New Herbicide-Resistant Weed Confirmed In Ohio

A weed known to many cotton and soybean growers in the South as “pigweed on steroids” has been spotted in Ohio, prompting Ohio State University Extension experts to warn Ohio growers to take measures to prevent its further spread statewide.

Palmer amaranth, which is a glyphosate-resistant weed that has had a substantially negative impact on crop yields and profitability for cotton and soybean growers in Southern states, has been spotted in a large field near Portsmouth in extreme southern Ohio, said Mark Loux, an OSU Extension weed specialist.

The concern about glyphosate-resistant Palmer amaranth, which has caused entire cotton and soybean fields to be mowed down in some Southern states, is that if the weed takes hold in Ohio crop fields, it will be even harder to control than the glyphosate-resistant weeds already present statewide, he said.

“Not only is Palmer amaranth resistant to glyphosate, this weed’s rapid growth, large size, extended duration of emergence, prolific seed production and general tolerance to many herbicides makes it a much more formidable weed to deal with than the pigweed species we already have here in Ohio,” Loux said. “Among the weeds that we already deal with, Palmer amaranth is going to require pre- and post-emergence applications, possibly multiple post-emergence applications.

“It’s already resistant to two of the main types of herbicides we use in soybeans, glyphosate and ALS inhibitors, and the weed has to be less than four inches tall when spraying in order to get control of it.”

Palmer amaranth, which can grow 3 inches a day, can release nearly a half-million seeds per plant. And because the weed is glyphosate-resistant, many growers in Southern states, in addition to spraying, have had to hire workers to go into their fields to chop down the weeds with hoes and pull them by hand.

Losses for growers dealing with this aggressive weed have been in the millions in lost agricultural crops, experts estimate.

The weed, which has typically been prevalent in Southern states, is moving north, with several other suspected cases statewide that OSU Extension experts are investigating. New infestations of Palmer amaranth have also been found farther north, in Michigan and Indiana, he said.

“We suspect Palmer amaranth was introduced in Ohio and other states through contaminated cottonseed shipped from the southern U.S. for use as animal feed here in the Midwest,” Loux said. “Palmer amaranth established from manure spread on fields that was obtained from these animal operations.”

To prevent further spread and growth of the weed in Ohio, growers and producers should avoid spreading manure on crop fields obtained from animal operations where cottonseed was used as feed, he said.

“This manure likely contains Palmer amaranth and should not be spread on crop fields,” Loux said. “To avoid that problem, growers and producers should ask if cottonseed was used as feed before using any manure obtained from an animal operation other than their own.”

The goal is to prevent the spread of Palmer amaranth, considering that Ohio already has healthy populations of glyphosate-resistant marestail (also known as horseweed), giant ragweed, common ragweed and waterhemp, he said.

“Palmer amaranth is a very competitive weed that can reduce soybean yields,” Loux said. “If you let it go, it could have a pretty explosive population increase in a very short period of time.

“It is a very expensive and difficult weed to manage.”

And the record dry, hot weather Ohioans have experienced this summer hasn’t made controlling glyphosate-resistant weeds any easier. Extended hot, dry weather and drought impact the germination, growth, hardiness and competitive ability of weeds and complicate control efforts, he said.

During extended dry conditions, weeds grow more slowly and also develop thicker cuticles on the leaf surfaces, which has the overall effect of reducing herbicide movement into and throughout the plant.

This as Ohioans have suffered through multiple days of record-setting temperatures of over 100° this summer, with scant rainfall that has resulted in most of the state except for some counties near the Kentucky, West Virginia and Pennsylvania borders experiencing moderate drought, with some counties near the Indiana and Michigan borders experiencing severe and extreme drought as of August 7, according to the most recent U.S. Drought Monitor.

And while some Ohio growers already have experienced dealing with glyphosate-resistant waterhemp, which is typically found in western Ohio and is the closest weed that Ohio has that can be compared to Palmer amaranth, the southern weed has more potential to reduce yield if it is not controlled, Loux said.

But with early diagnosis of infested fields and early intervention, the potential for damage from Palmer amaranth in Ohio can be mitigated, he said.

“This is one of those rare occasions where we have enough information to hopefully prevent additional infestations of an extremely aggressive weed, and there could be serious long-term consequences for farm profitability for failing to do so.”

Topics:

Leave a Reply

Herbicides Stories
HerbicidesScouting Key To Next Season’s Soybean Herbicide Program
August 12, 2014
When growing soybeans, growers need to think ahead to stay one step ahead of weeds. That means examining weed threats and evaluating which herbicides work best. Read More
Winter Wheat
HerbicidesArysta Touts Burndown Herbicide For Brome Management In Wheat
June 4, 2014
Arysta LifeScience North America recommends PRE-PARE Burndown Herbicide for effective brome management in winter wheat. Read More
HerbicidesFall Herbicide Applications More Effectively Manage Resistant Italian Ryegrass
May 14, 2014
Field studies show that a fall application of certain herbicides before weed emergence, leads to more successful crop planting and weed control in spring. Read More
Waterhemp in soybean stubble
HerbicidesThe Weed Resistance Problem: A Matter Of Billions
April 1, 2014
Not only is the amount of money being spent to control these yield robbers high, but the toll it has taken on the human population is growing lager by the day. Read More
Top 100 Articles
CropLife 100Pinnacle Agriculture Acquires Minnesota Retailer
April 14, 2015
Pinnacle Agriculture Holdings, LLC, ranked No. 6 on the CropLife 100,  has successfully acquired Liebl Ag, LLC in Ada, MN.  Read More
CropLife 100CHS, Aurora Cooperative Complete Fertilizer Storage, Grain Shuttle Loading Facility
April 13, 2015
CHS Inc., the nation’s leading cooperative and ranked No. 5 on the CropLife 100, and Aurora Cooperative (ranked No. 21) Read More
CropLife 100GROWMARK Acquires Missouri Refined Fuels Terminal
April 2, 2015
Bloomington, IL-based GROWMARK and Magellan Pipeline Co. have entered into an agreement in which GROWMARK will acquire the refined fuels Read More
CropLife 100Wilbur-Ellis Acquires South Dakota Retailer
April 2, 2015
Wilbur-Ellis Co.’s Agribusiness Division, a recognized leader in precision agriculture technology and the distribution and marketing of plant protection, seed Read More
CropLife 100The McGregor Co. Closes Smith-Kem Acquisition
April 2, 2015
The McGregor Co. — ranked No. 16 on the CropLife 100 list of largest U.S. ag retailers — has completed Read More
CropLife 100BRANDT Commemorates National Ag Day
March 20, 2015
The Illinois agriculture community gathered at BRANDT global headquarters on March 18 to celebrate National Ag Day behind this year's theme Sustaining Future Generations. Read More
Latest News
FertilizerSimplot’s Gal-XeONE Technology Moves West
April 27, 2015
The J.R. Simplot Co. remains committed to creating customer value through technology. In 2013, Simplot purchased the Gal-XeONE controlled release Read More
Eric SfiligojThe Need To Defend Production Agriculture
April 27, 2015
Last week, I spent the better part of my time on the road visiting with ag retailers and market suppliers Read More
FertilizerStarter Fertilizers Show Value In Stressful Spring Cond…
April 27, 2015
From wet, cold conditions in the eastern Corn Belt to excessively dry, cool soils in the Plains states, spring field Read More
StewardshipTFI Announces Renewed Financial Commitment To Fertilize…
April 24, 2015
Today, The Fertilizer Institute’s (TFI) President Chris Jahn announced that TFI and over 100 partners will more than double existing Read More
Industry NewsMACA Names New Ambassador Coordinator
April 23, 2015
The Mid America CropLife Association (MACA) has named Michelle Kilper as its new Ambassador Coordinator. Michelle is a graduate of Read More
ManagementAg Retailer’s Role In Local Policy Making; Raising The …
April 23, 2015
CropLife’s Paul Schrimpf and Eric Sfiligoj review their recent travels, precision ag efforts in Washington, DC, and the role of Read More
TMX-2050 In-Cab Display Launch Run Screen
Precision AgIn-Cab Computing 2015: Connectivity, Compatibility Take…
April 23, 2015
In terms of in-cab computing solutions for the agriculture market, companies like Case IH, Topcon, Trimble, John Deere and Raven Read More
USDA
StewardshipUSDA Outlines Building Blocks For Climate Smart Agricul…
April 23, 2015
Today, the USDA has announced a comprehensive and detailed approach to support farmers, ranchers, and forest land owners in their Read More
Industry NewsArysta LifeScience Welcomes New Territory Sales Manager
April 23, 2015
Arysta LifeScience North America recently announced the addition of Kaitlyn Acaster to the Canadian sales team. Acaster will fill the Read More
Crop InputsMarrone Bio Innovations Opens New Research Greenhouse
April 23, 2015
Marrone Bio Innovations, Inc. (MBI), a leading provider of bio-based pest management and plant health products for the agriculture, turf Read More
Crop InputsDuPont Acquires Taxon Biosciences
April 23, 2015
DuPont has agreed to acquire Taxon Biosciences, Inc., a leading microbiome discovery company. This acquisition will build on DuPont’s in-house capabilities Read More
Farmer on tablet
ManagementStudy: Consumers Don’t Care If U.S. Farmers Feed …
April 23, 2015
“We’re feeding the world” is a mantra often used by those involved in farming and food to build support for Read More
Industry NewsCorporate Responsibility Magazine Names Monsanto One Of…
April 22, 2015
Corporate Responsibility Magazine (CR Magazine) named Monsanto Co. to its 100 Best Corporate Citizens List for 2015. This is the Read More
FertilizerSpring Nitrogen Management: Form And Timing
April 22, 2015
Most corn producers have planned their spring nitrogen program for 2015, and many have already started to implement their program. Read More
FMC 3Rive 3D
Industry NewsFMC Corp. Completes Acquisition Of Cheminova
April 22, 2015
FMC Corp. has completed the closing of its acquisition of Cheminova A/S, a multinational crop protection company based in Denmark Read More
SoftwareSyngenta Expands AgriEdge Excelsior Nationwide For 2015
April 22, 2015
Growers across the country can now take the guesswork out of improving their farm’s production, land value, farm stewardship and Read More
Cornfield near Sioux City Iowa
HerbicidesU.S. Regulators May Start Testing Food For Glyphosate R…
April 21, 2015
U.S. regulators may start testing food products for residues of the world’s most widely used herbicide, EPA told Reuters’ Carey Read More
FungicidesBRANDT Adds Zonix Biofungicide To Portfolio
April 21, 2015
BRANDT has added Zonix biofungicide to its rapidly expanding line of organic and sustainable products. Zonix is a contact fungicide that Read More