Crops

Manage fields to influence infiltration

Written by Matt Hill on .

Water infiltration, the process by which water on the ground surface enters the soil, is a critical component of the water cycle. The goal is to keep infiltration rates as high as possible. Reduced infiltration has negative effects, some catastrophic.

Many factors influence infiltration, and it is important to remember that a “good” or “bad” measurement of any factor independent from the others does not indicate what the infiltration rate will be. They all work together to form a composite measurement that determines how well water is able to enter the soil profile at any given location. We can’t control some of the factors, but it’s good to know how they influence infiltration rates so we can consider them when choosing management strategies.

We know that infiltration is reduced in cities with every new building, each square foot of parking lot and every concrete drainage ditch. The drastic decrease of infiltration in urban areas leads to local drought, severe flash flooding and nearby streams full of whatever pollutant washed off the streets.

Inadequate water infiltration isn’t limited to the concrete jungles. Many crop fields and pastures have reduced infiltration, too. While the evidence isn’t as dramatic as cars floating down a street, it’s important to understand that reduced infiltration can result in increased erosion, ponding and drowned-out spots, decreased water quality in streams and ponds and, most importantly, inadequate soil moisture for optimum crop growth.

Water relies on voids in the soil to enter and move through the profile. The size and amount of voids are affected by factors such as soil particle size, amount of aggregation, earthworm tunnels and root channels. Frequent tillage is the most common reason infiltration is decreased. Every time the soil is tilled, the pore spaces are broken down and filled in, creating less space for water to enter.

We also need to be able to slow water down enough for it to infiltrate. If water is rushing across the slope in a field or pasture, most of it is not going to get into the soil, no matter how good the soil structure. Places with varied topography or little residue are at risk for poor infiltration just as they are for erosion.

Keeping tillage to a minimum is the primary management strategy to increase infiltration. That will allow for better soil aggregation, less potential for compaction and more abundant soil biology. Keeping crop residue on the surface and using cover crops will impede water flow and give it more time to infiltrate.

MFA Crop-Trak consultants will work with you to identify the best management strategies for your operation, including how to maximize infiltration and crop yields. Your local NRCS office is also a great place to get more information about the importance of infiltration and cost-share programs that are available to help pay for practices to address infiltration concerns on your farm.  

This complex topic is difficult to describe without illustration. The University of Missouri has conducted research about water infiltration and drought mitigation. A video discussing the results of that study is available on YouTube at https://youtu.be/o_d18qX7VFk. NRCS staff have rainfall simulators that are another great demonstration of how different management strategies affect infiltration. If you haven’t seen one, search for “rainfall simulators” online to find several videos showing those demonstrations.

Keeping it under wraps

Written by Marc Epp on .

Forages are at their best when first cut, but quality begins to deteriorate quickly between harvest and storage. An alternative to putting up dry hay is baleage, also called haylage or round baled silage. With baleage, forage is baled and wrapped in plastic at high moisture, up to 65 percent. Inside the plastic, the forage is ensiled and quality is preserved. This storage method minimizes weather risks that can affect hay quality while drying in the field. For regions that receive frequent spring rain and/or high humidity, the method offers producers flexibility in the field and allows less time between cutting and storage.

When it comes to harvesting and handling, putting up high-quality baleage is the same as conventional dry hay. Its quality is a function of forage maturity when cut and how it’s subsequently handled during baling and storage. If the bales are too wet or dry and spoilage occurs, there can be significant losses in value. As long as baleage is done correctly, however, there are decreased harvest losses and increased quality compared to the same-quality dry hay.

Here are some tips for harvesting, wrapping and feeding the highest-quality baleage:

Cutting and prepping:

  • Cut forage in late-boot to early-head stage to maximize sugars and the fermentation process.
  • Cut after the dew has dried from the standing forage. Using the moisture in the plant—not on the outside—is crucial.  
  • Set the mower to lay the forage as wide as possible to enhance even drying. Forage containing less than 40-percent moisture or much above 65 percent should not be baled for silage to avoid excessive molding or spoilage.
  • Rows should not be tedded. This will alter the straight orientation of the stems, which will reduce the efficiency of a tight bale.

Baling:

  • The key is to eliminate as much oxygen as possible. Making a tight bale will help do this.
  • Research has shown that exceptional baleage can be made without the use of additives. This is true even when ensiling legume crops that have more difficulty reaching the pH range of stabilized fermentation. However, inoculating with Lactobacillus buchneri strains can accelerate the rate of fermentation and improve stability of the silage during feeding. This is particularly important if the baleage is to be fed during the summer or in warm climates.
  • Pre-cutters in the baler will increase bale density and improve fermentation.
  • When using in-line tube wrappers, create uniform bale sizes as much as possible to eliminate unevenness when stacked against each other. Irregularity of the tubes may expose more oxygen to the bale.
  • Wrapping bales at the proper moisture content (45-60 percent) will help minimize the risk of botulinum toxicosis, caused by a potent bacterium in the environment. The spores remain dormant until exposed to anaerobic conditions and the right nutrients, which can cause them to germinate, grow and release toxins.

Storing:

  • Ideally, bales should be wrapped immediately after baling, but research has shown waiting up to 12 hours has minimal effect on forage quality. Wrap that is typically 1 mil thick, when overlapped, should give coverage thickness of 4-6 mil of plastic and 50- to 55-percent stretch. Wrap in dry weather for plastic to stick.
  • Store bales on level ground free of rocks or other sharp objects that may puncture the plastic. Orient the bales to minimize constant direct sunlight in a single area, such as in a north/south line. This will reduce sweating and deterioration of the plastic. Periodically check the bales for tears or holes and fix right away. Use tape made for the plastic, not duct tape.

Feeding:

  • Some mold will form around the edges. This is usually just at the surface, and animals will eat around it. It will not significantly harm the animal if some is eaten.
  • For bales to appropriately ferment, it is best to wait six to eight weeks before beginning to feed them.
  • If forages are baled at more than 60-percent moisture, feed these first as the shelf life is only about three months. At 30- to 40-percent moisture levels, feed value declines after six months. In general, forages baled at 40- to 60-percent moisture will maintain feed value for about 12 months as long as the plastic is intact. However, even when baled at the appropriate moisture level and the plastic has a minimal amount of holes, it is best to feed baleage within nine months.

Manage diseases with multi-faceted approach

Written by Jason Worthington on .

When considering seed treatments, we usually think first about their necessity and then what products will work for a particular field. We don’t often think about stewardship of these products. I am guilty of it as well. When discussing seed treatments, I usually talk about their benefits and product selection with a mind toward disease control. Stewardship is a second thought.  

However, when we look at available seed treatment products compared to the spectrum of seedling diseases, we quickly realize the importance of stewardship. There are few effective modes of actions available. To conserve seed treatments as a crop protection tool, they must be used in conjunction with sound cultural practices.

In this part of the world, when we think about resistance, herbicides are our first concern. But resistance management should be considered when dealing with any pest, including seedling diseases. When you break down our driver diseases and effective sites of action, the need for resistance management becomes much more apparent. There are essentially six different sites of action, or classes of fungicides, used in seed treatments today, compared to 19 classes of herbicides.

But, just as not all herbicides are effective on all weeds, not all seed treatment fungicides are effective on all seed-borne or seedling pathogens. When we look at our driver diseases used to make seed treatment decisions, they fall into two classes: water molds (phytopthora and pythium) and true fungi (rhizoctonia and fusarium). When we look at these groups separately, there are only three modes of action and four sites of action to control true fungi and a mere two sites of action effective against water molds. With so few choices coupled with logistical difficulties of handling multiple seed treatments, rotation of fungicides becomes complicated to implement as a resistance management strategy.

So what are our options? First, seed treatments cannot be our only defense against disease. Just because a fungicide is applied to the seed does not mean we can ignore other factors that favor disease development. Remember the components of the disease triangle from biology class. To have a disease, we need three things: a host, a pathogen and a favorable environment. Seed treatments attempt to address one piece—the pathogen—but additional management can take care of both the environment and the host.

We can manage the environment by waiting for soil conditions to be correct. While not always possible, this is the best line of defense against most soybean seedling diseases. The diseases of concern all have a preferred temperature range. Avoiding temperatures in the ranges outlined in the accompanying table can decrease the likelihood of infection.

Perhaps more important than disease is proper soil moisture. Planting into fields with adequate—but not excessive—moisture is ideal for numerous reasons. Not only do many fungal diseases thrive in saturated conditions, but you also want to avoid compaction, which compound saturated conditions, hamper seedling growth and contribute to disease.

We can also manage the susceptible host component of the disease triangle. Selecting varieties with resistance to soil-borne diseases such as phytopthora or sudden death syndrome is the obvious place to start, but soil conditions can also have a huge impact on the amount of time a seedling remains vulnerable to infection. Anything that limits the amount of time a seed spends underground and promotes rapid growth of a young plant lessens the time a plant remains vulnerable to infection. We see this time and again in years where SDS is common. The fields affected most severely often have seedlings that endured stressed or prolonged emergence periods. Think about how much more vulnerable an infant is to the flu than a healthy adult. Proper temperature, moisture, depth and seed placement all impact the growth and development of the soybean plant just as much as the disease.

Managing diseases takes a multi-faceted approach. Over-reliance on any one method of control—cultural or chemical—can lead to disappointing short-term results. In the long term, that reliance can lead to the development of resistant pathogens. It is important keep integrated pest management strategies at the front of our decision-making process for immediate success and continuing efficacy of our control options.

Seeing is believing

Written by MFA Agronomy Staff on .

In 2017, more than 700 MFA employees, ag industry personnel and growers toured MFA’s Training Camp test plot in Boonville, Mo. Two events were held at the research site this year: MFA’s Sixth Annual Training Camp and MFA’s Annual Grower Field Day.

These events give participants hands-on involvement in our testing and product evaluation process. Attendees viewed trials on MorCorn hybrids and MorSoy varieties, soybean seed treatments and foliar nutritionals. They heard presentations from experts on spreader calibration, Bt corn traits, evaluating dicamba symptomology in the field, and breakdown of herbicide modes of action for corn and soybeans.

Beyond the educational opportunities these field days provide, multiple replicated testing sites across MFA’s trade territory delivered vital data for product improvement and evaluation. Here are some summaries and results of these trials at the Training Camp site.

MorCorn hybrid trials

The MorCorn trials were planted April 13 with a total of 37 hybrids ranging from 95-day CRM (comparative relative maturity) to 117-day CRM. We tested 12 MorCorn commercial checks against 24 experimental hybrids and one competitor hybrid. The field was fertilized with 300 pounds of actual nitrogen in the form of SuperU. The planting population was 32,500 plants per acre.

Yields were impressive once again at our site. The top end hit 258 bushels per acre with an experimental hybrid and a MorCorn commercial hybrid. At the bottom was a MorCorn commercial hybrid and an experimental hybrid at 189 bushels per acre. Results from this year’s MorCorn Training Camp trials can be seen in Figures 1A and 1B. In addition to the Training Camp trials, these hybrids were tested across multiple environments and geographies in 11 other locations within MFA’s trade territory.

MorSoy variety trials

In terms of growing soybeans, the region MFA serves is very diverse, which shows in the diversity in the MorSoy line. Our soybean maturities range from group 3.0 to a group 5.0, and traits include RoundUp Ready 2 Yield Technology, RoundUp Ready Xtend and LibertyLink along with conventional varieties. The MorSoy trials were planted May 31 with 54 varieties, including 37 MorSoy commercial checks against 15 experimental varieties and two competitors. The planting population was 140,000 plants per acre. We had four trials to compare by relative maturity ranges: Trial 1 was 3.0-3.6, Trial 2 was 3.7-3.9, Trial 3 was 4.0-4.5 and Trial 4 was 4.5-5.0. The trials included all of the herbicide technology traits combined, so weed control was maintained with a sound agronomic conventional herbicide program.

In addition to Training Camp, these varieties were tested across multiple environments and geographies in 12 other locations within MFA’s trade territory. Results from this year’s MorSoy Training Camp trials can be seen in Figures 2A, 2B, 2C and 2D.

N stabilizers

Nitrogen stabilizers used on urea such as Agrotain, SuperU and Instinct have been evaluated at Training Camp for several years. We have found it important to continue our evaluation of these products for a couple reasons. First, several products enter the marketplace each year, and many of those make claims to limit either volatility, leaching or denitrification as effectively as the products mentioned above without any proven activity when it comes to nitrogen stabilization. Second, weather conditions vary from year to year, and the different products may perform better depending on those conditions in relation to N application timing. For example, a product like Agrotain limits urea volatization; a product like Instinct stabilizes N below ground; and a product like SuperU provides protection above and below ground.  

To evaluate nitrogen stabilizers, we tested each product on urea applied at 80 pounds of actual N per acre. This low rate was used intentionally hopefully to prevent over-application of N and provide a better chance of separation between stabilized and unprotected urea. These treatments were compared against an untreated check and against unprotected urea applied at 190 pounds of actual N per acre. The results from this year’s trials can be seen in Figure 3.

The N responses were not as great as we might expect. Much of this is likely due to the fertile nature of the testing site. However, there are some things to note from this trial. The application date of all treatments was May 12, and the field did not receive a significant rain event until 0.75 inch of precipitation on May 18. This six-day period in which the urea was on the surface unincorporated would make volatization likely. The check receiving no additional N was the only treatment statistically different from the others. Agrotain, SuperU and Source NBPT—all of which contain NBPT, the active ingredient that combats the urease enzyme and limits urea volatility—all yielded higher than products without NBPT.  

Bt traits

This year’s Training Camp sessions included an insect resistance management presentation focused on Bt traits in corn. Discussions included management of rootworm and corn borer through proper trait selection, but much of the talk addressed the effectiveness of Bt traits on ear-feeding caterpillars such as western bean cutworm and corn earworm. We evaluated four traits with Bt technology: VT DoublePro, SmartStax, PowerCore and Viptera, all claiming to control a wide range of Lepidoptera insects. To demonstrate the impact of cross-pollination from refuge corn on the expression of the Bt trait in the ear, we detasseled one row of corn for each of the listed traits. Adjacent to the detasseled corn, we planted non-Bt corn to see if cross-pollination would dilute the expression of the Bt protein in the ear as compared to the stalk. To ensure insect pressure, 20 ears were infested with “lab-raised” earworm larvae or eggs, but feeding from the natural population was also observed.

During Training Camp, we pulled ears from the trial to show participants the differences between traits and the impact that cross-pollination had on ear feeding. What was quickly noticed is that the lab-raised earworms did not survive, and Bt traits worked well against them. We also noticed no difference in feeding from the natural population whether a row with a certain trait was detasseled or not.

The biggest finding came in evaluating the Bt traits against non-traited corn. In all cases, except with the Viptera, ear feeding was equal to that of non-Bt corn. Feeding and live earworms were found in over 15 percent of the ears in the SmartStax, PowerCore and VT DoublePro hybrids. The Viptera, which contains a Bt protein in the yet-to-be-released Tricepta corn trait stack, showed 100 percent control of both wild and lab-raised earworm. These observations show us that at least a portion of earworm populations have developed Bt resistance. However, current technology is still helping us control corn borers, a more serious concern.

Dicamba PPM trial

With the introduction of the new Xtend cropping system into our trade territory, we have been researching ways to reduce the risk to MFA and our member owners. For the past three years, we have looked at potential tank contamination issues. We also realized we needed to understand how off-target movement might affect yields. We established a study to look at low-dose responses of dicamba to non-Xtend soybeans. We treated soybeans with 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 ppm dicamba solutions sprayed across V3 soybeans. While evaluating the soybean variety, we noticed that the increased damage to the soybean plant correlated to the increase in ppm concentration. However, when we harvested the soybeans, we didn’t see any yield loss associated with this study. In short, the concentration of the solution was not high enough to cause yield loss in our particular situation. We will continue this study in the future, increasing our rates to a level that will show yield loss.

Bare-ground single A.I. herbicide breakout

For the past two growing seasons, we have had a bare-ground herbicide study to show the impact of using different active ingredients (A.I.) in herbicides to control weeds in both corn and soybeans. In this trial, we worked the ground to bare soil and started with a clean seed/weed bed. Plots were then sprayed with a single-mode-of-action (MOA) herbicide for both corn and soybeans. There are 12 single MOA herbicides for corn and 14 for soybeans. The natural weed pressure was then allowed to grow. This study allowed Training Camp visitors to visualize which MOAs are actively controlling or suppressing specific weed species and determine which would be beneficial for their own area/farms. We also include a couple of plots that were sprayed with a pre-emergence herbicide containing multiple MOAs followed by a post application of a multiple MOA herbicide to show the importance of overlapping residuals.

Figure 4 shows an example of a breakdown of a given herbicide with three different modes of action. In pictures A, B and C, you can see the effect that a single mode of action has on weed population 60 days after treatment. Picture D is a herbicide containing all three MOAs 60 days after treatment. This study emphasized the importance of having multiple MOAs to protect against weeds and weed resistance.

Spreader calibration study

Every year, we test nitrogen rate and timing at Training Camp. In these studies, we are often evaluating performance based on timing of application preplant versus a V5-V8 topdress application versus a split application. Rates often have been determined by N models or common grower practices. This year, we looked at rates influenced by spread patterns of fertilizer application equipment to demonstrate the importance of proper calibration. We took a fertilizer truck properly calibrated to spread a DAP/potash blend and pan-tested it with urea. The pans used to catch the urea were set up on 10-foot intervals from the center and on the edge of the 70-foot pattern. The first pan test was done with a 400-pound rate of urea (184 pounds of actual N). We repeated the pan test with a topdress rate of 200 pounds of urea to demonstrate that calibrations change as application rates change. In this truck, the result of spreading a lighter product such as urea when calibrated for a heavier DAP/potash blend was a high center pattern at the 400-pound rate such as the first graph in Figure 5A. A less exaggerated “W” pattern was seen at the 200-pound rate, similar to the third graph.

We used the pan catch from both tests to determine the percentage of the target rate at different distances from center of the spread pattern to set up our trial. The corresponding rates and yield data are included in Figures 5B and 5C (on page 43).

From this information, we concluded that, at the 400-pound rate, 71 percent of the spread pattern resulted in over-application by as much as 32 percent, and 29 percent of the spread pattern was under-applied by as much as 32 percent. At the 200-pound rate, 43 percent of the pattern was over-applied by as much as 100 percent of the target rate, while 57 percent of the pattern was under-applied by as much as 50 percent of the spread rate.

Though the only statistical difference in yield came between the untreated and the remaining checks at both timings, the importance of a properly calibrated spreader can be seen in nitrogen-use efficiency by limiting over-application across the pattern. In a year where N responses are higher, we can assume the under-application penalty would be much greater.

Doing our due diligence with dicamba decisions

Written by Dr. Jason Weirich on .

By now, you have likely heard that MFA Incorporated will have new internal policies for the sale and use of dicamba herbicides for the 2018 growing season. Our guidelines will be responsive to actual growing conditions based on field reports from our agronomists, crop scouts and other MFA personnel across our trade territory.

Once soybeans hit the R1 growth stage, MFA will no longer spray dicamba due to the inherent risk of off-target movement. We feel like it’s important to base our decisions on actual growth stages, and R1 is at the beginning of flowering. If we wait until too late in the season, we’re afraid that we will put too many soybeans in our territory at risk.

The Missouri Department of Agriculture has mandated that the cutoff date will be June 1 for 10 counties in the Bootheel and July 15 statewide, and MFA will adhere to those rules. But because MFA’s policies are based on plant maturity rather than calendar dates, our policy could be more restrictive than state guidelines. In other words, we may stop spraying well before those dates if conditions dictate.

To determine when to halt dicamba applications, MFA will launch an intensive scouting protocol this spring to track soybean growth and provide timely information to applicators about crop progress. We are establishing a network of “sentinel plots,” representing the average planting dates and maturity ranges of soybeans in different regions of MFA’s service territory. These plots will be scouted every Monday and reports sent to all MFA employees on Tuesday mornings with notes about maturity and potential cutoff dates for spraying dicamba. Applicators will be alerted when the majority of soybeans in their area have reached the reproductive stage, when dicamba injury can do the most harm to non-target plants.

As part of these guidelines, MFA Incorporated will only use the new dicamba formulations authorized for use with dicamba-tolerant crops, including Monsanto’s XtendiMax, BASF’s Engenia and DuPont’s FeXapan. We will not custom-apply or sell over the counter any old formulation of straight dicamba products such as Banvel, Clarity and Detonate. This does not include blended products such as Range Star, DiFlexx and Status.

Most growers are well aware that these actions are in response to widespread complaints that dicamba herbicides drifted and harmed non-tolerant crops during the 2017 growing season. Nationwide, 3.6 million acres of soybeans suffered harm associated with dicamba, and states launched 2,708 investigations into dicamba-related crop damage, according to data compiled by the University of Missouri. Missouri received about 310 complaints from growers related to dicamba, second only to the nearly 1,000 filed in Arkansas.

Arkansas has effectively banned dicamba’s use by setting April 15 as the cutoff for applications. We’re still waiting to hear if other neighboring states in MFA geography, such as Iowa and Kansas, set dates that fall outside our own guidelines. Otherwise, we will follow MFA’s policies in those areas.

In Missouri, the Department of Agriculture requires anyone spraying dicamba to have a certified private applicator license or certified commercial applicator license, the latter of which applies to MFA employees. Before purchase or use of the product, both private and commercial applicators must complete mandatory dicamba training provided by the University of Missouri Extension. We are working with MU’s Dr. Kevin Bradley to make sure MFA applicators receive this training.

We need dicamba technology to combat weed resistance, but we have to be good stewards. Protecting the technology for the future is important, not only from an economic standpoint but also an environmental standpoint. This technology is up for renewal by the EPA in December 2018, and if we have another outcome like we did last year, we may not have this tool anymore.

We hope MFA’s proactive move will set a trend so that other companies, applicators and farmers will follow our lead to help protect this technology.

We will be posting the latest information on mfa-inc.com/news throughout the growing season.

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