Category Archives: Guest Column

Difficult weeds require strong residual herbicides

Chris Pritchett

Chris Pritchett,
Product Manager,
Corteva Agriscience,
Agriculture Division of DowDuPont, Dow AgroSciences

A cold, wet start to spring is making preplant and preemergence herbicide applications challenging to schedule this year. Soybean farmers need to control difficult weeds in a timely manner to preserve yield potential.

Marestail, waterhemp, giant ragweed and Palmer amaranth are among the most difficult weeds to control in many Midwest soybean fields. These weeds have shown resistance to multiple herbicides, including glyphosate. Using multiple modes of action in a timely manner is key for effective control throughout the season.

If your customers still have time to apply a preemergence herbicide, Sonic® herbicide is a valuable tool that offers two nonglyphosate modes of action to provide long-lasting residual control. It’s proven to deliver long-lasting, broad-spectrum control to prevent weeds from invading soybean fields.

If soybeans are already emerging in your area, FirstRate® herbicide is a flexible and economical option for preemergence and postemergence control of broadleaf weeds.

If soybeans are already emerging in your area, FirstRate® herbicide is a flexible and economical option for preemergence and postemergence control of broadleaf weeds. FirstRate can be tank-mixed or applied sequentially with glyphosate to help control common ragweed, lambsquarters and marestail. DuPont EverpreX herbicide also provides a wide application window from preplant to postemergence up to 90 days before harvest. EverpreX helps soybean farmers gain residual control of many weeds and grasses resistant to ALS, PPO and glyphosate.

Visit the retailer-exclusive resource OperationCleanFields.com to learn more about how you can help your customers fight back against high-anxiety weeds in soybean fields.

®™Trademark of The Dow Chemical Company (“Dow”) or E. I. du Pont de Nemours and Company (“DuPont”) or affiliated companies of Dow or DuPont. DuPont™ EverpreX™ herbicide, FirstRate and Sonic are not registered for sale or use in all states. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Always read and follow label directions. ©2018 Dow AgroSciences LLC

Three weed control trends to watch in 2018

Kent Bennis

Kent Bennis,
market development specialist, Dow AgroSciences

Weeds are relentless year after year, leading farmers, retailers and agronomists across the Midwest to find new ways to control difficult and herbicide-resistant weeds in corn and soybean fields.

While the weed spectrum hasn’t changed much in recent years, the available methods and level of difficulty to control these weeds has changed. We’re seeing several trends, as part of a sound herbicide program, that are helping farmers improve ROI and counter weed pressure.

To overcome challenging weeds in corn and soybeans, here are three top weed-fighting strategies to keep in mind this season.

1. Invest in multiple herbicide passes
The timing of herbicide passes is shifting. There are instances when farmers prefer to apply a residual herbicide shortly after planting rather than before. Herbicide timing largely depends on the weed spectrum and density. With increasing herbicide resistance, a two-pass program is the best way to keep weeds small throughout the season.

To control weeds early – even ahead of planting – farmers can tank-mix burndown herbicides with residual herbicides to plant into a clean field. Dow AgroSciences recently received federal registration from the U.S. Environmental Protection Agency for Elevore herbicide, powered by Arylex® active, which can be applied up to 14 days before planting in soybeans and corn. Elevore is tank-mix-compatible with commonly used burndown and residual partners, including 2,4-D and glyphosate, for thorough control of many broadleaf weeds, including marestail up to 8 inches tall.

2.  Layer residual herbicides to extend weed control
Farmers should overlap, or layer, residual herbicides to control tough weeds like Palmer amaranth and waterhemp, which germinate throughout the growing season. Farmers can use Resicore® herbicide or SureStart® II herbicide for residual control in corn and Sonic® herbicide or Surveil® herbicide for long-lasting control in soybeans.

3.  Control pigweeds early before they progress across fields
Waterhemp and Palmer amaranth continue to be driver weeds in corn and soybeans. Waterhemp is slowly taking over more acres each year, and if a farmer is in an area where it was just starting to get bad last year, it’s likely getting worse.

In soybeans, farmers can also improve control of tough weeds, including the pigweed species, by planting narrow rows of seven to 15 inches. This allows the crop to shade the row much quicker, which reduces weed germination and emergence.

For more information about customizing a weed control program for waterhemp, Palmer amaranth and marestail, visit PowerOverWeeds.com.

®™ Trademark of The Dow Chemical Company (“Dow”) or E. I. du Pont de Nemours and Company (“DuPont”) or affiliated companies of Dow or DuPont. Elevore, Resicore, Sonic, SureStart II and Surveil are not registered for sale or use in all states. Resicore and SureStart II are not available for sale, distribution or use in Nassau and Suffolk counties in the state of New York. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Arylex is a registered active ingredient. Always read and follow label directions. ©2018 Dow AgroSciences LLC

Are your customers applying the right nitrogen rate?

Eric Scherder

Eric Scherder,
Customer Technical Specialist – Western Region, 
Dow AgroSciences

A combination of three nitrogen tests is a powerful decision-making tool for farmers when evaluating nitrogen fertilizer needs. The tests provide accurate estimates of available nitrogen at various times during the season.

Each test provides farmers with the best information for making nitrogen management and application decisions. Whether farmers are applying nitrogen in fall, early spring or split, the tests help farmers manage nitrogen based on science and laboratory results instead of guesswork.

Dow AgroSciences, along with fertility experts at Iowa State University, recommend farmers employ a combination of late-fall, early spring and late-spring (pre-sidedress) soil testing. It is important to use all three tests in combination by sampling at various locations in a field to get an accurate reflection of nitrogen availability and future needs.

The three tests are:
Preplant soil nitrate test — A preplant soil nitrate test measures the amount of residual or carryover nitrate-nitrogen in the soil profile, typically sampled to a 2- to 3-foot depth in the fall or early spring. The preplant test measures the amount of nitrogen remaining from the previous crop year.

Pre-sidedress soil nitrate test — If nitrogen applications are lowered based on soil profile nitrate-N sample results, farmers should complete a pre-sidedress soil nitrate test. This test allows farmers to adjust nitrogen applications before peak growth at critical nutrient uptake stages.

Fall stalk nitrate test — After harvest, a fall stalk nitrate test provides information on the relative nitrogen program results that year. Taking fall stalk nitrate tests over a period of years can help farmers fine-tune nitrogen management. Test results are not simply to be used to adjust rate for the next year, rather longer-term evaluation.

Protect your nitrogen investment
Using a nitrogen stabilizer such as N-Serve® or Instinct® has long proven effective in reducing nitrogen loss into groundwater and surface water.

N-Serve and Instinct protect applied nitrogen by keeping nitrogen in the ammonium form longer by inhibiting the conversion process to nitrate nitrogen, which is moveable in the soil. Both products slow down the conversion so your nitrogen fertilizer investment is available when the corn plant actually needs the nitrogen later in the corn plant life cycle. Stabilizers ensure that applied nitrogen will still be there in the soil profile where a corn plant needs it and won’t end up moving lower in the soil profile out of a corn plant’s reach.

There’s no arguing that nitrogen stabilized with N-Serve and Instinct can increase yield potential. Ultimately, using a stabilizer is going to help make farmers more profitable while also being a sound approach to protect precious groundwater supplies.

To calculate your customers’ return when using Instinct or N-Serve, use the profit calculator at NitrogenMaximizers.com.

Advantages of using N-Serve® nitrogen stabilizer are clearly evident in this side-by-side comparison. Rows on the left, where N-Serve was applied, are taller, greener and healthier while rows on the right appear stunted, yellow and show firing of lower leaves — all symptoms of nitrogen deficiency.

®Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow. Instinct is not registered for sale or use in all states. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Do not fall-apply anhydrous ammonia south of Highway 16 in the state of Illinois. Always read and follow label directions. ©2017 Dow AgroSciences LLC

Enlist Duo® herbicide as a burndown inspires trust, confidence

Scott Wright

Scott Wright
Enlist field specialist
Dow AgroSciences

As with any new product, some farmers are asking questions about how Enlist Duo® herbicide works and how to use it. Several farmers in 2017 got their first experience with this technology by using it as a burndown. They found Enlist Duo was effective and gained confidence in the herbicide.

John Lindamood of Tennessee was one farmer who was interested in the system, so he purchased Enlist Duo herbicide for use in burndown. He was able to control tough weeds while they were still small. In particular, annual bluegrass was “thick as a blanket.”

Enlist Duo did a fantastic job controlling weeds in Lindamood’s field, including the pesky annual bluegrass. Now, he is very comfortable with the performance and handling of Enlist Duo, and he plans to use it postemergence on Enlist™ crops.

Farmers in other areas had similar experiences. Tyler Tietjen was among several southeastern Nebraska farmers who applied Enlist Duo as a burndown this spring. It was everything he expected.

“I want clean fields when I start,” Tietjen says. “I expect the field to be 100 percent clean. Enlist Duo got everything. The field was clean after burndown.” Tietjen says the technology works as well as he had hoped.

Enlist Duo herbicide contains two modes of action: new 2,4-D choline and glyphosate. In addition to burndown applications, it is federally registered for postemergence use on Enlist corn, Enlist soybeans and Enlist cotton in 34 states.

Many farmers have been hearing good things about the Enlist weed control system, and they gain confidence once they experience it. Seeing really is believing.

®™DOW Diamond, Enlist and Enlist Duo are trademarks of The Dow Chemical Company (“Dow”) or an affiliated company of Dow. Enlist Duo herbicide is not registered for sale or use in all states or counties. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your area. Enlist herbicides are the only 2,4-D products authorized for use in Enlist crops. Always read and follow label directions. ©2017 Dow AgroSciences LLC

A weed-free field leads to higher yield potential at harvest

Lyndsie Kaehler

Lyndsie Kaehler
U.S. corn herbicides product manager
Dow AgroSciences

September is a time for reflection as the growing season ends and you and your customers spend countless hours in the field for harvest. If your customers found themselves chasing weeds this season, now is the time to consider adjustments to next season’s weed control program.

If weeds are left to grow with, or ahead of, corn at the beginning of the season, yield potential is already decreasing. Research from Iowa State University has shown that the most competitive weeds in corn are about 3 to 4 inches tall at the V3-V4 corn growth stage, and these weeds can reduce yield by about 3 bu./A for every day they are left uncontrolled. From planting until canopy closure, it’s critical to keep fields weed-free so corn can grow without being robbed of sunlight, water and nutrients.

Across the Corn Belt, grass and broadleaf weed control continues to be a high priority. Many weeds, including waterhemp, giant ragweed, foxtail, Palmer amaranth and velvetleaf, continue to spread and develop resistance to multiple herbicides. To combat resistant weeds in cornfields, Dow AgroSciences is proud to offer multiple residual herbicide solutions with versatility and multiple modes of action to control weeds several ways.

SureStart® II herbicide and Resicore® herbicide can be used together in a program approach or separately to meet your customers’ agronomic needs. SureStart II is a proven performer applied preemergence, or at planting, and can be followed by Resicore early postemergence. This program approach provides four modes of action to control your customers’ weeds in corn, including herbicide-resistant species. Plus, farmers can add atrazine and glyphosate to the program for six unique modes of action.

As combines move through fields this fall, remind your customers that a residual herbicide with multiple modes of action can give corn a clean start against their worst weeds next season. Visit PowerOverWeeds.com or contact your Dow AgroSciences sales representative to plan a weed control program for 2018.

Clean corn rows in Illinois after a preemergence application of 2 pt. SureStart® II herbicide followed by 1.25 qt. Resicore® herbicide postemergence.

®™Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow. Resicore and SureStart II are not registered for sale or use in all states. Resicore and SureStart II are not available for sale, distribution or use in Nassau and Suffolk counties in the state of New York. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Always read and follow label directions. ©2017 Dow AgroSciences LLC

More farmers learning benefits of Enlist™ soybeans this summer

Jonathan Siebert

Jonathan Siebert
Enlist field sales leader
Dow AgroSciences

A mild winter and a wet spring may be providing weeds an ideal opportunity to get established early this growing season. These conditions also may be giving some farmers an ideal opportunity to learn about Enlist Duo® herbicide in their own fields.

This summer, seed production growers are raising Enlist soybeans under the Dow AgroSciences Field Forward program. They’re getting a first-hand look at this novel weed control technology before it is commercially available.

Like other farmers who’ve planted Enlist soybeans, they’re anticipating excellent control of even the toughest weeds. You can follow some of these soybean producers throughout the growing season on Experiencing Enlist as they apply Enlist Duo herbicide in their fields and share their experiences with this new technology.

Enlist Duo is a proprietary blend of glyphosate and 2,4-D choline. It provides excellent postemergence weed control in Enlist crops: soybeans, corn and cotton. Dow AgroSciences is prepared to launch Enlist soybeans once necessary import approvals are obtained.

Visit Experiencing Enlist to see what farmers are saying about the new technology. These timely reports will help you and your customers learn more about the Enlist weed control system. Also check out our YouTube channel or follow us on Twitter at @EnlistOnline.

Enlist soybeans

Farmers from around the Midwest are growing Enlist soybeans for seed production under the Field Forward program. See their stories on Experiencing Enlist throughout the growing season.

®™DOW Diamond, Colex-D, Enlist, Enlist Duo and the Enlist Logo are trademarks of The Dow Chemical Company (“Dow”) or an affiliated company of Dow. Enlist Duo herbicide is not registered for sale or use in all states or counties. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your area. Always read and follow label directions. ©2017 Dow AgroSciences LLC 

Stacked herbicide resistance progresses across Midwest

Dave Ruen
Field Scientist
Dow AgroSciences

For nearly two decades, herbicide-resistant weeds have swept across the Midwest. Today, more fields than ever are facing weeds with resistance to multiple modes of action. With new postemergence technologies entering the market, farmers need to remain vigilant and avoid repetitive use of one active ingredient by using residual herbicides in a program approach to control their tough weeds multiple ways.

We’re trying to manage the expansion of glyphosate-resistant weeds — marestail, waterhemp and giant ragweed, for example. There’s no question in my mind that we’ve slowed the advance of glyphosate resistance due to the resurgent use of soil-applied herbicides, such as Sonic® herbicide in soybeans.

Some weeds, such as tall waterhemp, are developing resistance to multiple modes of action, an issue farmers must keep their eyes on.

In Kansas, some tall waterhemp plants are now resistant to HPPD inhibitors, ALS inhibitors and atrazine. Meanwhile in Illinois, tall waterhemp is documented with multiple resistance to PPO inhibitors, ALS inhibitors and atrazine.

In the last few years, we’ve seen a slow expansion of herbicide-resistant weeds, particularly in the upper Midwest. It’s important that we continue to increase the use of residual herbicides and not skimp on rates.

To stop weeds from robbing yield, carefully scout soybean fields and use a targeted program approach this season. Start with a clean field by applying a broad-spectrum, preemergence herbicide that has powerful activity on the Amaranthus species, including pigweeds, waterhemps, and Palmer and Powell amaranth. With two nonglyphosate modes of action, Sonic herbicide is proven to provide 94 percent control of waterhemp and 93 percent control of Palmer amaranth.

For more information about how your customers can take control of herbicide-resistant weeds in their soybean fields, visit OperationCleanFields.com.

®Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow. Sonic is not registered for sale or use in all states. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Always read and follow label directions. ©2017 Dow AgroSciences LLC