Weed Scientist: Giant Ragweed Latest Concern For Farmers

When it comes to weed pests, glyphosate-resistant waterhemp tops the list, but resistant giant ragweed may be the challenger, according to a University of Missouri Extension weed scientist.

“Giant ragweed certainly has my attention,” Kevin Bradley, University of Missouri Extension weed scientist, told pest management field day visitors at MU Bradford Farm. “We’ll focus our research on giant ragweed, both resistant and not.”

Bradley considers the resistant waterhemp a statewide problem. “We’re not focusing on anymore surveys of waterhemp,” Bradley says. “I’m confident it is just about everywhere corn and soybeans are grown.”

On the most recent survey, when waterhemp was tested from 144 locations across the state, 58 percent of the populations were resistant to glyphosate. A new survey tested giant ragweed from 27 farms, with 12 found glyphosate-resistant.

Bradley collects weed seeds in the fall from random fields, not just those suspected of having resistance. The seeds are grown in an MU greenhouse. At various stages weeds are sprayed with different concentrations of glyphosate or ALS herbicides. Those that thrive in spite of herbicide are labeled resistant.

“My concern is not just herbicide resistance, but multiple resistances,” Bradley says.

What started as resistance to glyphosate, the most widely used herbicide, has become resistance to other herbicides. The newly resistant giant ragweed has been found to tolerate high levels of glyphosate and to have at least moderate resistance to ALS herbicides.

“It will take a combination of herbicides to control the resistant weeds,” he says.

At another stop on the MU weed tour, Bradley said best control of weeds is obtained with a two-pass system. Herbicide is sprayed before planting to control overwintering weeds and emerging seedlings. Then the growing crop is sprayed with a post-planting application to control new weeds.

“The majority of the time this two-pass system works best,” Bradley says. “There is a definite yield advantage.”

However, new herbicide combinations with longer life show promise. “A one-pass system that includes a residual herbicide is becoming more popular with farmers,” Bradley says.

At a third stop, Bradley showed off what he calls “research that we can’t say much about.” The soybeans, mostly weed-free, are tolerant to 2,4-D herbicide, an older chemistry that was widely used for years.

“You won’t see this available commercially for a few years,” Bradley predictes. “But the 2,4-D-tolerant soybeans are very robust and tolerate 2,4-D very well.”

(Source: University of Missouri Cooperative Media Group)

Leave a Reply

2 comments on “Weed Scientist: Giant Ragweed Latest Concern For Farmers

  1. Bourquin’s Farm Mkt. & Trading Co., Inc.

    I’m contacting you to let you know we manufacture a weedpulling machine for Organic farmers called the BOURQUIN WEEDPULLER/ORGANIC WEEDPULLER. We would like to encourage you to look at our website, http://www.organicweedpuller.com and see a video of it pulling weeds.
    Then if you have any questions, give us a call.
    Thank you for your time,

    Dan and Shirley Bourquin
    [email protected]
    http://www.organicweedpuller.com
    BOURQUIN’S ORGANIC WEEDPULLER
    155 East Willow, Colby, KS 67701
    Phone: 785-462-3300
    Phone: 785-443-2774

  2. Bourquin’s Farm Mkt. & Trading Co., Inc.

    I’m contacting you to let you know we manufacture a weedpulling machine for Organic farmers called the BOURQUIN WEEDPULLER/ORGANIC WEEDPULLER. We would like to encourage you to look at our website, http://www.organicweedpuller.com and see a video of it pulling weeds.
    Then if you have any questions, give us a call.
    Thank you for your time,

    Dan and Shirley Bourquin
    [email protected]
    http://www.organicweedpuller.com
    BOURQUIN’S ORGANIC WEEDPULLER
    155 East Willow, Colby, KS 67701
    Phone: 785-462-3300
    Phone: 785-443-2774

Herbicides Stories

Palmer amaranth in soybean stubble
HerbicidesWSSA: Billions In Potential Economic Losses From Uncontrolled Weeds
May 4, 2016
What losses would corn and soybean growers experience if they were forced to eliminate herbicides and other control techniques from Read More
Spray Drift
HerbicidesRoundup Ready Xtend: Silver Linings In Label Delays For Monsanto
May 4, 2016
Since 2014, Monsanto has trained more than 20,000 growers and retailers on all aspects of its new dicamba-tolerant system at Read More
Giant Ragweed
HerbicidesSurvey Provides Insights On Giant Ragweed In The Corn Belt
May 2, 2016
A new survey published in the journal Weed Science offers insights into the distribution and management of giant ragweed, a Read More
Corn Field
HerbicidesNew Wilbur‐Ellis Herbicide Targets Volunteer Corn
April 28, 2016
Wilbur‐Ellis Co., a recognized leader in marketing and distribution of crop protection products, as well as precision agriculture technology, has Read More
Trending Articles
Eric SfiligojReasons For Hope In Commodity Prices
May 2, 2016
For many months now, the doomsayers have ruled the day in agriculture. Too much supply with too little demand would Read More
Eric SfiligojMissing The Family Ties In Agriculture
April 25, 2016
By its nature, the agriculture market is cyclical. Up and down cycles come and go with a regular pattern. For Read More
HerbicidesHerbicide Resistance In Waterhemp Continues To Grow
April 22, 2016
Twenty-five years ago, waterhemp was virtually unknown to Illinois farmers. Today, the broadleaf weed blankets corn and soybean fields across Read More
Eric SfiligojBiotech Corn Drop More Economics Vs. Consumer Rejection
April 18, 2016
Since their introduction into the agricultural marketplace, biotech crops has steadily grown in acreage in the countries of the world Read More
Crop InputsBayer: 5 Reasons We Disagree With Maryland Neonic Ban
April 12, 2016
We’re disappointed that the Maryland legislature chose not to stand up for sound science and the rights of Maryland’s homeowners Read More
Corn
OpinionChallenging Global Economic Conditions Putting More Heat On U.S. Ag Retailers
April 7, 2016
There it is. That vague, slightly sickening feeling in the pit of my stomach. Things are getting weird out there. Read More
Latest News
Young Corn Field
Crop NutritionEnhancing In-Season Nitrogen Use Efficiency Is In The D…
May 5, 2016
Spring is here and crops are in the ground. Do you have a plan for your nitrogen during the growing Read More
ID3 Air Induction Flat Spray Nozzle | Lechler
Nozzles2016 Nozzles And Tips Report: Waste Watchers
May 5, 2016
Every year in the spring, ag retailers and their grower-customers prepare for the coming crop season. This involves prepping crop Read More
Industry NewsHELM AGRO Adds New Marketing & Business Development…
May 4, 2016
HELM AGRO US, Inc. has announced the hiring of Troy Bettner as the company’s new Marketing & Business Development Leader. Bettner Read More
Palmer amaranth in soybean stubble
HerbicidesWSSA: Billions In Potential Economic Losses From Uncont…
May 4, 2016
What losses would corn and soybean growers experience if they were forced to eliminate herbicides and other control techniques from Read More
Spray Drift
HerbicidesRoundup Ready Xtend: Silver Linings In Label Delays For…
May 4, 2016
Since 2014, Monsanto has trained more than 20,000 growers and retailers on all aspects of its new dicamba-tolerant system at Read More
Syngenta headquarters in Basel, Switzerland
Crop InputsSyngenta Board Appoints New CEO
May 4, 2016
Syngenta announced today the appointment of J. Erik Fyrwald, currently President and CEO of the U.S. chemistry distribution company Univar Read More
Crop InputsIntrexon Establishes Crop Protection Enterprise
May 4, 2016
Intrexon Corp., a leader in synthetic biology, has announced the formation of Intrexon Crop Protection (ICP), a wholly-owned subsidiary dedicated to Read More
Patriot 4440 Sprayer close up
ManagementFlashing Back And Moving Forward On Spray Drift
May 3, 2016
The potential for pesticide drift remains an unavoidable feature of modern agriculture. Here, too, history repeats itself. “When Roundup debuted, Read More
Giant Ragweed
HerbicidesSurvey Provides Insights On Giant Ragweed In The Corn B…
May 2, 2016
A new survey published in the journal Weed Science offers insights into the distribution and management of giant ragweed, a Read More
Truck dumping dry fertilizer
FertilizerFertilizer Logistics Q&A: Southern States’ Joe Wlod…
May 2, 2016
Joe Wlodkoski, Director of Agronomy Procurement, Fertilizer, Southern States Cooperative, is a 40-plus year fertilizer industry veteran. He is quite Read More
Eric SfiligojReasons For Hope In Commodity Prices
May 2, 2016
For many months now, the doomsayers have ruled the day in agriculture. Too much supply with too little demand would Read More
West Central Dome structure
FertilizerFertilizer Logistics 2016: All Clear, So Far
May 1, 2016
After a relatively hairy early start to the spring fertilizer movement season with flooding in Louisiana and St. Louis, things Read More
BAICOR
CropLife 100BRANDT Acquires Utah Specialty Fertilizer Company
April 28, 2016
BRANDT, a leading agriculture retailer and manufacturer of specialty ag products, has acquired a majority interest in BAICOR, L.C. BAICOR, Read More
Soybean field
Industry NewsVerdesian Life Sciences Adds Vice President Of Business…
April 28, 2016
Verdesian Life Sciences has announced the addition of Marc Treurniet to the plant health and nutrition company’s management team. Treurniet Read More
ManagementBiotech Crops Developments and Millennials
April 28, 2016
Editors Eric Sfiligoj and Paul Schrimpf talk about the latest activities in biotech crops and a major shift in the Read More
Industry NewsNachurs-Alpine, Pathway Biologic Extend Marketing Agree…
April 28, 2016
Nachurs-Alpine Solutions (Marion, OH) and Pathway Biologic (Plant City, FL) announce an extension to their exclusive marketing agreement specific to Read More
MicronutrientsCharah Add Three Warehouses For SUL4R-PLUS Fertilizer
April 28, 2016
Charah, Inc., a total solutions company providing unparalleled service and innovation for the coal-fired power generation industry, announced today that Read More
Spenser Forgey, Yahama Fortix
FungicidesIndiana Farmer Wins Arysta LifeScience FORTIX Fungicide…
April 28, 2016
Arysta LifeScience North America recently presented Spenser Forgey, a grower from Young America, IN, with a new 2016 Yamaha Grizzly Read More