Control Weeds Next Year … By Starting This Year

There have always been two objectives to weed control. The first is obvious: keeping weeds from taking moisture and nutrients from this year’s cotton. The second is less obvious, but equally important: keeping weeds from going to seed and affecting next year’s crop.

A weedy field this year is more apparent and more immediate, but in this age of growing resistance to herbicides, it is increasingly important to control weeds and keep them from going to seed.

The situation is best exemplified in the Palmer amaranth species of pigweed that has developed resistance to glyphosate in some areas.

“Morningglory is our most common weed and it’s the driving force behind the use of ET at layby, but the resistant amaranth is the one we need to watch for,” says Dr. Stanley Culpepper, Georgia Extension agronomist. “Each resistant weed that makes it to harvest can shed thousands of seeds, and those seeds can stay in the soil for years.”

ET is a broad-spectrum herbicide from Nichino America.

Digging in the Dirt

There are herbicides that are still effective against resistant pigweed, but in some cases growers have resorted to digging up weeds by hand. “We have a little bit of that here,” says Howard Cross, a cotton grower in Pinehurst, GA. “We’ve had to go out and dig up a few glyphosate-resistant weeds by hand.”

Not everyone has to go that far, says Culpepper. His specific recommendations are available at www.gaweed.com, or at Georgia Extension offices.

Every weed has the potential to develop resistance, and within each species is enough genetic diversity to ensure that at least a percentage will be naturally resistant to a particular herbicide. If those weeds are allowed to survive, they can pass the resistance on to the next generation.

Doing a solid job at burndown, including a second if-necessary burndown application, is the way to start an effective resistance management program. After that, it’s back to basics – using a residual herbicide at planting and a post-directed herbicide at layby.

ET Phone Home

ET at burndown, postemergence or at layby is an excellent tank-mix partner if a grower has bindweed, morningglory, lambsquarter or pigweed in his field, says Ricky Sloan, of Helena Chemical in Moultrie, GA. “ET does a good job on those weeds, plus it heats up the tank mix,” he says.

Sloan avoids Roundup altogether at layby and recommends 1 quart of MSMA, 0.5 to 0.75 ounces of ET per acre, and a quart of mentholated seed oil per 100 gallons of water. If growers want to add a residual herbicide, he recommends adding a quart of diuron per acre. Sloan says these tank-mixes combine the strengths of each herbicide, while avoiding overuse of glyphosate.

The goal is to have a clean field at harvest so that weeds don’t go to seed. Ideally, after layby the canopy will closes and weed seed cannot germinate. But in dry years, canopies may not close and late-season weeds can cause problems.

If that’s the case, then ET can again provide some options. “ET is also registered as a defoliant, so if I see any morningglory, I add ET to the tank mix,” says Cross. “It gives good defoliation, and it keeps the morningglories from going to seed.

Editor’s note: Some information for this story was provided by Nichino America.


Add 2 photos to captions:
Ricky Sloan
Palmer amaranth produces millions of seed.

Leave a Reply

Weed Control Stories
Insect Control

Genome Mapping Signals Brighter Days for U.S. Cotton

December 6, 2014

At a time when growers rely increasingly more on genetic advancements in yield and fiber quality to keep cotton economically viable, cotton breeders and researchers are excited about the possibilities that genome mapping brings to variety and trait development.

Product News

Brake Herbicide Receives Section 18 Approvals in Six States

February 18, 2015

Brake Herbicide has received Section 18 emergency use exemptions for control of glyphosate-resistant Palmer amaranth in six cotton producing states.

Product News

USDA Deregulates Dicamba-Tolerant Technologies for Cotton and Soybeans

January 16, 2015

The USDA has announced its decision to deregulate Bollgard II XtendFlex cotton and Roundup Ready 2 Xtend soybeans – Monsanto’s dicamba-tolerant trait technologies for those crops.

Product News

Monsanto and FMC Renew and Broaden Crop Protection Agreement

January 8, 2015

Monsanto and FMC have agreed to extend and broaden their current relationship to help benefit cotton, corn and soybean growers through Roundup Ready PLUS Crop Management Solutions.

News

Details from Summit on “Wicked” Herbicide Resistance Problem Now Available Online

October 21, 2014

Slides and a webcast of the Weed Science Society of America’s scientific summit on herbicide resistant weeds are now available for free online.

Crop Inputs

Consider Options for Fall Herbicide Applications

October 7, 2014

Growers who may be considering fall herbicide applications for anything other than Italian ryegrass may want to rethink their options.

Crop Inputs

FMC to Acquire Cheminova

September 8, 2014

Auriga Industries has agreed to sell its wholly-owned subsidiary Cheminova to FMC Corporation.

Around The Gin
Product News

New Cheminova Chemistry to Help Control Herbicide Resistant Weeds

February 23, 2015

Cheminova plans to register pethoxamid, a new herbicide active ingredient, to help growers manage herbicide-resistant weeds.

Product News

Brake Herbicide Receives Section 18 Approvals in Six States

February 18, 2015

Brake Herbicide has received Section 18 emergency use exemptions for control of glyphosate-resistant Palmer amaranth in six cotton producing states.

Precision Technology

TeeJet Matrix 430 Provides Simple, Easy-to-Use Guidance

February 18, 2015

TeeJet Technologies’ new Matrix 430 GNSS guidance system is ideal for a wide range of field applications.

Precision Technology

TeeJet Launches RX520 High-Precision GNSS Receiver

February 17, 2015

TeeJet Technologies has introduced the RX520 dual frequency GNSS receiver for precision farming operations.

Disease Control / Nematodes

Velum Total Approved for Cotton, Peanuts in 2015

February 12, 2015

Bayer CropScience has received registration for Velum Total, a new insecticide/nematicide for use in cotton and peanuts in 2015.

Disease Control / Nematodes

EPA Approves TOPGUARD Terra for Cotton Root Rot Control

February 6, 2015

TOPGUARD Terra fungicide from Cheminova has received EPA registration for control of cotton root rot.

Product News

Deltapine to Release Five Bollgard II XtendFlex Cotton Varieties

January 27, 2015

Following USDA deregulation of the Bollgard II XtendFlex cotton technology, Deltapine has announced plans to offer five new B2XF varieties for the 2015 season.

Product News

Bollgard II XtendFlex Cotton Poised for Limited Introduction

January 21, 2015

A limited introduction of Bollgard II XtendFlex cotton varieties is planned for the 2015 planting season through Deltapine and select licensees.

Latest News
Insect Control

Genome Mapping Signals Brighter Days for U.S. Cotton

December 6, 2014

At a time when growers rely increasingly more on genetic advancements in yield and fiber quality to keep cotton economically viable, cotton breeders and researchers are excited about the possibilities that genome mapping brings to variety and trait development.

Weed Control

Georgia Growers Lay the Blueprint for Pigweed Control

December 3, 2014

It makes sense for Georgia – the first state to confirm glyphosate resistant pigweed – to be one of the first places for the investment in pigweed control to begin visibly paying off.

News

Details from Summit on “Wicked” Herbicide Resistance Problem Now Available Online

October 21, 2014

Slides and a webcast of the Weed Science Society of America’s scientific summit on herbicide resistant weeds are now available for free online.

News

USDA Announces Measures to Help Farmers Diversify Weed Control Efforts

October 16, 2014

USDA has announced several new steps to help address the increase of herbicide resistant weeds in U.S. agricultural systems.

Crop Inputs

Consider Options for Fall Herbicide Applications

October 7, 2014

Growers who may be considering fall herbicide applications for anything other than Italian ryegrass may want to rethink their options.

Crop Inputs

National Summit on Herbicide Resistant Weeds Set for September 10

August 31, 2014

The Weed Science Society of America will conduct a national scientific summit on herbicide resistant weeds in Washington, D.C., on September 10, including a live webcast of the event for those unable to attend in person.

Crop Inputs

Ramping Up the Outreach for Enlist Technology

August 29, 2014

Dow AgroScience is ramping up outreach and education efforts to make sure cotton producers are ready for the introduction of the Enlist Weed Control System for cotton in 2016, pending regulatory approval.

Crop Inputs

Planting Intentions for 2015 Impact Aerial Sowing of Fall Cover Crops for Weed Control

August 26, 2014

Tennessee Extension Weed Specialist Larry Steckel says there’s a lot of interest in aerial seeding of cover crops into standing crops this fall to help with weed suppression next spring.

Crop Inputs

Zidua Herbicide Now Labeled for Residual Weed Control at Layby

July 18, 2014

BASF has issued a supplemental label for use of Zidua herbicide in post-directed layby applications for weed control in cotton.

Crop Inputs

Help Manage Pigweed with Hoods and Post-Direct Applications

July 3, 2014

Management of Palmer amaranth is possible in cotton with careful use of hooded sprayers and other post-directed herbicide applications.

Crop Inputs

Tech Centers Offer Southern Growers a Look at Enlist Weed Control System

June 27, 2014

Dow AgroSciences is more than tripling the number of field training locations this summer to demonstrate the Enlist Weed Control System and other company products.

Crop Inputs

Pigweed Management Strategies Following Mid-South Rains

June 13, 2014

Frequent flooding and hard rains throughout the upper Mid-South have made it virtually impossible for growers to spray Palmer amaranth as timely as needed.

Crop Inputs

Patience Is a Virtue in Technology Development

June 3, 2014

Companies often wait more than a decade before seeing their new research ideas in the commercial market.

Crop Inputs

New Focus on Cotton Webcasts Detail High-Yield Fertilization, Palmer Amaranth Control

May 21, 2014

New webcasts on fertilization and on management of Palmer amaranth have been added to the Focus on Cotton series from the Plant Management Network and Cotton Incorporated.

Crop Inputs

Monsanto Ramping Up Education for Roundup Ready Xtend Technology, New Dicamba Products

May 5, 2014

After a year of initial show and tell for the Roundup Ready Xtend Crop System – including Bollgard II XtendFlex for cotton – Monsanto is preparing to ramp up their educational efforts in 2014 in anticipation of deregulation for a market introduction in 2015.