The Resistant Weeds Epidemic

As resistant weeds become more common in crop fields across the country, the entire agricultural community is scrambling to keep pace.

As a long-time independent ag retailer in St. Marys, KS, Doyle Pearl of J.B. Pearl Sales & Service Inc. has grown used to some interesting sights in his grower-customer fields. However, on a recent visit to one customer’s farm, Pearl at first thought he had somehow ended up on a holiday-oriented operation instead of one devoted crops.

“When I looked into the field, I at first thought this grower was harvesting Christmas trees,” says Pearl. “But when I looked closer, I saw these large, bushy plants weren’t pine trees, but weeds. It was then I realized that herbicide-resistant Palmer amaranth had arrived in our area.”

Unfortunately, Pearl is not alone in witnessing this kind of sight. Since the first herbicide-resistant marestail was discovered in Delaware in 2000, the number of similar hard-to-control weeds has rapidly spread across the U.S. At last count, say experts, there were some 14 species of weeds showing single or multiple forms of herbicide resistance in more than 30 states affecting thousands of acres of cropland.

“Palmer amaranth is a huge problem for growers because we’ve seen some plants that have had three applications of Roundup Ready WeatherMax and survived,” says Dwight Lingenfelter, a weed scientist in the department of plant science at Penn State University.

“Waterhemp is another weed that has shown resistance to multiple forms of herbicides and modes of action. There’s even one population of waterhemp that was recently discovered in Iowa that is showing some resistance to 2,4-D.”

Even worse, say industry observers, the cost of dealing with these herbicide-resistant weeds is quickly becoming an issue. For example, according to Dr. Larry Steckel, a weed scientist with the University of Tennessee, resistant Palmer amaranth cost Tennessee soybean growers more than $200 million in the past two years in increased herbicide costs, application ex­penses and yield loss.

Seeds Of Discontent

And if the plants themselves aren’t bad enough, ag retailers and their grower-customers need to be equally concerned with the seeds these herbicide-resistant weeds produce. According to Willowood USA’s Dr. Jeff Stachler, one waterhemp plant discovered in Moorhead, MN, produced 644,000 seeds. In another example, running water following a rain event in a field with Palmer amaranth present was found to contain 1 million seeds only 20 minutes after the storm.

Weed Resistance Issues Chart Weed Resistance Issues Chart

“If one plant produces 100,000 seeds with only 25% emergence and 10% of those plants survive, these resistant plants can produce up to 6.25 million plants two years later,” says Stachler.

For the most part, ag retailers understand that herbicide-resistant weeds are a major problem for their grower-customers. According to a survey recently conducted by CropLife® magazine, 79% of dealerships and cooperatives say weed resistance is a serious or very serious problem in their areas. Similarly, 51% of the grower-customers themselves view resistant weeds as a serious to very serious problem (see graphs).

The Quest For Control

When it comes to figuring out how to combat these resistant weeds, opinions from experts are varied. Some have advocated hand weeding mixed with alternatives to traditional herbicide programs as an option. “In 2010, it took 110 hours to completely hand-weed a 50-acre field, costing $33 per acre charge based upon a $15 per acre rate,” says Stachler. “In 2011, with the same herbicide program, it took only five hours to completely hand-weed this field — a cost of only $1.50 per acre.”

In other countries such as Australia, growers combating herbicide-resistant weeds have adopted an all-out war on the seeds. To achieve control here, growers have taken to baling their field trash into bundles used for livestock feed or burning this residual with flame-producing equipment that is pulled along behind the harvester.

Thankfully, here in the U.S., the situation isn’t quite as extreme just yet and 81% of ag retailers polled by CropLife® say they presently have the tools and knowledge needed to help growers manage their resistance issues.

However, as Penn State’s Lingenfelter says, ag retailers shouldn’t count on a completely new herbicide to come along and solve the problem of resistant weeds. “There have been plenty of new products introduced into the market to combat resistant weeds over the past few years,” he says. “But none of these offer a new mode of action option. The fact of the matter is there has been no new mode of action introduced into the herbicide market for the past 20 years. And even if a new molecule was discovered tomorrow that might offer a new mode of action for weed control, it wouldn’t be available for use on the market for another 10 years or better.”

Instead, says Willowood’s Stachler, retailers and growers should get used to viewing weeds in the field in a whole new light. “It is best to assume that any plant of single species present in a field is resistant at some level,” he says.

Topics:

Leave a Reply

Weed Resistance Stories

Weed ResistanceWeeds: The Fearsome Five
October 1, 2013
Although there are currently dozens of weeds that show some kind of resistance to herbicides, these five are the most troublesome. Read More
Weed ResistanceWeed Management Program Profiles
October 1, 2013
Here’s quick look at weed control strategies and their cost. Read More
Weed ResistanceRecognizing Resistance
October 1, 2013
Recognizing the presence of herbicide-resistant weeds and formulating a total management plan is becoming more important than ever. Read More
Mature Waterhemp in Corn
Weed ResistanceWhen Weed Control Goes Wrong
October 1, 2013
Beyond the possibility of resistance developing, ineffective control exacts cost to growers in lost yield. Read More
Top 100 Articles
Crop InputsLand ‘O Lakes, United Suppliers Finalize Merger
August 24, 2015
According to a press release on August 24, owners of United Suppliers, Inc. and members of Land O’Lakes, Inc. “have Read More
West Central Cooperative, Jefferson, IA
CropLife 100Iowa Cooperatives To Explore Unification
August 19, 2015
The boards of directors at two of Iowa’s leading farmer-owned cooperatives yesterday signed a letter of intent to study the Read More
CropLife 100Southern States Coop Hosting Drone Flight This Friday
August 3, 2015
Southern States Cooperative — No. 9 on the CropLife 100 — is hosting an FAA-approved drone demonstration at Grandview Farms Read More
CropLife 100Aligned Ag Distributors Adds Four New Owners
July 30, 2015
Aligned Ag Distributors LLC has announced the addition of four new customer/owners to Franklin Holding Co. LLC. They are: The Read More
CropLife 100Pinnacle Purchases California-Based Specialty Crops Retailer
July 20, 2015
Pinnacle Agriculture Holdings has successfully acquired California-based NH3 Service Co.  Operating as part of Pinnacle’s Performance Agriculture brand, the new locations Read More
Asmus Farm Supply liquid fertilizer facility features 20,000 square feet
CropLife 100Slideshow: Asmus Farm Supply Shows Off Its New Liquid Fertilizer Facility
July 15, 2015
Asmus Farm Supply, Rake, IA, recently added a new liquid fertilizer facility to its company operations. The new liquid fertilizer Read More
Latest News
Crop InputsBayer CropScience: A Decade Of Innovation
September 3, 2015
BLAMS! It’s not a sound effect from the pages of a Superhero comic book. Instead this nifty acronym is used Read More
ManagementReviewing MAGIE 2015
September 2, 2015
CropLife Editor Eric Sfiligoj talks what he saw at the recent Midwest AG Industries Exposition (MAGIE) show. Read More
Melissa Olds Dow AgroSciences
Crop InputsDow AgroSciences: Highlighting The Past, Present & …
September 2, 2015
In general, media events held by large agricultural suppliers tend to focus primarily on what plans the company has in Read More
Mobile tablet
OpinionTaking Data Head On
September 2, 2015
As you read this column, I’m hoping that if you picked up the phone and gave me a call, you’d Read More
Young soybean field
Industry NewsArysta LifeScience Announces New Business Unit Head For…
September 1, 2015
Arysta LifeScience North America announces the addition of Rico Christensen, Business Unit Head, North America. Christensen will have responsibility for Read More
Wilbur Ellis Pink Soybean Seed Treatment
Crop InputsWilbur-Ellis Goes Pink With Soybean Seed Treatments For…
September 1, 2015
This past year, proceeds of pink-dyed soybeans treated and sold to Wilbur-Ellis seed customers in Chester, SD, went to two Read More
SprayersNORAC Active Wing Roll Slated For More Sprayers
September 1, 2015
NORAC Systems, a member of the Topcon Positioning Group, announces the release of Active Wing Roll for RoGator, Apache, New Read More
Syngenta Sign
FungicidesSyngenta’s Newest Fungicide Receives EPA Approval
September 1, 2015
Syngenta announced today that its newest succinate dehydrogenase inhibitor (SDHI) fungicide – Solatenol – has received registration from EPA and Read More
Flooded corn in Indiana
Crop InputsDelaying The Fertilizer Decision
September 1, 2015
Comments gathered from several retailers recently evidenced a classic good-news-bad-news scenario. Good news is prices and supplies of nitrogen, phosphate, Read More
StewardshipBee Buffer Strip Initiative Seeks 100 Ohio Farmers
August 31, 2015
The U.S. Bee Buffer Project, an initiative of the Pollinator Partnership (P2), Burt’s Bees and The Burt’s Bees Greater Good Read More
2015 ShowStopper Award, MAGIE
EquipmentA ShowStopper From Case IH: The Patriot 2250
August 31, 2015
For nine years now, visitors to the yearly Midwest AG Industries Exposition (MAGIE) show have been tasked with not only Read More
Crop InputsMonsanto, FMC Expand Roundup Ready PLUS Platform
August 31, 2015
FMC Corp. and Monsanto Co. announced today an expanded agreement to continue their participation in the Roundup Ready PLUS Crop Read More
Deere Nutrient Applicator
Eric SfiligojThe Good & Bad News From MAGIE
August 31, 2015
As I write this column, I’ve just returned from the annual Midwest AG Industries (MAGIE) trade show in Bloomington, IL. Read More
CPS Morenci receiving its 4R certification
StewardshipCPS Morenci Becomes First Michigan Facility Certified I…
August 31, 2015
The 4R Nutrient Stewardship Certification Program has announced that Crop Production Services, Inc.’s facility located in Morenci, MI, has been Read More
EquipmentDeere Announces Soucy Track Distribution Alliance
August 28, 2015
John Deere announces an alliance with Soucy Track to sell and distribute products through the John Deere dealer channel. “This Read More
FertilizerFall-Applied Phosphorus: A Rooted Investment
August 28, 2015
As commodity prices decrease and input prices continue to rise, farmers are seeking more efficient strategies for meeting a high Read More
Monsanto Sign
Crop InputsWhat’s Next For Monsanto, Syngenta?
August 28, 2015
After dropping its $47 billion bid to take over Swiss agribusiness firm Syngenta, Monsanto may be turning its focus to Read More
Golden Harvest Corn stalks
Crop InputsMonsanto: Syngenta Not The Only Horse In Crop Protectio…
August 28, 2015
Monsanto Co, having ditched an audacious $46 billion (£30 billion) offer for Syngenta AG, may downshift to a humbler strategy Read More