Know Your Enemy: The Importance Of Weed Identification

A recent BASF survey found that 76% of growers have made changes to their weed management programs to address weed resistance. With this growing problem spreading across the U.S., it is important to take a comprehensive approach to fighting resistance and controlling weeds. Proper weed identification is fundamental to any effective weed control program.

“The first step in weed control is to know your enemy,” said Kevin Bradley, Ph.D., Associate Professor of plant sciences at the University of Missouri. “If you don’t know what you’re going after, you’re probably going to be behind from the very beginning.”

Scouting should be done early in the season, when weeds are easier to control. Later in the season, those weeds continue to grow and produce seed, further contributing to weed seed banks.

Often, the same weed species will show up in a field year after year, so it is important to know where problem weeds live.

“It’s about characterizing which part of your farm needs certain attention,” said Greg Armel, Technical Market Manager, BASF. “There’s an adage – every year you don’t control weeds, there will be seven more years of fighting that weed. The less you know about what you’re dealing with, the more that weed has a chance to get a foothold in your ground and prevent you from controlling it in an effective manner.”

Newly acquired land, or any major land management changes, requires special attention when scouting and identifying weeds.

“Anything new you might have done to a field, like spread manure or taken ground out of pasture, makes it more critical to know exactly which species are present so you can make the right herbicide selection and get a good program established,” said Bradley.

Palmer Amaranth vs. Waterhemp

While waterhemp has been an established problem for growers, it’s more aggressive “cousin,” Palmer amaranth, has been making its way into growers’ fields. These two weeds can be easily confused. Here are a few tips for identifying Palmer amaranth:

•  Look for long cotyledons – the first two leaves. Palmer amaranth has the longest cotyledons compared to any other pigweed or waterhemp species.

•  Palmer amaranth leaves will be shorter and more rounded compared to waterhemp leaves, which are oar-shaped and glossy.

•  Palmer amaranth has larger brachts than waterhemp. Brachts are the modified leaves associated with the inflorescence of plants. The brachts on female Palmer amaranth plants have a spine-like appearance.

•  The petioles – stem-like structures that anchor leaves – are much larger on Palmer amaranth than other pigweed and waterhemp species. Often the petiole is as long or longer than the leaf.

Foxtail species

Though giant foxtail is the most common foxtail affecting crops in the United States, pockets of green and yellow foxtail have made appearances as well. It is very important to identify which foxtail species you are up against. Yellow foxtail is not easily controlled by certain ALS-inhibiting herbicides, and green foxtail is not easily controlled by certain HPPD-inhibiting herbicide. Giant foxtail is generally the easiest species to control.

• All foxtail species have a fringe of hair at the ligule, a helpful identifier when comparing to similar grasses.

• Giant foxtail has small hairs all over its leaf surface.

• Green foxtail has no hairs on its leaf structure, other than the ligule.

• Yellow foxtail has half-inch long hairs just above the ligule and is smooth over the rest of the leaf surface.

Weed identification is essential to proper weed control. Remember to scout your fields early and often throughout the season.

For more quick tips on weed control, visit AdvancedWeedControl.basf.us.

Topics:

Leave a Reply

Crop Inputs Stories

Radish cover crop taproot
Crop InputsSoil Health Institute, Datu Research Receive Grant To Evaluate Economic Impact Of Soil Health Practices
December 1, 2016
The Soil Health Institute (SHI) and Datu Research has announced a $626,000 grant from the Walton Family Foundation to quantify Read More
Young soybean field
HerbicidesLiquid Formulation Valor EZ Herbicide Available For 2017
December 1, 2016
Valent U.S.A. Corp. has released Valor EZ; a liquid formulation of the company’s leading herbicide, Valor. Named Valor EZ Herbicide Read More
Corn
InsecticidesMajor Review Finds Neonic Poses Low Risk To Aquatic Invertebrates
November 28, 2016
A major new ecotoxicological review and risk assessment has been published in the peer-reviewed literature and concluded that registered crop Read More
FertilizerNutrient Management, Conservation Among Topics Covered At Indiana CCA Conference
November 23, 2016
Certified crop advisers, consultants, farmers, agribusiness professionals and students will learn more about nutrient management, soil and water conservation, pest Read More
Trending Articles
Precision AgTrimble Debuts End-to-End FMIS Platform
November 28, 2016
October’s inaugural PrecisionAg Vision Conference left this author with many thoughts and things to ponder in the coming months. Probably Read More
CHS Primeland
CropLife 100The 2016 CropLife 100 Report: Reviewing The Many Bulls And Bears Impacting This Year’s Marketplace
November 28, 2016
For virtually all of 2016, the nation was wholly focused on the big Presidential election. Some folks aligned themselves with Read More
Monsanto sign
Crop InputsMissouri Governor Meets With Bayer CEO To Discuss Monsanto Merger
November 21, 2016
Missouri Gov. Jay Nixon visited Bayer AG global headquarters in Leverkusen, Germany, on November 18 to discuss the proposed Bayer-Monsanto Read More
STS16 2017
SprayersHagie Manufacturing Releases 2017 STS16 Sprayer To Market
November 16, 2016
Hagie Manufacturing LLC’s largest full season applicator is now available with enhancements for the 2017 model year. Hagie is officially Read More
Wilco
CropLife 100Valley Agronomics, Wilco-Winfield To Form New Agronomy Joint Venture
November 11, 2016
Valley Agronomics LLC, headquartered in Rupert, ID, is a joint venture between Valley Wide Cooperative and Winfield Solutions, LLC. Wilco-Winfield, Read More
FertilizerThe Fertilizer Institute Issues Statement On The U.S. Elections
November 10, 2016
The Fertilizer Institute (TFI) President Chris Jahn has issued the following statement on the results of the 2016 elections: “TFI Read More
Latest News
ManagementCorn and soy planting update; Takeaways from Climate Co…
December 2, 2016
AgriBusiness Global Editor Dave Frabotta Joins Paul Schrimpf for a discussion of global corn and soybean planting trends, and a Read More
Radish cover crop taproot
Crop InputsSoil Health Institute, Datu Research Receive Grant To E…
December 1, 2016
The Soil Health Institute (SHI) and Datu Research has announced a $626,000 grant from the Walton Family Foundation to quantify Read More
Mike Stern
Precision AgClimate Corp. CEO Talks Retailer Support For Digital Ag
December 1, 2016
CropLife Magazine’s sister publication, AgriBusiness Global, recently sat down with Mike Stern, CEO of The Climate Corp., following the Monsanto subsidiary’s Read More
ManagementAg Industry Comes Together To Address Climate Change
December 1, 2016
Addressing climate change — and more specifically, decreasing greenhouse gas emissions from agriculture — can only be achieved through collective Read More
Young soybean field
HerbicidesLiquid Formulation Valor EZ Herbicide Available For 201…
December 1, 2016
Valent U.S.A. Corp. has released Valor EZ; a liquid formulation of the company’s leading herbicide, Valor. Named Valor EZ Herbicide Read More
Key Cooperative Marcus Construction Steel Building
ManagementThe Value Of Cooperatives In Modern Agriculture
December 1, 2016
Editor’s Note: Jaxon Mullinnix of  Lone Tree, IA, was recently named the Iowa state winner of the 2017 GROWMARK essay Read More
AGCO Operator of the Year Tony Kornder
SprayersAGCO Names Tony Kornder Operator Of The Year
December 1, 2016
AGCO Corp. names Tony Kornder with Genesis Growing Solutions in Le Sueur, MN, the 11th annual Operator of the Year. Read More
Chris Henney OABA
ManagementOABA Industry Conference To Provide Outlook For Future …
November 29, 2016
The upcoming Ohio AgriBusiness Association Industry Conference is packed with widely-respected speakers and industry professionals, sharing their expertise on a Read More
Corn
InsecticidesMajor Review Finds Neonic Poses Low Risk To Aquatic Inv…
November 28, 2016
A major new ecotoxicological review and risk assessment has been published in the peer-reviewed literature and concluded that registered crop Read More
EquipmentGSI Details New Grain Drying Efficiency System for Coop…
November 28, 2016
Grain elevators and ag co-ops are always looking for ways to increase their energy efficiency to help improve profitability. For Read More
Precision AgTrimble Debuts End-to-End FMIS Platform
November 28, 2016
October’s inaugural PrecisionAg Vision Conference left this author with many thoughts and things to ponder in the coming months. Probably Read More
AGCO AgControl system
Precision AgPrecision Ag Technology: Rate Control For The Times
November 28, 2016
It’s not surprising that the need for more economical, effective application is driving the demand for the latest rate controllers Read More
ARA
Eric SfiligojTaking The Industry’s Pulse At ARA
November 28, 2016
When most of you read this particular column, many of the industry’s key folks will probably be spending at least Read More
CHS Primeland
CropLife 100The 2016 CropLife 100 Report: Reviewing The Many Bulls …
November 28, 2016
For virtually all of 2016, the nation was wholly focused on the big Presidential election. Some folks aligned themselves with Read More
FertilizerNutrient Management, Conservation Among Topics Covered …
November 23, 2016
Certified crop advisers, consultants, farmers, agribusiness professionals and students will learn more about nutrient management, soil and water conservation, pest Read More
Monsanto sign
Crop InputsMissouri Governor Meets With Bayer CEO To Discuss Monsa…
November 21, 2016
Missouri Gov. Jay Nixon visited Bayer AG global headquarters in Leverkusen, Germany, on November 18 to discuss the proposed Bayer-Monsanto Read More
Arysta LifeScience
Crop InputsArysta LifeScience Forms Alliance With Beem Biologics
November 21, 2016
As part of its recently announced strategy to become a leader in high-value, high-growth specialty market segments in the crop Read More
DuPont sign
Crop InputsDuPont To End Pension Contribution For Active Employees
November 18, 2016
DuPont will no longer contribute to active employees’ pension plans, a move that will affect the retirement of 13,000 workers, Read More