Controlling Marestail After Crop Emergence

Glyphosate-Resistant MarestailOver the past several days, growers have increasingly been looking for options to control marestail (horseweed) after crop emergence, said University of Illinois associate professor of weed sciences Aaron Hager.

“Many have reported poor marestail control from herbicides applied prior to planting (primarily no-till soybean), especially when these burndown applications contained only glyphosate or glyphosate and 2,4-D,” Hager said. “The increasing frequency of glyphosate-resistant marestail populations, the rush to plant whenever field conditions were conducive, and the less-than-ideal environmental conditions when many burndown applications were made, have contributed to a challenging situation for which a good solution might not be available.”

Hager added that while several herbicides can control emerged marestail plants that are less than 6 inches tall, few herbicides will control plants that are 12 inches or taller.

“The majority of Illinois corn acres receive one or more tillage operations prior to planting, and these tillage operations generally control emerged marestail. However, marestail might be a problem in corn acres planted with limited or no preplant tillage,” he explained. “Growth regulator herbicides, such as dicamba and 2,4-D, can provide control or suppression of emerged marestail. Some acetolactate synthase (ALS)-inhibiting herbicides also have activity against marestail, and control is sometimes improved when — if allowed by label — these herbicides are tank-mixed with dicamba or 2,4-D.”

Another option for control is glufosinate applied alone or with atrazine in glufosinate-resistant corn hybrids. “Keep in mind that if glufosinate was applied as a burndown treatment prior to corn planting, no in-crop applications of glufosinate can be made,” he cautioned.

Foliar-applied hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors combined with atrazine are other options that can provide control/suppression of emerged marestail less than about 6 inches tall, Hager added.

“Marestail that survived a burndown herbicide in no-till soybean can be very difficult to control after soybean have emerged. Cloransulam or chlorimuron-containing products can be applied postemergence to suppress or control emerged marestail,” he said. “These products should be applied after the first soybean trifoliolate has expanded and before marestail height exceeds 6 inches.

“These products can be tank-mixed with glyphosate for postemergence applications in glyphosate-resistant soybean. Glyphosate is an option for control of glyphosate-sensitive biotypes and glufosinate is an effective option when used in glufosinate-resistant (Liberty Link) soybean varieties,” he explained. “Foliar-applied protoporphyrinogen oxidase (PPO)-inhibiting herbicides will not control emerged marestail.”

Hager added that another option to consider is to physically remove the surviving plants with a hoe, weed hook, or by pulling them from the soil.

“Before summarily dismissing this as a viable option, remember that marestail plants can be very competitive with soybean and can produce around 200,000 seeds per plant that are easily dispersed long distances by wind,” he said. “A few plants that reach maturity this year can produce a sufficient amount of seed to infest an entire field within only a couple of seasons. Removing surviving marestail plants before they produce seed could save a great deal of time, money, and consternation in future seasons.”

Topics:

Leave a Reply

Herbicides Stories

glyphosate
Crop InputsWHO: Glyphosate ‘Unlikely’ To Cause Cancer
May 16, 2016
Via Reuters.com reporter Kate Kelland: The weed-killing pesticide glyphosate, made by Monsanto and widely used in agriculture and by gardeners, Read More
dicamba, Roundup Ready 2 Xtend
Crop InputsASA: No Dicamba On Roundup Ready 2 Xtend In 2016
May 16, 2016
While Roundup Ready 2 Xtend (RR2X) are tolerant to dicamba and glyphosate herbicides, no dicamba herbicides will be approved for Read More
CPP, glyphosate, dicamba, atrazine,
Crop InputsReport: Congress Pressing EPA On Glyphosate Review Handling
May 16, 2016
Via Reuters.com reporter P.J. Huffstutter: U.S. lawmakers have asked EPA to explain why it published – and then withdrew – Read More
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
Trending Articles
Eric SfiligojPity The Monsanto Haters
May 23, 2016
An old saying goes thus: “Be careful what you wish for. You just might get it.” Given current events, there Read More
Monsanto Luling Plant
Crop InputsReport: Bayer Eyeing Monsanto For Possible Mega-Merger
May 16, 2016
Bayer AG is exploring a potential bid for U.S. competitor Monsanto Co. in a deal that would create the world’s Read More
Aerial Drone
Precision AgA Deeper Dive Into The Future Of Precision Ag
May 9, 2016
For about two decades now, through the good and the bad times, the ups and the downs inherent in agriculture, Read More
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
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
Latest News
ManagementWashington Visit and Bayer/Monsanto Deal Update
May 26, 2016
Editors Paul Schrimpf and Eric Sfiligoj discusses a recent trip to DC and the latest news on the proposed pairing Read More
Fertilizer closeup in hand
Industry NewsVerdesian: Striking A Balance Between Yield & ROI
May 26, 2016
Finely tuned nutrient management plans are helping farmers throughout the U.S. improve nutrient use efficiency, increase return on investment (ROI) Read More
Crop InputsLand O’Lakes Announces Minnesota Water Quality Pa…
May 25, 2016
Governor Mark Dayton and Land O’Lakes, Inc. President and CEO Chris Policinski today announced a new public-private partnership to protect Read More
Soybean Plant closeup
Industry NewsMonsanto Rejects Bayer Bid; Open To More Talks
May 25, 2016
Monsanto Co, the world’s largest seed company, turned down Bayer AG’s $62 billion acquisition bid as “incomplete and financially inadequate” Read More
Corn close up
Crop InputsArysta LifeScience Establishes Global Headquarters In R…
May 25, 2016
Arysta LifeScience has announced plans to relocate its global headquarters from West Palm Beach, FL, to Cary, NC, over the Read More
fertilizer blending and storage, Top 100
BlendersCHS Dakota Expansion Features AGCO’s GSI InterSys…
May 25, 2016
The continued growth of precision agriculture has increased farmer use of customized fertilizer blends best-suited for their soil conditions. Several Read More
ManagementAgriculture 3.5: A Bumpy Road Ahead
May 24, 2016
You may have read my article a few years ago on Agriculture 3.0, which is a term I coined to Read More
Topcon’s X30 display with CropSpec sensors
EquipmentGPS Autosteer Systems: Product Updates From Precision A…
May 24, 2016
Throughout 2015 GPS Steering solutions continued to evolve from what was once an after-market add on, to today’s cab where Read More
Trimble TMX-2050 In-Cab Display
Eric SfiligojThe Precision Ag Revolution Continues
May 24, 2016
It’s funny how much “the first time” tends to mean to someone as they get older. I sometimes can’t recall Read More
Eric Wintemute, AMVAC
Precision AgAMVAC Ups The Ante With New Precision Ag Technology
May 24, 2016
A potentially industry-changing at-plant soil treatment system from American Vanguard Corp., or AMVAC, is coming soon to large growers in Read More
Dry and Liquid Plant
CropLife 100CropLife 100 Map
May 24, 2016
The new CropLife 100 map shows the locations of each of the headquarters of the 2015 CropLife 100 retailers. The interactive Read More
Southern States Cooperative
Corn Field
Industry NewsTiger-Sul Names Veteran Account Manager To Lead Central…
May 23, 2016
With the continuing growth of the sulphur bentonite and precision crop nutrient industry, global agriculture firm H.J. Baker has announced that Read More
Bayer sign
Industry NewsReuters: Bayer Defies Critics With $62 Billion Monsanto…
May 23, 2016
German drugs and crop chemicals group Bayer has offered to buy U.S. seeds company Monsanto for $62 billion in cash, Read More
Eric SfiligojPity The Monsanto Haters
May 23, 2016
An old saying goes thus: “Be careful what you wish for. You just might get it.” Given current events, there Read More
Industry NewsCompass Minerals Hires Industry Veteran To Lead Plant N…
May 19, 2016
Compass Minerals has hired plant nutrition industry veteran Vatren Jurin to steer the company’s portfolio expansion into specialty liquid micronutrient Read More
ASMARK Retailers LIVE! Tour 2016 Group shot The Andersons
CropLife 100The Andersons Rejects Unsolicited Proposal From HC2
May 19, 2016
The Andersons, Inc. has announced that its Board of Directors has rejected two non-binding, highly conditional, unsolicited proposals from HC2 Read More
glyphosate
Crop InputsWHO: Glyphosate ‘Unlikely’ To Cause Cancer
May 16, 2016
Via Reuters.com reporter Kate Kelland: The weed-killing pesticide glyphosate, made by Monsanto and widely used in agriculture and by gardeners, Read More