Growing Knowledge

Read the latest insights from our experts as they cover agronomy issues that matter most to you and your operation.

Enhance Your Variable-Rate Fertility on Wheat

Chris Heidrich
Are you looking to boost the yield and ROI potential of your wheat crop? If so, more intense, targeted nutrient management in areas where it will be most effective could help you push your crop to the next level of bushels per acre and protein content. Here are some tips to help you optimize fertility in your fields.
 
1. Start with a soil sample.
Zone soil sampling can give you valuable information about nutrient variability in your wheat fields and, depending on your region, can be more cost-effective than grid sampling. Talk with your local trusted advisor about getting soil samples now prior to freeze-up and snow cover.
 
2. Choose the right varieties.
Ask your advisor how the Characterization Charts (CHT Tool) function of the R7® Tool can help you choose the wheat varieties that will best meet your production goals. High management on varieties with high response-to-population, response-to-nitrogen and response-to-fungicide scores can help you boost both yield and quality potential at harvest. If you do choose a high-management variety, work with your agronomist to time input applications appropriately.
 
3. Manage by zones.
Establishing yield goals by zones is critical to help determine how much fertility you need to apply in each area. Work with your advisor next season to use satellite imagery, prior year crop removal and past yield results to set yield goals for each management zone on your operation with the R7 Tool.
 
4. Pay attention to nitrogen and sulfur.
These macronutrients play important roles in wheat development and in quality and protein content at the end of the season. If your nitrogen-to-sulfur ratios are optimal late in the season, you have a better chance of achieving the protein and quality levels you desire. A number of farmers use variable-rate split nitrogen, which is an application of nitrogen at the beginning of the season, with another at flag leaf or post-flowering for a protein boost.
 
5. Look at the data.
In 2015, 2016 and 2017, my colleagues and I performed side-by-side variable-rate and static-rate checks on farms in western North Dakota and eastern Montana where variable-rate fertility applications were being performed on wheat for the first time. These were not scientific trials and there was no attempt to replicate the trials. The objective was to give farmers some perspective on how variable-rate fertility applications could potentially impact yield in their fields.
 
As we compiled yield data from the trials, we found crops that received variable-rate treatments outyielded the static strip by an average of nearly 4 bushels per acre.*
 
Selecting the right varieties, getting population right, doing variable-rate nutrient applications, and using technology to detect disease and weed pressures can help you give your wheat crop the level of management it deserves. And help you reach the goals you want to achieve. 
 
 
* Source: 2015–2017 customer field trials (52 locations in Montana and North Dakota). Because of factors outside of WinField United's control, such as weather, applicator factors, etc., results to be obtained, including but not limited to yields, financial performance, or profits, cannot be predicted or guaranteed by WinField United. Actual results may vary.
 
© 2018 WinField United. R7® and WinField® are trademarks of WinField United.
 

Joel and Jon
Hosts, WinField United
On this episode of the Deal With Yield, hosts Joel Wipperfurth and Jon Zuk discuss the various challenges impacting this year’s harvest, including compaction, common disease pressures like SDS and nutrient deficiency trends in corn. The guys look to answer the question, “Is there a connection between disease and fertility?”

The Deal With Yield is a podcast series covering the issues that matter most in crop production.

5 Tips for Fall Nitrogen Management

Tyler Steinkamp
Regional Agronomist
Nitrogen is a tough nutrient to manage. It can be immobilized, volatilized or leached before plants even have a chance to uptake it. As you consider fall nitrogen applications, here are five tips to make the most of your dollars and time.
 
  1. Watch soil temperatures. Before you apply your fall nitrogen application, be sure the soil temperature is at 50 degrees and declining. Nitrification can take place when soils are above this threshold, making the potential loss over the winter relatively high.
 
  1. Split your applications. With fall-applied nitrogen, you’re many months away from crop uptake. About 75 percent of a corn plant’s nitrogen is taken up before tassel, and 80 percent of that is taken up between V8 and VT. Even with a nitrogen stabilizer, there is a decent potential for loss during those months between a fall application and crop uptake.
 
Spoon-feeding nitrogen throughout the season can favor plant availability. Start with ammonia in the fall, follow that with an at-planting application with your herbicide to get the crop up and running, and finish with a side-dress nitrogen application around V5.
 
  1. Check hybrid response. The amount of nitrogen you apply will vary each year depending on yield goals, weather conditions, crop rotation and the hybrid’s response to nitrogen (RTN). If your hybrids have a high nitrogen response, I’d recommend applying more nitrogen with spring applications. I tend to recommend variable-rate applications in the spring rather than the fall depending on the hybrid’s RTN, the rainfall amounts and the previous crop.
 
  1. Stabilize your nitrogen. Nitrogen stabilizers slow down the conversion of ammonium to nitrate, which is critical to keeping nitrogen in a form that prevents leaching. I recommend using nitrogen stabilizers with every fall application and potentially with early spring applications, depending on the amount of nitrogen applied. Even at planting, you’re 60 days from when the crop will use most of the available nitrogen, so there’s still potential for significant loss.
 
In Iowa, N-Serve® and Instinct® are two popular products used to help stabilize nitrogen. Based on 452 trials from 2010 to 2016, there was an average 8.9 bushel per acre yield increase when Instinct and N-Serve were applied to corn*. In addition, corn trials treated with NutriSphere-N® produced an average 10.0 more bushels per acre versus untreated checks, demonstrating the effectiveness of adding a nitrogen stabilizer to your application.* 
 
  1. Don’t forget sulfur. Without enough sulfur, plants aren’t able to use nitrogen efficiently. For every 10 units of nitrogen applied, a unit of sulfur should also be applied. That can come in the form of elemental sulfur in the fall or an AMS or ATS product in the spring. Elemental sulfur doesn’t release quickly, so I recommend no more than 50 percent of sulfur needs come from elemental sulfur or gypsum. The other 50 percent of sulfur can be applied in the spring with an AMS or ATS product.
 
Keep these tips in mind as you prepare for postharvest nitrogen applications. Contact your WinField United retailer for more information on best nitrogen management practices.
 
* Based on Verdesian Life Sciences and Dow AgroSciences data on file.
NutriSphere-N® is a trademark of Verdesian Life Sciences. N-Serve® and Instinct® are trademarks of Dow AgroSciences.

4 Ways to Leverage Tissue Sampling Insights in the Off-Season

Corey Evans
Technical Seed Manager
The majority of farmers who choose to take tissue samples are looking for in-season insights to help them fine-tune their fertilization programs. But tissue nutrient analysis can also tell you a lot about your production practices and identify changes that can be made to improve productivity. Here are four ways you can use tissue sampling results in the off-season to make changes to your management practices.

1. Soil and tissue analysis comparison can reveal potential problems. When used together, soil and tissue testing can help you identify potential issues in your field. For example, if soil analysis reveals you have ample nutrients present but tissue testing shows that they aren’t being taken up by the plant, that’s an indication that there may be issues with root growth caused by compaction, environmental conditions or shallow planting.

2. Tissue sampling helps calibrate the Field Forecasting Tool. The R7® Field Forecasting Tool (FFT) delivers more accurate results as new information is added to the model. The tissue sampling results from the NutriSolutions® app can be automatically fed into the FFT and can help estimate yield potential in-season. The model can also be used in the off-season to help establish management practices for the future that can reduce the gap between the forecasted yield and the actual yield.

3. Evaluating nitrogen trends can help with seed selection. If you find your plant nitrogen levels are often trending low, you might choose to be more aggressive with your nitrogen applications. But if you’re looking to maintain input costs, an alternative would be to place a hybrid that has a low response-to-nitrogen score on those acres in the future, knowing that nitrogen could be limiting.

In 2017, we tested 210 hybrids at our Answer Plot® locations and found 36 percent were highly responsive to nitrogen, 45 percent were moderately responsive and 19 percent were less responsive to nitrogen. Across the tested hybrids, there was a 39.5- to 97.2-bushel-per-acre yield response gradient, illustrating the vast differences genetics can have on nitrogen utilization in plants.

4. Choose the right seed if zinc comes up short. If tissue sampling trends reveal an early-season zinc shortage, consider using CROPLAN® corn hybrids on your acres. All CROPLAN hybrids are treated with Advanced Coating® Zn seed treatment. By coating seeds with zinc, Advanced Coating Zn promotes quick emergence, even in cool, wet conditions, and it helps establish strong, healthy stands. In nearly 180 Answer Plot program test plots over three years, corn treated with Advanced Coating Zn seed treatment averaged an extra 2 bushels per acre.
Don’t put your tissue sampling results on the shelf once you’ve used them to make in-season decisions. Evaluating nutrient data in the off-season can help you develop a more comprehensive crop management plan that includes mapping out management zones and choosing the right hybrids and seed treatments based on what nutrient trends are showing. Work with your WinField United retailer to put your tissue sampling results to work in the off-season.
 
Advanced Coating®, Answer Plot®, CROPLAN®, NutriSolutions®, R7® and WinField® are trademarks of WinFIeld United.

Subscribe to the Advisor Newsletter

Sign up for monthly agronomic insights and product information.