How To Manage Herbicide-Resistant Waterhemp

Take advantage of the elevated view from your combine cab to survey and assess the effectiveness of your weed management program this fall.

“A field free of weeds during harvest is very desirable and represents an outcome that will require increased management as weeds continue to adapt to modern crop production practices,” said Aaron Hager, University of Illinois Extension weed specialist.

Many observations have been made recently that waterhemp and horseweed are frequently appearing in corn and soybean fields across Illinois. Hager’s recent field visits have indicated that seed production on these mature plants has been successful, suggesting a preharvest herbicide application may do little to reduce the viability of these mature seeds.

“There are many reasons that these two particular weed species have successfully completed their life cycle in corn and soybean fields,” he said. “One reason is the occurrence of herbicide resistance. Glyphosate resistance in Illinois waterhemp and horseweed populations is known to occur, and we suspect this will become increasingly common in future growing seasons.

“Additionally, resistance to five different herbicide site-of-action families has been documented to occur in Illinois waterhemp populations. In all instances except one, these resistance traits can be transferred by movement of both pollen and seed.”

Herbicide-resistant populations generally do not infest an entire field over the course of a single growing season. Rather these populations usually begin as a small number of plants that survive to produce seed.

The next season the herbicide-resistant population may exist as a patch of weeds encompassing a small area within the field. Rogueing these plants from the field before they produce viable pollen and seed can help slow the spread of the herbicide-resistant population within the field and reduce the movement of the resistance trait to other fields, Hager said.

“Female waterhemp plants have the potential to produce in excess of one million seeds per plant, although that number is usually much smaller when the waterhemp plants have grown under competitive conditions,” he said. “If you notice a few surviving female waterhemp plants in a field, it might be a good investment of time to remove these plants before they enter the combine. Combines can spread weed seed across a field and transport seed from one field to another.”

If a herbicide-resistant waterhemp population is present or suspected in a particular field, consider harvesting that field last to prevent introducing the seed from the resistant plants into the combine and their subsequent movement to other fields, Hager suggests. Another option is to avoid patches of weeds during harvest operations.

(Source: Illinois Ag Connection)

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
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

Trending Articles

Crop InputsPlatform Specialty Products To Acquire Arysta LifeScience
October 20, 2014
Once the acquisition is complete, Platform Specialty Products will combine Arysta LifeScience with previously acquired companies Agriphar and Chemtura Crop Solutions. Read More
Seed/BiotechMonsanto Offers New Support For Ferguson, Area Communities
October 8, 2014
Monsanto Co. has committed $1 million in new support for several collaborative efforts in Ferguson, MO, and surrounding communities in North St. Louis County. Read More
Seed/BiotechUnapproved Genetically Modified Wheat Found In Montana
October 3, 2014
USDA reports that one year after discovery of Monsanto's unapproved wheat in a single Oregon field disrupted U.S. wheat export sales, the GMO wheat has again been found in Montana. Read More
Equipment2014 Product Of The Year Voting
September 19, 2014
The deadline to vote for the 2014 CropLife IRON Product of the Year is October 31. Please cast your vote today to help us determine the winner. Read More
FertilizerFall Fertility 2014: Forecasting Fertilizer Use
September 7, 2014
Great crops this year have tapped the soil, and fall work is definitely called for, but how challenging will that get? Read More
CropLife 100CHS To Build $3 Billion Fertilizer Plant In North Dakota
September 5, 2014
The fertilizer plant in Spiritwood will be the single largest investment in CHS history, as well as the single largest private investment project ever undertaken in North Dakota. Read More

Latest News

ManagementGreenfield Scholars Program Aims To Sustain Agronomy Wo…
October 21, 2014
The program encourages talented students to study agronomy, crop and soil sciences while cultivating networks to develop the necessary workforce to sustain the profession. Read More
Paul SchrimpfPrecision Ag: Taking It To The Hill
October 21, 2014
A new coalition took the good news message of precision agriculture to Washington, DC, last month. Read More
ManagementUSDA Awards $18 Million In Small Business Research Gran…
October 21, 2014
The grants will provide high quality, advanced research and development that will lead to technological innovations and solutions for American agriculture. Read More
FertilizerCF Industries Terminates Merger Discussions With Yara I…
October 21, 2014
CF Industries Holdings and Yara International have terminated their discussions regarding a potential merger of equals transaction. Read More
Seed/BiotechSyngenta Ranked A Top 10 Biotech Employer For Third tim…
October 20, 2014
Syngenta ranked in the top 10 among the world’s top biotech employers, according to an annual survey conducted by Science magazine. Read More
CropLife 100Wheat Growers Break Ground For New Facility At Kennebec
October 20, 2014
Wheat Growers has broke ground for a state-of-the-art shuttle loader grain handling, fertilizer and agronomy facility in Kennebec, SD. Read More
FertilizerVerdesian Life Sciences Signs Agreement With Los Alamos…
October 20, 2014
Verdesian Life Sciences has signed a licensing agreement with Los Alamos National Laboratory to develop and market LANL’s latest nitrogen enhancement technology for plants. Read More
MicronutrientsStoller Group Announces Groundbreaking At New Office Bu…
October 20, 2014
Jerry Stoller, founder and president of Stoller Group, announced the groundbreaking at the site of the company’s future headquarters in Read More
Crop InputsBioSafe Systems Opens New Production Facility In Nevada
October 20, 2014
BioSafe Systems has completed construction of a state-of-art production facility in Sparks, NV, for its line of activated peroxygen products. Read More
Crop InputsPlatform Specialty Products To Acquire Arysta LifeScien…
October 20, 2014
Once the acquisition is complete, Platform Specialty Products will combine Arysta LifeScience with previously acquired companies Agriphar and Chemtura Crop Solutions. Read More
Seed/BiotechEPA Approves Dow’s Enlist Duo Herbicide
October 15, 2014
The Enlist Weed Control System, breakthrough technology to fight resistant and tough weeds, has received the long-awaited green light from federal regulatory authorities. Read More
MicronutrientsGypsum On Farms Could Help Keep Water Clean, Not Green
October 14, 2014
Gypsum, which has roots in the past as a farm soil treatment, also may have a bright future, and not just as a booster of crops but also as a protector of water. Read More
Photo credit: The United Soybean Board/The Soybean Checkoff.
Crop InputsVerdesian Grows Sales Staff
October 14, 2014
The new account managers will drive sales growth and support relationships with key customers in the plant nutrition and seed treatment and inoculants product categories. Read More
WebinarsUpcoming Webinars
October 14, 2014
Register for one of our upcoming Webinars or access our archive of past Webinars to view recordings of presentations that may be of interest to you. Read More
CropLife 100The Andersons Purchases Six Grain Elevators, Four Agron…
October 14, 2014
The Andersons has acquired Auburn Bean and Grain of Auburn, MI, which will increase the storage capacity of its Grain Group by about 13%. Read More
StewardshipThree Ohio Ag Retailers Honored With 4R Certification
October 13, 2014
The 4R Nutrient Stewardship Certification Program has announced its first three agriculture nutrient service providers to achieve certified status. Read More
Eric SfiligojEntering Agriculture’s New Phase
October 13, 2014
The market’s giddy ride the past few years might be coming to an end in 2015, warns one industry insider. Read More
Eric SfiligojWar And Green Peace
October 11, 2014
A one-time member of Green Peace recently explained why he left the organization after 15 years. Read More