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

Matt Hopkins15 Best New Agriculture Apps Worth Downloading In 2014
December 16, 2013
These latest agriculture apps are sure to help ag professionals do their jobs more efficiently in 2014 and beyond. Read More
Seed/BiotechMonsanto Offers New Support For Ferguson, Area Communities
October 8, 2014
Monsanto Co. has committed $1 million in new support for several collaborative efforts in Ferguson, MO, and surrounding communities in North St. Louis County. Read More
Seed/BiotechUnapproved Genetically Modified Wheat Found In Montana
October 3, 2014
USDA reports that one year after discovery of Monsanto's unapproved wheat in a single Oregon field disrupted U.S. wheat export sales, the GMO wheat has again been found in Montana. Read More
Equipment2014 Product Of The Year Voting
September 19, 2014
Many new products were introduced to the ag retail marketplace this year. From this group, CropLife IRON and its consulting partners have selected five finalists for the Product of the Year award. Please cast your vote today to help us determine the winner. Read More
FertilizerFall Fertility 2014: Forecasting Fertilizer Use
September 7, 2014
Great crops this year have tapped the soil, and fall work is definitely called for, but how challenging will that get? Read More
CropLife 100CHS To Build $3 Billion Fertilizer Plant In North Dakota
September 5, 2014
The fertilizer plant in Spiritwood will be the single largest investment in CHS history, as well as the single largest private investment project ever undertaken in North Dakota. Read More

Latest News

Seed/BiotechEPA Approves Dow’s Enlist Duo Herbicide
October 15, 2014
The Enlist Weed Control System, breakthrough technology to fight resistant and tough weeds, has received the long-awaited green light from federal regulatory authorities. Read More
MicronutrientsGypsum On Farms Could Help Keep Water Clean, Not Green
October 14, 2014
Gypsum, which has roots in the past as a farm soil treatment, also may have a bright future, and not just as a booster of crops but also as a protector of water. Read More
Photo credit: The United Soybean Board/The Soybean Checkoff.
Crop InputsVerdesian Grows Sales Staff
October 14, 2014
The new account managers will drive sales growth and support relationships with key customers in the plant nutrition and seed treatment and inoculants product categories. Read More
WebinarsUpcoming Webinars
October 14, 2014
Register for one of our upcoming Webinars or access our archive of past Webinars to view recordings of presentations that may be of interest to you. Read More
CropLife 100The Andersons Purchases Six Grain Elevators, Four Agron…
October 14, 2014
The Andersons has acquired Auburn Bean and Grain of Auburn, MI, which will increase the storage capacity of its Grain Group by about 13%. Read More
StewardshipThree Ohio Ag Retailers Honored With 4R Certification
October 13, 2014
The 4R Nutrient Stewardship Certification Program has announced its first three agriculture nutrient service providers to achieve certified status. Read More
Eric SfiligojEntering Agriculture’s New Phase
October 13, 2014
The market’s giddy ride the past few years might be coming to an end in 2015, warns one industry insider. Read More
Eric SfiligojWar And Green Peace
October 11, 2014
A one-time member of Green Peace recently explained why he left the organization after 15 years. Read More
StewardshipCover Crops Add To Farm Sustainability
October 10, 2014
Farmers nationwide find cover crops to be a tool that helps groundwater, prevents erosion, builds soil quality and complements existing best management practices. Read More
EquipmentMeeting Changing Liquid Storage Needs
October 10, 2014
Tank and containment choices are expanding with shifts in farming practices and the economy. Read More
StewardshipEDF Launches Initiative To Reduce Fertilizer Pollution …
October 9, 2014
The effort will engage farmers and businesses throughout the supply chain to transform the way fertilizer-dependent grain crops are grown and sourced. Read More
ManagementMACA 2014: The State Of The Agricultural Industry, And …
October 9, 2014
The trade association’s annual gathering featured speakers from across agriculture and beyond. Read More
FertilizerASA: Drainage Tiles A Big Part Of Phosphorus Problem
October 8, 2014
A pair of studies published in the Journal of Environmental Quality today indicate that the buried network of drainage pipes known as the tile system can carry away as much phosphorus as surface runoff. Read More
FertilizerCompass Minerals Debuts Phosphorus Blend For 2015
October 8, 2014
The makers of Wolf Trax DDP Nutrients designed Nu-Trax P+ with the CropStart Nutrient Package, a blend of phosphorus (25%), zinc (20%), manganese (5%) and nitrogen (4%). Read More
ManagementIndiana Certified Crop Advisor Of The Year Nominations …
October 8, 2014
Indiana Farm Bureau and the Indiana Certified Crop Adviser Program are seeking nominations for the Indiana Certified Crop Adviser of the Year Award. Read More
Seed/BiotechMonsanto Offers New Support For Ferguson, Area Communit…
October 8, 2014
Monsanto Co. has committed $1 million in new support for several collaborative efforts in Ferguson, MO, and surrounding communities in North St. Louis County. Read More
Precision AgGoogle Glass: New Tool For Ag
October 8, 2014
New wearable smart technologies such as Google Glass show potential to greatly impact how we accomplish the business of feeding the world. Read More
FertilizerJ. R. Simplot To Build New Ammonia Plant In Rock Spring…
October 7, 2014
The new plant will supply both the Rock Springs, WY, and Pocatello, ID, phosphate fertilizer production locations while having the capacity to meet the company’s next phase of anticipated phosphate expansion plans at Rock Springs. Read More