|
|
SPECIAL
REPORT
02/23/07
Crop News Weekly
As February speeds to a close and March slips into the
foreground of our farming schedules, it's time to offer up the latest in
our ongoing special reports about weed resistance. Last month we
presented the latest information about glyphosate weed resistance in
corn crops. In this issue we continue to lay the groundwork for the
latest research, trends, and general information about this evolving and
troubling problem in American agriculture. At stake is the issue of what
to do when weeds in the field resist tried and true management
techniques and herbicide applications and begin to cut into yield,
production and profit on the farm. Pointing the finger and placing the
blame on who and what is the source of the evolving dilemma doesn't
solve the issue. Growers are looking for straight forward and practical
answers to the problem and we're dedicated to at least trying to provide
adequate and relevent alternatives if not all the right answers. For
those of you with existing and serious glyphosate resistant weeds in
your fields, the challenges are very real and there is a sense of
urgency in your need for answers. For the thousands who will begin to
see the problem creep into their fields in the months and years ahead,
we hope to provide enough technical resources and information to help
you minimize the negative impact and to help you alter management
efforts to properly adjust to the developping crisis. Keep in mind the
issue continues to evolve, meaning what seems to work today may be
replaced with new methods, theories and new products tomorrow. There may
not be one simple answer, and what we thought to be true and correct
yersterday could easily be outdated next week, next month or next
year.
This is the primary reason we are presenting this special report series
on glyphosate resistance, what we hope will be a useful and informative
tool to help you stay on top of the latest developments on the issue. As
always, we are open to and encourage your comments and feedback. While
we diligently scour through research papers and reports, white papers,
university blogs and industry reports, we firmly believe the best
information often comes from farmers in the field who, with hands-on
experience, often know what does and doesn't work best. Let us hear from
you through the email link at the bottom of this newsletter. Your
experiences and opinions count! - Logan Hawkes
|
ADVERTISEMENT
 Want to shift your glyphosate program into overdrive?
Click here to find out how DuPont™ Resolve™ DF herbicide can rev
up your weed management. www.resolve.dupont.com
|
|
Sharing In The
Blame
Technology on the farm is a wonderful thing. Down
through the years it has saved us money, increased production and,
overall, has made life better for us. The drawback is that while it
often solves many of our problems, it has been known to develop a few as
well. Such is the case with Roundup Ready crops. Roundup Ready crops,
marketed by Monsanto (MON), have been bio-engineered to resist the
herbicide glyphosate, which has allowed farmers to use the chemical to
kill weeds without harming the crop. But now that glyphosate resistance
weeds are becoming more widespread in fields across America, there are
many who are faulting the technology as the sole source of the problem.
However, research on the resistance problem tends to disagree with that
conclusion.
According to Monsanto, in 2005, Roundup Ready crops were grown on more
than 100 million U.S. acres, which include soybeans, canola, corn and
cotton crops. Weed resistance develops when producers widely use a
herbicide with a single site of action, such as glyphosate, repeatedly.
A couple of reasons weeds are becoming resistant to glyphosate are that
farmers are not all applying the weed-killer at recommended rates or are
waiting too long before application to high-density, large weeds.
Farmers also need to begin with clean fields in the spring and eliminate
even small weeds that may be present. And at the risk of losing soil
moisture, early weed resistance problems may call for better tilling
prior to and subsequent to spring planting.
In short, technology on the farm reminds me of an incident from my
youth. Power windows had just come out on U.S. automobiles and I
remember well my father lauding the new technology. For several years
running he couldn't stop admiring the way the new technology had made
rolling the windows up and down on the old Oldsmobile a more efficient
process. That is until the darn thing failed to work one day and the
repair shop had to remove the door panels to get to the root of it.
On the farm we have, perhaps, become complacent about Roundup Ready
technology. Comprehensive tilling of the fields, fewer herbicide
applications and products, and hands-on weeding have all but become a
thing of the past. But when the windows fail to roll down with the push
of a button, then it's time to evaluate the way we do things. When weed
resistance becomes a problem in the field, we need to look hard at ways
to adjust to the problems rather than wasting time on who or what is at
fault. While the technology made our lives better for a while, making
adjustments to new developments is a big part of any game. Perhaps
looking hard at a return to the basics is an appropriate response to the
immediate problem. Alternating or adding other herbicides in your
management practices, resisting excessive glyphosate treatments,
increased tillage and weed removal, these are some of the basics we may
need to consider in order to address an evolving problem in the
industry.
|
Resistance
Demographics
Unlike Asian Soybean Rust and most plant diseases,
glyphosate resistance doesn't necessarily follow a pre-destined path
from field to field. There have been reports of growing resistant weeds,
like Palmer amaranth, or pig weed, from the east coast to the west and
all points in between. But in recent weeks there has been a higher
density of problem areas reported in Southern states.
In Moultrie, Georgia, in Colquitt County, officials are reporting the
region now has full-blown ALS, or acetolactate sythase resistant
pigweed. University of Georgia Extension Agent Scott Brown reports last
year about 80 percent of county fields demonstrated resistance to
treatment. That's compared to 40 percent the year prior and just 20
percent in 2004. He speculates that this year, ALS-resistant pigweed is
predicted to escalate to 90 percent. Five or six Georgia counties have
Roundup-resistance, and more counties are expected. Farmers are losing
the cheapest effective method to control pigweed, glyphosate, because of
resistance. What isn't confirmed in Colquitt County yet is
glyphosate-resistant pigweed. But the problem is close enough that weed
experts from the University of Georgia are warning local farmers to be
vigilant in the fight to keep it at bay.
While there have been ample reports of resistant weeds in Virginia, the
Carolinas, Florida, Alabama and Tennessee, the problems continue to grow
in other regions. Researchers at Purdue and Ohio State universities have
confirmed glyphosate-resistant giant ragweed populations in Indiana and
Ohio. The weed species is the seventh in the United States to show
resistance to glyphosate. Ohio State University Extension weed
scientists are urging farmers to alter their weed control strategies in
2007 to slow the development of glyphosate-resistant weed populations.
They recommend starting with a weed-free cropfield at planting and using
a program of pre-emergence herbicides, followed by a series of timely
postemergence herbicide treatments.
|
ADVERTISEMENT
Rev up weed management with DuPont™ Resolve™ DF
herbicide. It combines a more complete contact control of many
troublesome weeds with residual activity. Resolve™ DF also provides
an additional mode of action to help minimize the occurrence of
resistant weeds in a glyphosate-resistent corn program. See your DuPont
retailer and leave weeds in the dust.
|
|
Determining
Resistance in Weeds
The University of Delaware is reporting
glyphosate-resistant horseweed, or marestail, continues in at least
three counties in Delaware and reports of additional fields infested
with glyphosate-resistant horseweed are coming out of Delaware, Maryland
and New Jersey.
To determine whether weeds in your field are glyphosate resistant,
scientists are suggesting you eliminate other causes of herbicide
failure first. Was the herbicide applied as recommended? Did the plants
emerge after application? Are there patterns to where weeds were not
controlled in the field?
Resistance develops by selecting resistant-biotypes through repeated use
of the same herbicide mode of action. Some questions regarding herbicide
use need to be considered:
Has the same herbicide (or herbicides) with the same mode of action
been used consistently over a period of years?
Has the species been controlled by the herbicide(s) in the recent
past?
Has there been a decline in control with the suspected species?
One of the classic signs for resistance (for all situations where
resistance is to a post-emergence herbicide) is that only one weed
species is present, all others are effectively controlled. If you
suspect resistance, but are still uncertain or your situation is not
covered by the the circumstances above, there is a test you can do
yourself. Mix up a small hand sprayer with 1 % solution of Roundup,
Touchdown, or GlyphoMax (2.5 tablespoons per 1 gallon of water or
one-half cup per 3 gallons of water) and spray the suspected plants. Be
sure to check if a non-ionic surfactant is required with the form of
glyphosate you are using (if needed 2.5 tablespoons per 1 gallon of
water or one-half cup per 3 gallons of water). Spray approximately 30
plants in a small area. Do not "douse" the plants with the spray
mixture, rather a light spray is adequate. Then spray the rest of the
field with the appropriate herbicide to prevent the horseweed from
producing seed. This procedure will help you determine if
glyphosate-resistant horseweed is present in your field, which in turn
will allow better management decisions to be made. Once a field is
identified with glyphosate--resistant horseweed, glyphosate will no
longer control this species and additional management will be needed for
the present year and many future years.
|
Herbicide-Resistant
Weeds Force Change In Agriculture
According to a report from Dow Jones and published on
cattlenetwork.com, U.S. agriculture is changing as a result of
glyphosate resistance. In 2005, Roundup Ready crops were grown on more
than 100 million U.S. acres, which include soybeans, canola, corn and
cotton. With increased glyphosate resistance, the success of Roundup
Ready seeds as a way to reduce weed management problems could be in
question. Scientists and industry experts say producers need to be more
creative weed-killers and can no longer depend on the revolutionary
one-pass-through-the-field approach they have used in the last eight to
10 years with the advent of Roundup Ready.
|
Farmers
can still find life in glyphosate
02/21/07
You might not be able to tell it from all the media
reports these days, but there's still some life left in glyphosate, the
active ingredient in the herbicides used to control weeds in Roundup
Ready systems. Compared to other herbicide modes of action, the number
of documented cases of resistance to glyphosate -- 20 -- is still
low, says Alan York, professor of weed science at North Carolina State
University. The incidence of ACCase- and ALS-inhibitor resistance is
much higher. - Delta Farm Press
|
Resistance
issues remain in Tennessee, Missouri
02/21/07
In 2002, glyphosate-resistant marestail was found
sparsely distributed in the Missouri Bootheel. The next year, Andy
Kendig was finding it "almost everywhere, just driving up and down the
road. And since then it's only gotten worse. "I'm operating under the
premise that, at least for the Delta region of southeast Missouri,
resistant marestail is well-established," says the Missouri Extension
weed scientist stationed at the Delta Center in Portageville, Mo.
"Growers should just assume they've got it." Producers in Tennessee
should assume the same. - Delta Farm Press
|
Glyphosate-resistant
weeds burden pocketbooks
02/21/07
Cotton producers who encounter glyphosate-resistant
horseweed in their fields may be tempted to fall back on a solution that
served their fathers and grandfathers well: cold steel. Before you pull
that disk out of the weeds on the back side of the equipment lot,
however, think about this: Do you really want to spend all that extra
money on diesel fuel and labor and undo the benefits of conservation
tillage you've worked so hard on all these years? - Delta Farm
Press
|
In
Summary
As the evolving weed resistance problem grows across
fields in America we'll continue to do our best to keep you up-to-date
with the latest in news, information and trends that will effect the way
you farm in the months and years ahead. While there may not be a miracle
solution on the near horizon, there are developing methods to fight weed
resistance. Farmers, like the ugly cockroach, tend to adapt well to
their changing environment. And like warriors, they generally rise to
the occasion. Review your weed management program, watch your fields
closely and stay tuned for another update coming in the weeks ahead.
- Logan Hawkes
|
|
ABOUT THIS NEWSLETTER
You are subscribed to this newsletter as #email#
To get this newsletter in a different format (Text or HTML),
or to change your e-mail address, please visit your profile
page to change your delivery preferences.
For questions concerning delivery of this newsletter, please contact our
Customer Service Department at:
Customer Service Department
Corn & Soybean Digest and Farm Industry News
A Prism Business Media publication
US Toll Free: 866-505-7173
International: 847-763-9504
Email:cropnewsweekly@pbinews.com
US Toll Free: (866) 505-7173
International: (402) 505-7173
Prism Business Media
9800 Metcalf Avenue
Overland Park, KS 66212
Copyright 2006, Prism Business Media. All rights reserved. This article
is protected by United States copyright and other intellectual property
laws and may not be reproduced, rewritten, distributed, re-disseminated,
transmitted,
displayed, published or broadcast, directly or indirectly, in any medium
without the prior written permission of Prism Business Media.
About This Newsletter
To unsubscribe from this newsletter go to: Unsubscribe
To subscribe to this newsletter, go to: Subscribe
For information on advertising in Crop News Weekly, please contact: Mike Santi.
|
|
|
|
Farm Industry News
Product
of the Week
View and read about the Farm Industry News Product of the
Week.
Click here to visit farmindustrynews.com
Corn & Soybean Digest
Market News
Richard A. Brock
Check out the latest corn and soybean market advice from
marketing guru Richard Brock by visiting cornandsoybeandigest.com
|
|
