Crops

Insect control in soybeans hinges on knowing the pest and good timing

Written by Jason Worthington on .

Pest control in soybean fields takes a more active role from growers and crop consultants than managing corn. That’s not to say scouting for corn insects is not necessary—we still have cutworms to deal with in most years. There are occasional secondary pests, and we have to be vigilant to fend off resistance to Bt traits and seed-applied insecticides. However, corn-insect management has mainly consisted of adding a pyrethroid to our pre-emerge herbicide and letting the seed treatment and the transgenic traits do the rest. At the expense of soybean yield, this attitude often carries over to soybean production. Unfortunately, if growers take this laissez-faire attitude toward pest control in soybeans, it’s likely that the soybeans will take a laissez-faire approach to yield. In the current commodity price environment, each bushel counts.

Insecticide seed treatments have become a standard operating procedure for soybean growers, and a valuable tool for early-season protection. Most commonly, these treatments are controlling below ground pests that will effect stands, along with first-generation bean leaf beetles. Bean leaf beetles not only threaten the leaves and cotyledons of soybean seedlings but can vector soybean diseases such as bean pod mottle virus. In more northern geographies where soybean aphids tend to show up earlier, seed treatments can do an excellent job of controlling early infestations. However, several caterpillar pests can still be a threat early, and later infestations of aphids and bean leaf beetles can still threaten treated soybean fields.

Late season control of insect pests in soybean production takes a much more hands-on approach. To ensure season-long control, there is no substitute for scouting. Without understanding the insect population in your field, the growth stage of the crop, and the current weather pattern, an insecticide program will not be effective.

When it comes to mid- and late-season scouting, there are a couple categories of insects to consider. The first is foliar-feeding insects and sucking insects. The second is pod-feeding insects. Foliar damage is the most noticeable plant damage and the easiest to scout for, but the least damaging. Soybean plants excel at replacing leaves if damage comes during periods of rapid vegetative growth. The most vulnerable periods are during seedling stages when insects could overwhelm small plants, and reproductive stages when vegetative growth slows. Economic thresholds at seedling and reproductive stages are around 25 percent defoliation, but can be as high 50 percent during vegetative stages.

It is important to keep these thresholds in mind when treating foliar feeding insects. A treatment for these pests can prove valuable, but may also have unintended effects. Unless you use the right product, you may increase pressure from sucking pests, specifically aphids and spider mites. Both of these pests are subject to control by beneficial insects, which are affected by insecticide treatments. The best strategy is to use products that will control both aphids and mites. Such dual control is particularly helpful in hot, dry conditions where spider mites thrive. Products like Hero which contain bifenthrin help a great deal on mites. Lorsban is a good tank mix partner with bifenthrin for mite control along with adding to aphid knockdown. Any of the neonicotinoid insecticides will provide excellent residual control of aphids.

Of course, pod-feeding insects such as podworms, stinkbugs, and even bean leaf beetles are consistently the most dangerous pests to soybeans. Little damage from these pests is needed to justify treatment, and frankly, it is rare that there is not a combination of pod-feeding insects at high enough levels to treat. Since pod feeders are present the majority of the time, applying an insecticide at pod set is a good practice.

It is still important to scout. Knowing the species of insect present is critical for good control. Caterpillars, stinkbugs, and beetles, for example, all behave differently. They are best controlled by specific products. Each pest may require different rates of insecticide for control and may or may not be affected by residual control.

To ensure proper timing and product selection, scouting for threat levels is imperative. The difficulty is scouting properly and knowing how and when to look for these pests. An extra set of eyes from a consultant in a program like MFA’s Crop-Trak can help. We’ve seen good results with Crop-Trak weekly field inspections and recommendations. Communication among this network of consultants has proven that understanding emerging threats and proactive approach to control makes an effective insect control program.

It takes more than equipment

Written by Matt Stock on .

In the past two decades, precision agriculture has seen a massive influx of technology. And the progress is still rolling. Precision is an agricultural technology that, unlike genetics or chemistry, doesn’t take a dozen years to hit the next promise.

Most advances in precision ag equipment have focused on answering one of two questions: How do I increase efficiency by reducing waste, or how do I add to the convenience of the operator? In essence, products such as automatic section control on sprayers, spreaders and planters along with automatic steering have not necessarily aided our ability to increase production outright. But, by giving us options to select the right product, at the right rate, in the right place, at the right time, they have made field operations more efficient.

But what if you want to take the next step? Variable-rate fertilizer applicators have given us the ability to implement a right-product, right-place, right-rate fertility strategy and increase productivity, but that practice is not all that new. What if we had a piece of equipment that allowed us to select the right corn hybrid or soybean variety for different parts of each field?

I recently worked on MFA’s first dual-hybrid planter. It is rolling across fields this season changing from one seed variety to another based on data cataloged for zones throughout the field.

Multi-variety planting is not an enormous challenge when it comes to equipment. Our team mounted two meters with seed-delivery hoses coming from both bulk tanks, which deliver different hybrids. The meters are electrically driven, so there is no problem with chains.

The real challenge begins with identifying where to change hybrids and why. How do you identify hybrids to best fit different areas of the field? Finally, how do you determine a plant population that is appropriate for each zone and for the hybrid that fits that zone?

To anyone in MFA’s Nutri-Track program, this concept should sound familiar; tailoring the product and amount to the need of each acre, but with seed instead of fertilizer.
Selecting the right fertilizer and rate for each acre becomes simple math for a computer when compared to past yield history and soil-test levels. But, how do you determine the right seed and population for each unique soil type and yield environment?

From the MFA precision agriculture team’s perspective, making recommendations for multi- variety planting was a challenge in selecting the right data to get the best answers.

When I started looking at the fields to be planted this year, I was lost in the data. We had more than 10 years of yield data, Veris data, elevation data, soil-test data and most importantly, firsthand experience in these fields. That may sound like a lot of information but, in my opinion, you can never have too much data.

I worked on my theories and drew different zones within these fields trying to identify what was causing yield changes in each area. But, you can look at the data all day and never get the whole story. After talking to the farmer and MFA Crop-Trak consultant, we were able to identify what drives yield in each area and get a game plan together to address problems or take advantage of each acre.

At a basic level, data can tell us where to draw a line between two field zones that differ, but experience tells us why they are different and what characteristics to look for in the variety you need for that zone. I am not a seed expert, but by interpreting the data we had collected, I was able to help our seed specialist do a better job of selecting hybrids. Our options were expanded because we didn’t need a one-size-fits-all hybrid.

Making incremental increases in yield doesn’t have to be as complicated or expensive as setting up a multi-variety planter. Maybe you just want to change the population to account for soil and fertility variability. Or, maybe you just want to make sure you aren’t limiting yield based on fertility levels. Either way, it starts with collecting the data.

The future of precision agriculture is not just equipment. It’s data. More than that, it’s interpreting data to build the insight you need to make better management decisions.

Seed-care strategy

Written by Jason Worthington on .

Looking back at the past decade, it is hard to find an area of crop protection with as many developments as seed treatments. At the start of my career, when I was treating soybean seed for a customer, I remember the only real question was whether or not to treat the seed with a fungicide. History has proven that investment pays off. In fact, more than just fungicide, a seed-applied insecticide treatment is a profitable proposition for growers. Using a fungicide/insecticide treatment commonly leads to better emergence, healthier stands, less early-season insect damage, higher yields and peace of mind for the grower. The fact that fungicide and insecticide treatments are the basis for good seed treatment packages has not changed in recent years. What has changed is the multitude of options available to growers to enhance their seed care package even further.

There are numerous options for seed treatment in today’s market—enough that when you look at all of them, it can be a little overwhelming. There are products that have entered the market to aid in the control of nematodes and Sudden Death Syndrome. Some of these products work similarly to typical seed-applied pesticides we are accustomed to, while others provide a form of biological control. In addition to pest control biologicals provide benefits to crops ranging from aiding nutrient uptake, to stimulating plant growth, to inoculation. Finally, there are several products now available for custom treated seed that may not serve an agronomic purpose, but aid in seed handling with benefits including quicker drying times, more uniform coverage and increased flowability.

It would be nice if you could add a product to the seed for every possible growing challenge you will face in a season, but there is only so much surface area to put product on a seed. So you’ll have to make informed decisions to what will work best for your situation. When making that choice, here are the four places I would start.

Start with the basics

Use fungicide, insecticide and inoculant. This standard practice should be kept in place. There has been great agronomic gain in terms of reduced re-plants, stand improvement and increased yields from these practices. Shifting away from these standards would be a step backward. For the fungicide component, make sure to use a product that will control at least these four diseases: Rhizoctonia, Pythium, Fusarium and Phytopthora.

It is also important to ensure the proper rate is used to provide control of these diseases, particularly Phytopthora.

Include a systemic insecticide that will control below-ground pests such as seed corn maggots, wireworms and grubs along with early season above-ground pests such as bean leaf beetle and early infestations of soybean aphid. Finally, inoculate your soybean seed to ensure robust and early nodulation. The symbiotic relationships with bacteria in the inoculant spurs soybean plants to produce their own nitrogen (sometimes in excess of 350 pounds per acre). That makes soybean inoculants the cheapest form of nitrogen on the market.

Evaluate your SDS and nematode risk

Among the most exciting products coming to market are those designed to control soybean cyst nematode and Sudden Death Syndrome. SCN and SDS are two of the most damaging pathogens to soybean production. SCN is estimated to have caused 118 million bushels per year of lost production on a five year average and SDS averaging 35 million bushels lost per year in that same time frame. To determine the threat of nematodes in your field, rely on prior experience from scouting and digging roots to find SCN cysts on soybean roots. You can also soil test to determine SCN presence. SCN levels will be reported on tests, but remember that levels of nematodes vary greatly across your field. SDS threats will be higher wherever nematodes are present—anything that threatens a young soybean plant increases the likelihood of SDS infection. Some of these threats include nematodes, cool soils, other diseases, extreme wet conditions and any other factors delaying growth and emergence. Of course, a field history of SDS also increases the likelihood of an infection. It is important to remember that both SDS and SCN are soil-borne and not reduced much, if any, by crop rotation.

Products to help mitigate the effects of SCN and SDS products include Illevo and Poncho Votivo from Bayer as well as Clariva and Mertect from Syngenta.

Illevo has shown excellent results in reducing the impact of SDS in years when visual symptoms are noticeable, but also in years when less noticeable root infection occurs. In addition to helping control SDS, Illevo has activity against nematodes early in the soybean’s life. For additional deterrent of SCN, Poncho Votivo can be used in conjunction with Illevo. Poncho Votivo contains a systemic insecticide in addition to a bacteria that will colonize soybean roots, providing a barrier that nematodes find undesirable. This is designed to be season-long protection.

Another form of biological nematode control is provided by Syngenta’s Clariva. Clariva is a fungus transported on the seed into the soil as a spore. When in the presence of soybean cyst nematodes, the spores will continue their life cycle infecting the SCN. The spores keep reproducing to infect other SCN, with the infections killing the nematodes. If the population of the Clariva fungus thrives, season-long reduction of SCN infection can be expected. To aid in SDS control, Mertect can be used in conjunction with Clariva. Mertect is a seed applied fungicide originally used to fight phomopsis and other seed-borne diseases. At newly registered higher use rates it has demonstrated some SDS control.

Incorporate additional biologicals

Biologicals are a historic component of soybean production. The first seed treatments in the form of nitrogen-fixing bacteria inoculants were biologicals. We now have inoculants for beneficial fungi that act as an extension of the plant’s root system. Other microbes that we can inoculate seed with can help make fixed nutrients in the soil more available. We are using biologicals to aid in nematode control. Plant hormones are used to promote more rapid growth and emergence. Signal molecules will allow nodulation or other plant relationships and processes to start earlier. Before selecting a biological product, decide your objective and make sure you are purchasing from a reputable source. Two products worth investigating mentioned in Dr. Weirich’s article in February’s Today’s Farmer are Quickroots and Cue from Monsanto BioAg. Both have shown promise in tests conducted by MFA’s agronomy team.

Address seed handling issues

As we continue to put additional crop protection products on seed, we will have concerns with seed treater cleaning, seed flowability, seed coverage, product compatibility and seed safety. MFA has added multiple products to its crop protection portfolio to address these concerns. We are in the process of evaluating products to keep seed treaters clean and running efficiently. We are also looking at products to prevent bridging in the seed tender or planter, as well as products to allow higher treatment rates when needed. These products may not be part of most pest control or growth promoting products, but they are important to producing the quality custom treated product MFA strives to provide for its seed customers.

As multiple new products enter the seed-care arena, MFA’s agronomy advisers are ready to visit about what works best for your farming operation. When you talk with them, make sure to discuss the needs of your farm—not just from a pest-management standpoint, but also from a production goal and logistical view to ensure your seed-care plan is a successful one.

Working toward the benefits of new chemistry

Written by Dr. Jason Weirich on .

After significant financial investment and research, then years of waiting, Monsanto recently received approval from China for the Round-Up Ready 2 Xtend soybean trait. This trait allows application of certain labeled dicamba as preemerge and postemerge to herbicide-tolerant soybeans. However, EPA has yet to approve the herbicide to be applied preemerge or postemerge.

Even though you won’t be able to see the herbicide in action this year, I believe it is something that you should consider for your farm. Yield potential has been increased in MFA’s MorSoy lineup over the RR2 platform. It should be no surprise that newer genetics for soybeans have been focused into the Xtend platform. We have been anticipating the release of this technology for a couple of years and the yields will speak for themselves.

Although there are several dicamba molecules on the market today, none of them have a label for over-the-top use in soybeans. You will still need to follow the product label of what is in the tank for any preplant applications of dicamba.

Even though we won’t have the herbicide portion of this technology, it’s worth discussing the benefits of the herbicide platform will bring.

When you look at the weed spectrum in Midwest fields, it is clear that broadleaves are the most problematic weed. Dicamba can provide excellent postemergence control of many glyphosate-resistant and tough broadleaves. Another advantage you might have heard about is the residual activity of dicamba. While there is residual activity, its not activity that can be given a certain efficacy timeframe. You won’t have a period of weed control to mark on your calendar. The amount of time the residual will provide control is dependent on several factors, such as soil type, organic matter and rainfall.

To have consistent weed control, you will still need the active ingredients found in products like Sonic, Authority, or Valor, among others.

Once the chemistry receives domestic regulatory approval, I believe the biggest benefit of this dicambia-based system will be in the burndown market. An attractive option will be applying a burndown with dicamba along with a residual and having no plant-back restrictions.

For those of you who do your own spraying, you have probably heard that you will no longer be able to use AMS in the tank if you are spraying the new formulations of dicamba. Several companies have been at work to make sure we have water conditioners that do their job without increasing the volatility of dicamba. What is different for formulators who want to manufacture additives or companion chemicals for Xtend and Enlist technologies is that each product has to pass a series of lab experiments to be labeled.

On the meeting circuit over the past year, I’ve herd several producers talk about these new technologies being the next silver bullet. I hate to burst their bubble, but the technology just isn’t. The best strategy for any technology, Xtend, Enlist, Roundup Ready, Liberty Link or conventional, is still to use an overlapping residual program. You’ve heard me talk about it before. The graph above from University of Missouri weed scientist Dr. Kevin Bradley gives a good visual of how it works. If you have any questions or would like to develop sound weed control options please see your local MFA or AGChoice.

Give your weed control investment a better chance

Written by MFA STAFF on .

Proper choice and use of adjuvants helps crop protectants do their job

With weed challenges from the previous growing season and new herbicide technology on the market, paying attention to adjuvants takes on new importance in 2016.

The increase in the seed bank from an odd growing season and the proliferation of herbicide-resistant weeds means that weed management for the next growing season will be crucial. If there were major weed escapes, it may take years to return the seed bank to a previously lower level. In the upcoming growing season, getting adjuvants right can give your weed control program a beneficial edge.

Adjuvants improve weed control in various ways. As new herbicide technology comes to the field, one important way adjuvants contribute to weed control success is keeping spray on target. Drift control will be a priority as dicamba and 2,4-D herbicide platforms reach fields.

Adjuvants also play an important role in the efficacy of herbicides once they hit target plants. All leaves have a waxy covering (cuticle) surrounding the outside of the leaf. It’s a biological defense mechanism for the plant. The covering reduces fungal problems by allowing water to run off the leaf and helps protect the leaf under harsh environmental conditions. A herbicides has to pass through this waxy barrier to its job. Adjuvants play a role in aiding herbicide movement into the plant. There are three types of adjuvants that work directly with herbicide chemistry: surfactants, concentrated crop oils, and fertilizer salts. The herbicide a grower uses will determine which adjuvant is recommended.

Surfactants have many different roles depending on the chemistry used. Cationic and anionic (positive and negatively charged) surfactants are great wetting agents and some cationic surfactants are pre-formulated with herbicides.

Nonionic surfactants like Astute Extra, Astute and Astutue Lite do not have a charge and can be used with a wide variety of herbicides. These are not affected by ions in hard water. Nonionic surfactants are good dispersing agents. They are soluble and stable in cold water and have low toxicity to plants and animals.

Silicone-based surfactants work even better than nonionic surfactants. They are efficient at dispersing water droplets and are humectants (humidity creating). Combining these qualities increases the amount of herbicide entering the plant in addition to reducing the time for herbicides to become rainfast. However, silicon surfactants are not compatible with herbicides that need small concentrated deposits, such as glyphosate.

Regardless of surfactant, they all share a goal—to disperse water droplets. Surfactants aid in droplet creation by breaking the surface tension of water, which allows droplets to spread out rather than bead up. This is especially important when using contact herbicides such as Cobra. Contact herbicides do not move through the plant, so coverage area is extremely important.

Concentrated crop oils and methylated seed oils like Relay, Xpond and Soy Plus enhance uptake of herbicides by penetrating the cuticle. The waxy cuticle is made up of fatty organic compounds. Because oil-based adjuvants have similar chemical properties, the oils and cuticle are chemically attracted to one another. That provides better penetration of the herbicide through the cuticle. Oils also keep herbicides in a liquid state longer, further aiding herbicide uptake.

Methylated seed oils are smaller less complicated molecules, which makes them lighter and more effective at penetrating the cuticle. Crop oils and methylated seed oils must also contain an emulsifier and require agitation to keep the oil suspended in water, preventing buildup on the water surface.

AMS “conditions” hard water (AMS Advantage and Waypoint) high in magnesium and calcium ions for herbicides, especially glyphosate, which binds to these ions reducing its effect. Adding AMS before adding glyphosate to the mix can protect the herbicides active ingredient against binding.

MFA’s line of water conditioners, including AMS Advantage, Waypoint, Overide and Impetro are good options if hardwater is a obstacle.

Of course, the pesticide label is the primary source to consider when choosing an adjuvant. Here are some things to consider when the label provides you a choice.


• If both oil concentrate (crop or vegetable oil) and non-ionic surfactant are options, consider nonionic surfactant under normal weather conditions if weeds are small clearly within label guidelines. If weeds are stressed from dry weather or more mature, their cuticle material will likely be thicker. Use oil concentrate in these conditions.
• If labeled, try to include oil concentrate to control grass weeds.
• Use nitrogen fertilizer only if it is recommended on the herbicide label.
• If your herbicide has high potential for crop injury, consider nonionic surfactant instead of oil concentrate.
• To improve crop safety, do not include oil concentrates with plant growth regulator-type herbicides (i.e., dicamba, 2,4-D, etc.)
Herbicide manufacturers research the best surfactants to use with their products. Newer herbicides tend to have labels with very specific directions for amount and type of surfactant. However, some herbicides have more general recommendations in the label.
A word of caution: adjuvants are not regulated by the EPA and therefore you may hear exagerated claims about what the products can do. Make sure you buy adjuvants from a reputable source. Here are some red flags for products that might sound too good to be true:
• It is only available on the internet.
• Any claim that includes “resistant weeds” in its purpose
• An unknown company that is located outside MFA’s market area.

If you have questions about the best adjuvant for your weed control program, contact a local MFA agronomist HERE or contact This email address is being protected from spambots. You need JavaScript enabled to view it..

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