Weed Management Program Profiles

Here’s quick look at weed control strategies and their cost.

Over the past 20 years many growers — and perhaps dealers — have been relieved to leave behind the days of managing multiple products and approaches for weed control. Glyphosate, and later, glyphosate-resistant seed, made everyone’s job easier. But the industry is now returning to the host of crop protection tools developed over decades — though this time with an eye toward more careful planning.

To that end, chemical manufacturers, weed scientists and other stakeholders in agriculture have been working to engineer new, sometimes more complex herbicide programs. The goal is to both kill weeds and preserve effective products. Dealers are seeking out the best strategies, and the effort takes resources and patience. One proof of the challenge lies in the fact that Midwest universities’ herbicide guides include bountiful pages and charts covering current products and their uses.

Dealers we talked with suggested it can be difficult to nail down a typical cost per acre because so many options are available. Kevin Mainord, sales and marketing director with MRM Ag Services, East Prairie, MO, puts the range at $18 to $50 depending on past weed pressure and the level of control desired by growers. Plans incorporate products with varied modes of action throughout a season.

Current Approach To Corn

In many cases, dealers recommend a program start with fall burndown products to prevent winter annuals from germinating, says Shane Eck, location manager at Mid Kansas Cooperative (MKC), Lindsborg, KS. He also suggests a preplant/preemergence application come spring to kill existing weeds as well as prevent other weeds from germinating.

A postemergence application would be next — prior to canopy — to kill existing weeds. A key with post applications is timing. “It’s important to follow the label and not spray weeds that are larger than the recommended height,” points out Eck. Larger, more mature weeds have a better chance of surviving off-label applications. Specifically, Midwest extension weed specialists say products should go on before weeds exceed two to four inches to avoid excessive crop competition.

Hitting weeds when they’re small with the right rate is also tantamount. While a lower rate may actually take out virtually all of a particular field’s weeds, the ones that do survive will reproduce and can contribute to the development of resistant populations.

Mainord offered a quick summary of his company’s corn programs: Preemergence product applied behind the planter (“most premix products work”), then an early postemergence application of compounds such as dicamba/diflufenzopyr premix and glyphosate.

Jeff Consbruck, seed lead, CPI Coop, Hastings, NE, says that “in our corn programs we really encourage a two-pass approach. We try and use multiple modes of action and get the first pass on as early as the
weather permits.”

In fact, the efficacy of a one-pass program made at 1) preemergence with a residual herbicide or 2) postemergence with a tank mix of glyphosate and a residual product — raises doubts for Micheal Owen, weed science extension specialist with Iowa State University. “Regardless of what some advertising suggests, no herbicide treatment will provide full season control consistently, and more importantly, meet grower expectations,” he has commented in the school’s ICM newsletter. An appropriate expectation for a soil-applied herbicide treatment would be six to eight weeks of effective control, he explains. If rates are reduced expect less weed control.

Plans For Soybeans

Here again, it’s vital to start clean, said many of the dealers contacted. As with corn, MKC’s Eck suggests a fall burndown with preemergence control to prevent winter annuals from germinating. Then would come a spring burndown product with residual action. “Some growers like to use a preemergence chemical preplant, while others prefer to use a preemergence application in-crop,” says Eck. “An in-crop application is generally planned prior to canopy.”

Mainord suggests a preplant incorporated product on grass — or for just broadleaf weeds, depending on specific pressure. He also says growers can do an early postemergence application with both a contact and a residual product in the tank.

Consbruck would say soybeans are where his clients are having the most trouble these days. “Starting with a pre is a must anymore, as weeds in our area such as marestail, waterhemp and Palmer amaranth are getting very hard to control.

“Timing is our biggest challenge due to weather conditions and the fact that we are in the middle of applying our corn preemergence products and fertilizer at this time as well,” he adds. “Getting the pre on early ­— such as Enlite, Verdict, Prefix or Sonic — and then coming back with a tank mix of Roundup and another mode of action seems to be what is working in our area.”

Fortunately, research has yielded many non-chemical strategies in the weed wars. For instance, University of Illinois and USDA work has shown that several good cultural practices help: adequate seedbed preparation, adequate fertilization, crop rotation, planting on the proper date, using optimal row widths and seeding at the rate needed for optimal stands.

Their research also confirms that planting in relatively warm soil can help the crop emerge quickly and better compete with weeds. In fact, both corn and soybeans usually compete quite well with most weeds that begin growing beyond the first three to five weeks after planting — so good weed control during that early phase is extremely important. In addition, narrow rows help the crop compete better with weeds. Experts say that if herbicides alone cannot give adequate control, then growers should keep rows wide enough for cultivation.

Topics:

Leave a Reply

Weed Resistance Stories
Weed ResistanceWeeds: The Fearsome Five
October 1, 2013
Although there are currently dozens of weeds that show some kind of resistance to herbicides, these five are the most troublesome. Read More
Weed ResistanceWeed Management Program Profiles
October 1, 2013
Here’s quick look at weed control strategies and their cost. Read More
Weed ResistanceRecognizing Resistance
October 1, 2013
Recognizing the presence of herbicide-resistant weeds and formulating a total management plan is becoming more important than ever. Read More
Mature Waterhemp in Corn
Weed ResistanceWhen Weed Control Goes Wrong
October 1, 2013
Beyond the possibility of resistance developing, ineffective control exacts cost to growers in lost yield. Read More
Top 100 Articles
CropLife 100BRANDT Commemorates National Ag Day
March 20, 2015
The Illinois agriculture community gathered at BRANDT global headquarters on March 18 to celebrate National Ag Day behind this year's theme Sustaining Future Generations. Read More
Wheat Growers, North Central Farmers Elevator Pursue Merger
CropLife 100Wheat Growers, North Central Farmers Elevator Pursue Merger
March 3, 2015
Two CropLife 100 retailers — South Dakota Wheat Growers (ranked No. 11) and North Central Farmers Elevator (No. 19) — have entered into a Letter of Intent to unify the two companies into a newly named cooperative. Read More
Growmark Group
CropLife 100GROWMARK In 2015: Back, To The Future
March 2, 2015
The nation’s third largest ag retail organization is simultaneously moving forward while remembering its past. Read More
CropLife 100Pinnacle Expands Sanders Brand In The South
February 27, 2015
Pinnacle has acquired Hopkins Seed and Chemical in Qulin, MO, which expands the company's Sanders brand to nine Southern states. Read More
CropLife 100Pinnacle Launches New Providence Agriculture Location In Indiana
February 27, 2015
Pinnacle Agriculture Holdings — ranked No. 6 on the CropLife 100 — has established a new retail location in New Castle, IN, which will operate as part of Pinnacle's Providence Agriculture brand. Read More
Carl Casale of CHS
CropLife 100Cooperative CHS Returns $518 Million To Owners
February 23, 2015
The 2015 cash return to owners is based on CHS net income of $1.1 billion, the company's second highest on record. Read More
Latest News
FungicidesSyngenta Suing Willowood Over Azoxystrobin Fungicide
March 27, 2015
Syngenta announced today that it has sued agrochemical maker Willowood, LLC., for patent and copyright infringement, as well as unfair Read More
ManagementRetail Week: The Future Of Mycogen Seeds; The 4Rs At Na…
March 27, 2015
Editors Eric Sfiligoj and Matt Hopkins discuss recent trips, including a look at the future of Mycogen Seeds at Dow Read More
Eric SfiligojMonsanto Hears The WHO
March 27, 2015
Another challenge to the safety of glyphosate, and the responses from supporters and opponents, calls to mind a classic Dr. Seuss story. Read More
Industry NewsMonty’s Plant Food Expands Sales Team
March 27, 2015
Monty’s Plant Food Company, a leader in natural soil enhancement and  plant fertility products, has hired Andrew Bullock as a Read More
Crop InputsSyngenta Louisiana Plant Poised For 2015 Production
March 26, 2015
As the 2015 planting season gets underway, growers across the country will need crop protection products to combat pests and Read More
Lake Erie Nutrient Stewardship
LegislationOhio Lawmakers Finalize Phosphorus Restrictions
March 25, 2015
State lawmakers on Wednesday finalized new rules designed to curb toxic algal blooms on Lake Erie, calling the regulations a major step forward in addressing the problem. Read More
Spreaders17 Fertilizer Spreaders For 2015
March 25, 2015
Manufacturers shoot for versatility and accuracy in this year's crop of fertilizer spreaders. Read More
Industry NewsMonty’s Hires Mid-South Product Consultant
March 25, 2015
Monty's Plant Food Co. has hired Matt Woodring as a Product Consultant for portions of Central Kentucky and Tennessee.    Read More
StewardshipMapShots Integrates With DriftWatch
March 23, 2015
Growers and agricultural providers using AgStudio FARM and AgStudio PRO can now view vital information about specialty crops and apiaries through a recent integration with the DriftWatch Specialty Crop Site Registry from FieldWatch, Inc. Read More
Crop InputsWorld Health Organization Report Contradicts Scientific…
March 23, 2015
A new report from the World Health Organization has classified glyphosate with a “2A” rating as a probable carcinogen, a Read More
Eric SfiligojSeed Treatment Stays Necessary
March 20, 2015
Grower-customers looking to scale back spending in 2015 won’t consider seed treatment, say experts. Read More
HerbicidesMARCH MADNESS: Industry Rallies Around Glyphosate Safet…
March 20, 2015
A newly published report from the International Agency for Research on Cancer (IARC) classifies the herbicide glyphosate as a "2A-rated possible carcinogen" and the ag industry responds by circling the wagons. Read More
ManagementRetail Week: Precision survey, a technology acquisition…
March 20, 2015
Editors Paul Schrimpf and Eric Sflilgoj discuss recent travel, the upcoming precision adoption survey, and an unusual sighting at a Read More
CropLife 100BRANDT Commemorates National Ag Day
March 20, 2015
The Illinois agriculture community gathered at BRANDT global headquarters on March 18 to celebrate National Ag Day behind this year's theme Sustaining Future Generations. Read More
Crop InputsBioSafe Launching TerraGrow Soil Inoculant
March 20, 2015
TerraGrow is a blend of beneficial bacterial and fungal spores and nutrients carefully designed to promote healthier soil and crops. Read More
Winter Wheat
AdjuvantsMax Systems Debuts New Adjuvant NanoRevolution 2.0
March 18, 2015
Added to a tank mix of glyphosate at the conservative rate of two to four ounces per acre, NanoRevolution 2.0 has proven effective in killing resistant weed species that had already had up to two applications of the leading glyphosate product. Read More
Photo credit: United Soybean Board/the Soybean Checkoff
Seed/BiotechAgnition Launches Microbial Catalyst Seed Treatment
March 18, 2015
Agnition it has launched Commence for Soybeans, a microbial catalyst seed treatment for soybeans that stimulates microbial activity for healthier soil and a superior growth environment. Read More
4R Certified, Nutrient Stewardship Council,
StewardshipTyler Grain & Fertilizer Now 4R Certified
March 18, 2015
The 4R Nutrient Stewardship Certification Program has announced Tyler Grain & Fertilizer Co. in Smithville, OH, has been added to Read More