Optimizing Applications

Sophisticated tank mixes, multiple adjuvants and surfactants — this is the future of herbicide application.

What was once an activity a trained monkey could likely complete with relative success, herbicide application has progressed into somewhat of an art form as resistant weeds challenge the skills of even the most seasoned applicators.

“You used to be able to just add anything to Roundup and — as long as something was spitting out of the nozzles — it probably worked. Now it’s all about gallons per acre and overall coverage, just making sure you are getting good coverage on the weeds,” says Tony VanOverschelde, agronomy manager, CHS Eastern Farmers, Brandon, SD.

With so many different products beyond glyphosate being introduced to the tank mix, compatibility agents are expected to continue their upward growth in sales over the next few years, according to adjuvant experts.
With so many different products beyond glyphosate being introduced to the tank mix, compatibility agents are expected to continue their upward growth in sales over the next few years, according to adjuvant experts.

Jeff Nagel, agronomist, Ceres Solutions, Terre Haute, IN, sees the issue in terms of ongoing education.

“When you get into glyphosate, you’re using systemic herbicides so you’re going to be using larger droplets,” he says. “What’s changing is where we have resistant waterhemp or Palmer amaranth, it’s all about the contact herbicides, so with those particular products we find ourselves having to reeducate some farmers and say ‘Hey, 10-12 gal./A isn’t sufficient, you need to be around 15-20 gal./A and use medium to coarse size droplets rather than just coarse to ultra-coarse.

“And coverage is the name of the game.”

Back To The Basics

Throughout nearly every walk-of-life, things typically tend to come full circle. In a world of resistant weeds, herbicide application is not spared from this fact, according to Kevin Bradley, weed scientist, University of Missouri.

“We’re trying to re-emphasize things that were done by my predecessors 50 or 60 years ago,” he says. “There are a number of researchers around the country that are going back and looking at different things, such as the effect of mow-board plowing, row spacing and soybean seeding rate — things I like to call cultural practices — it’s nothing new. We have data from decades ago that shows that these practices should be implemented with herbicide practices to get the best possible control.”

Adds VanOverschelde: “Roundup made spraying easy — now with resistance you need to pay more attention to tank mixes and adding stuff to Roundup. You’re concentrating on adjuvants and surfactants, spray tips and gallons per acre — whereas with Roundup you didn’t have to do any of that. It’s kind of what we were doing in the pre-Roundup days.”

Tank Mix Takeaways

Becoming well-versed in the various tank mixable products and their interactions with glyphosate is crucial in finding a solution to resistance, according to Nagel.

“We have a lot of (tank mix) postemergence choices in corn, and we’ve got the coming dicamba products and the pigment inhibitors, so we have tank mix partners that can help the glyphosate,” he says. “On the soybean side, especially when it comes to marestail, we don’t really have a great tank mix partner yet, and we’re getting variable performance — I call it suppression because it’s really not full control. Sometimes we’ll suppress the marestail for a while and right now it’s coming through the canopy.

“And then the adjuvant package a lot of times is different too,” Nagel continues. “You may have been adding AMS with glyphosate, but now you’re typically back to using high surfactant oil concentrates and/or a nitrogen (N) source of some sort.”

VanOverschelde agrees that the days of loading up a tank with straight glyphosate and hitting the field are mostly long gone. “We’re doing a lot of add-ins with Roundup. Rarely are we doing straight roundup on anything,” he says. “Roundup and FlexStar is one that pretty much is going on everything in our territory. In the past we were doing maybe 25% residuals and now our bean residuals are increasing. What you’re doing is just adding a couple modes of action.

“One thing with Roundup is you never really had to do planning,” VanOverschelde continues. “You just said ‘well I’ll spray it twice with Roundup’ and that’s really all the thought you put into it. Now you’ve got to plan for weed size, putting on a preemergence, the right tank mixes and so on. Planning wasn’t nearly as important as it is now.”

A Take On Tillage

Re-examining tillage practices and utilizing fall residual herbicides are additional ways a grower can regain some control over unruly fields, according to Nagel.

“We’re encouraging farmers to look at fall residual programs because you can actually do a fall herbicide program for no more, or sometimes even less dollars, than tank mixing in-crop to control marestail,” he says. “Also, I think these weeds do fairly well in reduced-tillage systems, so if you do aggressive tillage it tends to disrupt that fall growth — and you’re essentially controlling it with your tillage.”

Multiple adjuvants are also becoming a popular practice, as Precision Laboratories’ Jim Reiss, president, told us back in March.

“We’re seeing a significant increase in the number of acres that have combinations of two or three adjuvants in a single application,” says Reiss. “In the past, a lot of glyphosate acres received some type of water conditioning agent and drift control adjuvant premix. As more glyphosate acres include a companion herbicide or fungicide, that addition of a second product often drives the need for more adjuvancy to maximize performance and return on investment in the additional tank mix partner.”

“Unless we start changing our practices — as in adding more tank mixes, better planning and so on — it’s just something that’s not going to go away,” says Nagel. “Farmers, retailers — everyone just has to adjust to the situation.”

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

Trending Articles

ManagementExpert To Discuss Farmland Value, Rent At Farm Science Review
August 18, 2014
While cropland values in Ohio increased in the past two years, they have remained flat in 2014, declining in some cases, according to an Ohio State University agricultural economist. Read More
EquipmentAdvance Your Technology IQ At MAGIE
August 13, 2014
The Midwest AG Industries Exposition (August 20-21) is the place you need to be to see, study and evaluate how new advances in the equipment, operations, crop protection and fertility sectors can help your business prosper. Read More
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
StewardshipMichigan Agriculture Leaders On Toledo Water Ban: We Want To Be Part Of The Conversation
August 8, 2014
Leaders of Michigan agricultural organizations said Thursday that the government should not have a “knee-jerk reaction” based on last weekend’s water ban in Toledo due to fertilizer run-off in Lake Erie. Read More
CropLife 100BRANDT Acquires Lemon Ag Services
August 4, 2014
The acquisition of Lemon Ag fits BRANDT’s aggressive corporate strategy of providing superior agronomic advice and services for customers in central Illinois. Read More
Eric SfiligojThe Resurgence Of Crop Protection
August 4, 2014
Plenty of new offerings over the next few years should see a rebirth for the crop protection products category in terms of market share. Read More

Latest News

CropLife 100Pinnacle Acquires California-Based Retailer
August 29, 2014
Pinnacle Agriculture Holdings will acquire Kerman Ag Resources, Inc., which will operate under Pinnacle's Performance Agriculture brand. Read More
Allied Cooperative Grain Plant
ManagementArcadia Co-op To Merge With Allied Cooperative
August 28, 2014
Allied Cooperative has announced that members of Arcadia Co-op voted in favor of a merger with Allied Cooperative, paving the way for the consolidation which will be effective on December 1, 2014. Read More
InsecticidesBioinsecticide VENERATE Now Registered In California
August 27, 2014
Marrone Bio Innovations' VENERATE is a new tool to help California growers control crop-damaging insect pests, fight the development of insect resistance and reduce pesticide residues on fruits and vegetables. Read More
CropLife 100Two Iowa-Based Ag Co-ops To Merge
August 27, 2014
The Board of Directors and management of United Western Coop, Missouri Valley, IA has completed a merger with Heartland Co-op, West Des Moines, IA, effective September 1, 2014. Read More
FertilizerKoch Expands AGROTAIN Nitrogen Stabilizer Portfolio
August 26, 2014
Koch Agronomic Services, LLC has added two new innovative nitrogen stabilizers to the AGROTAIN product family – AGROTAIN ADVANCED and AGROTAIN DRI-­MAXX. Read More
Seed/BiotechDuPont To Build Two Seed Treatment Centers
August 26, 2014
DuPont has announced construction on two state-of-the-art centers dedicated to developing and testing seed treatment formulations, applications and seed handling techniques in an important step toward bringing new solutions to growers. Read More
Seed/BiotechLoveland Products Acquires A Controlling Interest In Ag…
August 26, 2014
Loveland Products, a subsidiary of Agrium , has announced the company has acquired a controlling interest in Agricen, a Dallas-area agricultural biotechnology company delivering biochemical-based products for efficient and sustainable plant nutrition. Read More
StewardshipUp Close Look At The 2014 Environmental Respect Award W…
August 25, 2014
The 2014 Environmental Respect Award winners were honored recently at the 24th annual event in Wilmington, DE. Read More
Eric SfiligojAg Science Rejection Carries Consequences
August 25, 2014
As innuendo and fear dog the regulatory process, agriculture can’t get the new tools it needs to combat world hunger. Read More
LegislationFarmers Dismayed As New Farm Bill Dumps Direct Payments
August 25, 2014
The threatened end of cash subsidies to the nation’s row crop farmers dates back through at least the last two iterations of national agriculture policy legislation. Read More
MAGIE 2014 ShowStopper
EquipmentJohn Deere Again Wins MAGIE ShowStopper Award
August 25, 2014
For the second consecutive year, John Deere was honored at the Midwest AG Industries Exposition (MAGIE) for its new R4045 sprayer. Read More
CropLife 100GROWMARK CEO To Retire
August 22, 2014
GROWMARK chief executive officer Jeff Solberg has announced his retirement effective September 15, 2014. Read More
InsecticidesDuPont’s Prevathon Approved For Dry Beans
August 22, 2014
DuPont Prevathon insect control powered by Rynaxypyr has received EPA registration for foliar use on dry bean crops, including dried shelled peas and beans. Read More
ManagementNCGA DuPont New Leaders Program Enters Sophmore Season
August 20, 2014
The National Corn Growers Association and DuPont are pleased to announce the second year of the NCGA DuPont New Leaders Program. Read More
FungicidesVerdesian Links Up With Mitsui, Hokusan
August 20, 2014
Mitsui Chemicals Agro, Inc., and Hokusan Co., announced the signing of an exclusive licensing agreement allowing Verdesian Life Sciences global access to its patented technology for suppressing mycotoxin contamination in wheat and barley. Read More
SprayersUniversity Of Illinois Introduces New Spray App
August 18, 2014
University of Illinois Extension has released a new smartphone app for making sprayer-related calculations. Pesticide Spray Calculator, or Spray Calc, Read More
Crop InputsSyngenta Names New Manager Of Federal Government Relati…
August 18, 2014
Laura Wood Peterson has joined Syngenta as manager of federal government relations, based in Washington, DC. Read More
ManagementExpert To Discuss Farmland Value, Rent At Farm Science …
August 18, 2014
While cropland values in Ohio increased in the past two years, they have remained flat in 2014, declining in some cases, according to an Ohio State University agricultural economist. Read More