better glyphosate stewardship and voluntary government farm programs.
However, they say it likely will take a combination of incentives and a move toward new methods to improve weed control.
“Principles of ecological weed management used in conjunction with herbicide-based weed control systems will likely be an important component of future weed management systems,” Webster and Sosnoskie write.
They also identify several areas for future research: how to limit the development of herbicide-resistant and herbicide-tolerant weeds; whether there is a need to limit the use of glyphosate; factors that may improve control and stewardship of herbicide options; how herbicide resistance traits move across the landscape; what factors could be used to determine a species’ risk of developing resistance; and incentives to help improve herbicide stewardship. The full-text article is available at http://www2.allenpress.com/pdf/WEES_58.1_73-79.pdf.
Tuesday, January 19, 2010
Managing Herbicide Resistant Palmer Amaranth (Pigweed) in Field Corn, Peanut, and Soybean - 2010
Eric P. Prostko, Georgia Extension Weed Specialist, has released a white paper on dealing with glyphosate-, atrazine- and ALS-resistant weeds in that state. He includes a variety of weed control options. including approaches where Roundup/glyphosate and ALS resistance are found in the same field.
Here's a link to the paper.
Here's a link to the paper.
Top 10 Questions And Answers About Liberty-Link Soybeans And The Fit With Roundup Resistance
Two Georgia Extension workers released a white paper this month on where, generally speaking, Liberty-Link (LL) soybeans will fit in that state, especially from the standpoint of dealing with Roundup-resistant pigweed, which probably rates now as that state's number one agronomic problem in field crops.
Nobody is saying that LL beans are a silver bullet, and the report delves into some limitations with the system. But the paper does examine the parameters of the technology. It was written by Jared R. Whitaker (Extension Agronomist – Soybean and Cotton) and Eric P. Prostko (Extension Agronomist – Weed Science).
Here's a link to their report.
Nobody is saying that LL beans are a silver bullet, and the report delves into some limitations with the system. But the paper does examine the parameters of the technology. It was written by Jared R. Whitaker (Extension Agronomist – Soybean and Cotton) and Eric P. Prostko (Extension Agronomist – Weed Science).
Here's a link to their report.
Roundup Flex: Treat it like regular Roundup Ready cotton now?
The Beltwide Cotton Conference, as you might expect, included plenty of data and comments about Roundup Ready cotton, especially the new Flex varieties that allow Roundup applications past the fifth node, the cutoff point for first-generation Roundup Ready varieties.
More than once, I heard Extension workers and even some crop consultants say that it will be far safer to treat Flex cotton the same as the first-gen varieties. Reasons include the need to hit weeds far earlier than cotton's fifth node to gain better control and reduce potential for more Roundup-resistant weed development. With many of the weed sessions focusing on Palmer pigweed -- and secondarily on marestail (horseweed) and things like Italian ryegrass -- resistance management or prevention was on everyone's mind, whether or not they now have the problem.
One estimate given was that Roundup Ready cotton, in general, had lost $19 per acre of its value for growers due to continued reissntance problems. That number was given by a university weed scientist during the consultants conference, which preceeded the Beltwide.
Roger Carter, a veteran crop consultant from east-central Louisiana, wrote in his Beltwide report on January 10:
"One focus was on the economic value of the cost of transgenics. Surveys of farmers and consultants indicated that the current charges for biotechnology, particularly the Flex charges, are much too high in exchange for the good we are getting. Because of resistance management more residual herbicides are needed than ever before. And more direct contact herbicides are necessary to battle resistant pigweeds and other species. Therefore, the use of glyphosate over the top after the 5th true leaf on cotton is a mute point in areas where we are using resistance management programs. And that should be most of the Cotton Belt. Are you listening, folks?"
More than once, I heard Extension workers and even some crop consultants say that it will be far safer to treat Flex cotton the same as the first-gen varieties. Reasons include the need to hit weeds far earlier than cotton's fifth node to gain better control and reduce potential for more Roundup-resistant weed development. With many of the weed sessions focusing on Palmer pigweed -- and secondarily on marestail (horseweed) and things like Italian ryegrass -- resistance management or prevention was on everyone's mind, whether or not they now have the problem.
One estimate given was that Roundup Ready cotton, in general, had lost $19 per acre of its value for growers due to continued reissntance problems. That number was given by a university weed scientist during the consultants conference, which preceeded the Beltwide.
Roger Carter, a veteran crop consultant from east-central Louisiana, wrote in his Beltwide report on January 10:
"One focus was on the economic value of the cost of transgenics. Surveys of farmers and consultants indicated that the current charges for biotechnology, particularly the Flex charges, are much too high in exchange for the good we are getting. Because of resistance management more residual herbicides are needed than ever before. And more direct contact herbicides are necessary to battle resistant pigweeds and other species. Therefore, the use of glyphosate over the top after the 5th true leaf on cotton is a mute point in areas where we are using resistance management programs. And that should be most of the Cotton Belt. Are you listening, folks?"
Organic group contends industry study "echoes" its findings on overuse of glyphosate
The Organic Center (TOC) contends in a press release today that a recent study - that included participation by two Monsanto scientists - "echoes" conclusions that the center's staff already has drawn about the effect that overuse of Roundup is having on the future of transgenic crops.
From the press release:
"Published in Proceedings of National Academy of Sciences (PNAS) in December 2009, the Monsanto-funded research states that 'evolution of resistance to the widely used, nonselective herbicide glyphosate in weedy species endangers the continued success of transgenic glyphosate-resistant crops and the sustainability of glyphosate as the world's most important herbicide.'"
It always seems a bit suspect when organic groups fret over the future of conventional and biotech ag.
From the press release:
"Published in Proceedings of National Academy of Sciences (PNAS) in December 2009, the Monsanto-funded research states that 'evolution of resistance to the widely used, nonselective herbicide glyphosate in weedy species endangers the continued success of transgenic glyphosate-resistant crops and the sustainability of glyphosate as the world's most important herbicide.'"
It always seems a bit suspect when organic groups fret over the future of conventional and biotech ag.
Subscribe to:
Posts (Atom)