Combating A New Generation Of Weeds

Traditional weed management practices are under attack as glyphosate-resistant Palmer amaranth takes a firm and frightening grip on fields throughout the Mid-south. Yet Southern growers aren’t the only ones concerned, as the now all too common sight of fields overrun with pigweed could spread throughout the Midwest, with the nuisance having already reared its head in parts of downstate Illinois and Indiana and southern Ohio.

While these yield-robbing weeds have traditionally been defeated with basic herbicides, now many growers are finding themselves “out of bullets” as the overuse of glyphosate and other technologies has further elevated the crisis of weed resistance in the U.S.

And, as former University of Arkansas weed science professor Dr. Ford D. Baldwin tells it, ag retailers are in a unique position to alleviate some of these pressures.

“I think this is really a huge opportunity for retailers, and I know retailers get pulled a lot of different ways with incentives from different companies,” he said. “One of the keys in surviving this thing is the companies with the new technologies being able to work together, but I don’t think that’s going to happen anytime soon.

“If retailers keep the growers best interest at heart,” he adds, “then I believe they can in a way force the integration of all of these new technologies without the individual companies ripping each other apart.”

Bayer CropScience, one of those companies Baldwin is referring to, is among those taking the initiative to educate growers and retailers alike on this evolving threat, and CropLife® magazine recently joined the company’s Respect The Rotation tour in Collinsville, IL, to glean valuable new information in this ongoing saga.

Revisiting Residuals

Until recently, Palmer amaranth was in many ways no different from any other run-of-the-mill weed. It is the widespread development of glyphosate-resistance in the species that has catapulted pigweed into a dubious category Baldwin refers to as “Driver Weeds,” or as he explains it “weeds that if you don’t control them, nothing else matters.”

So, in the era of glyphosate-resistance, how does one control pigweed? In the past, a correct answer to that question would be the addition of residual herbicides to the cropping plan. Not now, however.

“My message to growers is simple: don’t just use residuals, you’ve got to use multiple residuals,” said Baldwin. “You’ve got to get some diversity into your post-emergence applications, so we can save Roundup.”

The reasoning behind advocating increased residual applications is simple: herbicides in the soil can more efficiently kill the weed before germination.

“Why are residual herbicides the number one option for resistance management today?” asks Jason Norsworthy, associate professor of weed science, University of Arkansas. “It’s because they help us with our application timing, and the more you control the weeds never coming up, never germinating and never emerging, the less chance you have for resistance.”

“Also, the residuals reduce the amount of plants that you’re spraying post-herbicides on where you know you have significant, multiple resistance issues,” Norsworthy adds. “On top of that, it expands your application window so you’re spraying smaller weeds, which helps get better spray coverage too, so it is key.”

Another solid management practice that has yet to catch on, but likely will according to Norsworthy, is the overlapping of residual herbicides. “It’s not common yet but it’s starting to increase in terms of our education as well as some companies promoting it a little bit more. It always helps when a company has a particular product to offer in that overlapping of residuals, so it’s becoming a little more common and it’s definitely a direction that I think we need to go.”

With zero new herbicide technologies on the horizon, the industry must respond rapidly before resistance becomes unmanageable.

“The last new herbicide mode of action, or how the herbicide kills the plant, was discovered 30 years ago, so there’s no magic bullet coming down the pipeline,” Baldwin adds. “This is not just a farmer problem anymore. It’s an industry problem.”

A Numbers Game

With Roundup no longer effective on resistant pigweed, the days of cheap and easy weed control are long gone. As many Southern growers have no doubt learned the hard way, after infection the problem becomes so expensive and taxing that experts advise even if current pigweed populations are extremely sparse or non-existent in your area, it takes little effort for it to set up shop permanently. Being proactive, or tackling the problem before it actually becomes a problem, is a must.

“Palmer amaranth is a desert plant that just overpowers you with numbers, and it doesn’t need much water” says Norsworthy. “If you’ve got that ‘just one more year’ mentality, you’ve already lost the war. As a grower, you have to be proactive.”

Norsworthy witnessed first-hand pigweed’s prolific ability to spread. When he began his field work at the University of Arkansas back in 2007, the soybean test plot he was working on had zero pigweed plants. In 2008, same thing. Not a single plant. Then in 2009, a graduate student happened upon three pigweed plants, but Norsworthy thought little of it.

Come the very next year, and the field was, in his own words, “inundated with pigweed.” In 2011, that same field was deemed “unmanageable” by the university. All it took was five years for Palmer amaranth to completely annihilate a soybean field.

Prescribing A Regimen

Although the prognosis going forward seems dim, there are still many tools available. According to Bayer, the top choice currently among many Southern growers is the Bayer LibertyLink system for corn, cotton and soybeans. Dr. Baldwin informally estimates that over 50% of the cotton and 30% of the soybeans planted south of the Mason-Dixon line are utilizing the technology.

“LibertyLink works great, and that’s all well and good, but some of these growers you ask what their plan is for next season and they say LibertyLink, LibertyLink and LibertyLink, followed by more LibertyLink,” laments Baldwin. “But that’s not going to work, and if we do that we’re going to break Liberty quicker than we broke Roundup.”

Instead, Bayer is advocating its Respect The Rotation approach: Rotation of multiple modes of action, yearly rotation of crops and rotation of herbicide-tolerant traits. Residual applications, both pre-and post-planting, the overlapping and overlaying of multiple residuals throughout the offseason and a minimum of three modes of action combined with LibertyLink are also crucial pieces to the puzzle.

Aside from Liberty, some other management options include the family of HPPD traits and the Dow AgroSciences’ Enlist trait in corn and soybeans, and the coming dicamba and 2,4-D formulations that await EPA registration for 2013. Looking even further up the road, BioDirect, a new technology discovered by Monsanto that “uses molecules found in nature that are, like RNA, applied to diminish the production of specific proteins in the target organism,” is showing promise but is reportedly a ways down the pipeline and tentatively set for a 2014 market release.

With once-effective herbicide technologies being lost one-by-one at such a rapid rate (ALS, glyphosate, atrazine, etc.) and the number of herbicide-resistant weeds exploding from zero back in 1950 to 388 species today, agriculture’s ability to outsmart herbicide-resistance is going to make or break our global food production system going forward.

Topics: , ,

Leave a Reply

One comment on “Combating A New Generation Of Weeds

  1. OPINION: So sad that educated persons continue to endorse an agricultural practice (drenching fields in herbicide before planting) that threatens the health of consumers, decreasess the nutritive value of the food and poisons the planet.(not to mention the monopoly created over food held by glyphosate producers) To fatten their bottom line, American farmers continue to embrace the deceptive practice of “no til” (herbicide) farming. Their produce may as well be cardboard…looks great but herbicide is poison! The USDA is at fault for endorsing this practice and rumor has it they get some sort of royalty or kickback for continuing to support this and other questionable “experiments” forced on the unwitting comsumer. Wake up Dr. Ford Baldwin! you are endorsing practices that endanger the health of the planet (I bet he eats organic) Farmers PLEASE consider more sustainable, health enhancing, methods of production.

Herbicides Stories

Soybean Field
HerbicidesOnly ENLIST Technology Provides Tolerance To Three Key Herbicides in Soybeans
July 13, 2016
The herbicide applications have been made, and growers are busy scouting their soybean and cotton fields to see if weeds Read More
Palmer pigweed in soybean stubble
Crop InputsScientists: Herbicide Resistance Predates GMO Technologies By 40 Years
July 12, 2016
You may think weeds resistant to herbicides are a new phenomenon linked to the overuse of glyphosate in genetically engineered Read More
HerbicidesMonsanto, DuPont Form Dicamba Supply Agreement
July 7, 2016
Monsanto Co. and DuPont have announced a multi-year dicamba supply agreement for the U.S. and Canada. Terms of the agreement Read More
Soybean Plant closeup
Crop InputsDow Launching New Soybean Burndown Herbicide
June 30, 2016
With the 2016 growing season nearing the halfway mark, many growers are scouting soybean fields to find unwelcome marestail plants Read More
Trending Articles
Heritage Cooperative
Retail FacilitiesKahler Automation Designs State-Of-The-Art Facility For Heritage Cooperative
July 4, 2016
Heritage Cooperative in Marysville, OH, needed an efficient liquid, dry and grain facility to serve the many needs of their Read More
The Andersons Waterloo
ManagementFirst Indiana Facility Certified Under 4R Nutrient Stewardship Certification Program
June 27, 2016
The 4R Nutrient Stewardship Certification Program has announced that The Andersons, Inc.’s Waterloo, IN, facility has been added to its Read More
Food IT
Industry NewsCalifornia Event Will Mix Ag And Tech Professionals To Explore IT Solutions
June 20, 2016
Silicon Valley is hot on agriculture, and an upcoming event in California will bring together the food and tech industries Read More
Monsanto Luling Plant
Eric SfiligojWhat’s Next For Monsanto?
May 31, 2016
For the folks at Monsanto’s headquarters in St. Louis, MO, it has been an eventful few weeks. Back on May Read More
Soybean Plant closeup
Industry NewsMonsanto Rejects Bayer Bid; Open To More Talks
May 25, 2016
Monsanto Co, the world’s largest seed company, turned down Bayer AG’s $62 billion acquisition bid as “incomplete and financially inadequate” Read More
Eric SfiligojPity The Monsanto Haters
May 23, 2016
An old saying goes thus: “Be careful what you wish for. You just might get it.” Given current events, there Read More
Latest News
ManagementGROWMARK Meeting Visit, Company Takeover Updates, and R…
July 22, 2016
Editors Paul Schrimpf and Eric Sfiligoj discuss their recent speaking engagement at GROWMARK’s eastern event, crop protection company merger rumors, Read More
Crop InputsMonsanto: EU Approves Roundup Ready 2 Xtend Imports
July 22, 2016
Monsanto Co. announced today that the European Commission has granted import approval for Roundup Ready 2 Xtend soybeans. This milestone Read More
Syngenta headquarters in Basel, Switzerland
Crop InputsSyngenta Announces Alfalfa Seed Split Off
July 22, 2016
On September 1, 2016, Syngenta will transfer sales and distribution of alfalfa seed to the NEXGROW branded business that is Read More
Dow DuPont
Crop InputsDuPont, Dow Shareholders Approve Merger
July 21, 2016
DuPont and The Dow Chemical Company announced that, at their respective special meetings of stockholders held today, stockholders of both Read More
ManagementLand O’Lakes Announces SUSTAIN Business Unit, Oth…
July 20, 2016
Land O’Lakes, Inc. today announced the formal organization of a new business unit, SUSTAIN, and its leadership. SUSTAIN will focus Read More
Monsanto Luling Plant
Crop InputsReport: Bayer Shareholder Proposes Monsanto ‘Host…
July 20, 2016
One of Bayer AG’s top 20 shareholders said Wednesday it may make sense for the life-science company to launch an Read More
Young Corn Closeup
Industry NewsNew Leaf Symbiotics Snags Former Monsanto Microbials Le…
July 20, 2016
NewLeaf Symbiotics, announced today the appointment of Dr. Janne Kerovuo as Vice President for Research and Discovery.  Dr. Kerovuo comes Read More
Corn and ditch
ManagementStudy: Saturated Buffers Reduce Nitrates From Subsurfac…
July 19, 2016
The Agricultural Drainage Management Coalition (ADMC), Agricultural Drainage Management Systems Task Force and Dr. Dan Jaynes with the National Laboratory Read More
Case sprayer nozzle closeup
EquipmentAgronomists, CCAs, Custom Applicators Invited To FSR Ag…
July 19, 2016
Agronomists, Certified Crop Advisers (CCA) and custom applicators can stay current on agronomy issues on the grounds of the Farm Read More
Soybean Field
LegislationOhio Soybean Association Names Brian Hill Legislator Of…
July 19, 2016
The Ohio Soybean Association (OSA) has announced that State Representative Brian Hill (R-Zanesville) has been named one of two Legislators of Read More
Eric SfiligojThe Latest Monsanto Rumors: A Game Of Tones
July 18, 2016
When companies are engaged in the back-and-forth of the acquisition game, the tone of their various announcements is always important. Read More
Nozzle spray close-up
AdjuvantsWest Central Distribution Introduces New Elite Family O…
July 14, 2016
West Central Distribution recently released a new line of Elite adjuvants to work alongside the new herbicide technologies that combat Read More
Bayer sign
Crop InputsBayer Makes New Offer For Monsanto
July 14, 2016
Bayer AG boosted its takeover offer for Monsanto Co. to about $65 billion in a bid to overcome the U.S. Read More
ManagementAn Update on Water
July 14, 2016
CropLife Editors Eric Sfiligoj and Matthew Grassi discuss agricultural water issues in conjunction with a recent field trip in Ohio. Read More
Co-Alliance employee
EmployeesNew Purdue Program To Focus On Talent Management
July 14, 2016
Purdue University’s Center for Food and Agricultural Business is starting a new professional development program to help food and agribusiness Read More
Industry NewsFMC Agricultural Solutions Appoints New Global Regulato…
July 14, 2016
FMC Corp. has named Andy Hedgecock as Global Regulatory Affairs Director for FMC Agricultural Solutions. He joins the company this Read More
Corn Field
Seed/BiotechWhat Can Inoculants Do For You?
July 13, 2016
When it comes to preventing disease and promoting growth in your plants, who couldn’t use a helping hand? By forming Read More
Microbes
Seed/BiotechMighty Farming Microbes: Companies Harness Bacteria To …
July 13, 2016
What if farmers, instead of picking up some agricultural chemicals at their local dealer, picked up a load of agricultural Read More