Digital Corner 

by Dale Cowan

Nutrient Uptake in Winter Wheat

At the recent Ontario Ag Conference in Ridgetown I listened to research presentation by Peter Johnson and Dr. Joshua Nasielski. They summarized the research they had done on nutrient uptake and partitioning of essential nutrients in winter wheat. This is a valuable piece of research as it indicates when nutrient uptake peaks at a particular growth stage and how much a particular nutrient tends to remobilize after uptake. We have this type of information for corn and soybeans and now this research completes the crop rotation. For an agronomist advising farmers on when to apply a particular nutrient can greatly influence uptake and yields. I am going to highlight Nitrogen and Sulphur for spring applications

Starting with nitrogen (N) uptake, wheat takes up 85% of its nitrogen needs before flowering. In contrast to corn that only takes up 65% to 67% of its N by flowering stage. Depending how a farmer chooses to apply N either as split application with some at green up and some at stem elongation or a single application after green-up, the point is the majority of the N needs to be applied ahead of the flowering growth stage. With only 15% of the N taken up after flowering there is risk in delaying N applications too late in the season.

What is noteworthy, at the beginning of stem elongation the wheat crop has already accumulated 40 kg/ha or 36 lbs / acre of its total N needs for the season. This will largely have come from fall growth and a combination of any fall applied N from phosphate fertilizer such as MAP and residual nitrogen. The other important observation is the remobilization of nitrogen from the leaves and stems to the grain. This speaks to the importance of maintaining a healthy green canopy all the way through grain fill. Often requiring the use of fungicide applications to preserve plant health when foliar leaf disease is severe.

This graphic above represents a high yield environment indicating a total uptake of 208 Kg/ ha or 187 lbs. per acre of N. Uptake includes the grain, and stem and leaves. We do not apply this rate of nitrogen. N application rates are in the range of 110 to 130 lbs. of actual N typically, with the balance of N uptake coming from mineralization of organic N sources in the soil. The harvest Index is the amount of total N uptake that is harvested in the grain. In this example 72% to 83 % of the N is found in the grain.

Sulphur uptake is even more dramatic with 91% of the sulphur taken up by flowering growth stage. Total uptake of 16 kg/ ha or 14.4 lbs. per acre of sulphur in this study. Again, much like N it is remobilized to the grain after uptake. The harvest index is 56 % to 65% not as high as N but a significant amount is remobilized to the grain. It is important to apply S early well ahead of flowering time to optimize uptake. Only 2.5 kg/ ha or 2.2 lbs./ acre of the S is in the plant at stem elongation so spring is when maximum uptake occurs. The sulphate sulphur is the readily plant available form found in ammonium sulphate, Ammonium Thiosulphate (after rapid conversion). These two are most popular choices to apply with N, other sources are gypsum, potassium sulphate and KMag.

Having a deeper understanding of nutrient uptake and partitioning of essential nutrients should lead to minimizing the size of our environmental footprint, optimize harvested yields and maximize nutrient use efficiency.

I encourage you to work on your Crop Plans for nutrient applications on Wheat with you AGRIS Crop Sales Specialists. 

Crop Planning Is Time Well Spent 

With the first month of 2024 coming to an end, many growers will be looking towards the upcoming planting season. To avoid stress come spring, now is the perfect time to sit down with your crop sales specialist and discuss your strategic farm plan. For example, what crops are being planted? Which fields are being used? What herbicide program are you considering? Is it compatible with your purchased seeds? With a wide variety of genetics available and many different herbicide products that can be used on each variety, it is beneficial to take some time to investigate your options. What would produce maximum yields on your soil type? Now may also be a good time to discuss fertilizer programs as spring applications are just around the corner. Soil sampling is a great option to consider if you would like more insight on your soil’s fertility status.

Putting all of these ideas into written plans for the year will help you stay organized and focused, while also saving time later on. Another added benefit when it comes to planning, is that you can organize when products will be needed. If the resources are available, it may be helpful to take possession of products early as opposed to spring.

Finally, a friendly reminder that now is the time to finalize your 2024 seed order. Even though pre pay orders were completed in December, now is a great time to fine tune those orders! If you have any questions, please reach out to any AGRIS representative and we will be happy to help!

Crop Planning for 2024 

by Graham McLean

Getting ready to complete crop plans for 2024 season often relies on a review of 2023 outcomes. One of the first items that comes up is whether or not we have current soil tests to base nutrient applications upon, nothing older than 4 years.Much like a financial balance sheet you would not make current decision to purchase anything from a balance sheet from 2018

If you have a FieldView account the satellite imagery that is produced close to pollination in corn and flowering in beans will give you a good indication of how variable the field might be and offer insight into how variable crop removal of nutrients would be. Which may lead to the realization that a uniform application of fertility may not be the best strategy for 4 R Nutrient Management.Of course, a yield map is most valuable if you have the technology. Second best is using Fieldview imagery and weigh tickets to generate one.

Variability with in the field has been tremendous.

6 areas that I would start with are:

• Yield Goal/ Selling Price ROI
• Fertilizer Recommendation P&K
• Nitrogen application- source and timing
• Herbicide Decision
• Fungicide Application
• Foliar Applications

One should determine yield goals on a farm by farm, field by field situation. One should look at the ROI -return on investment with a budget of selling price and yield goals in mind. A simple return to land, labour and equipment will help predict a positive outcome. The results can be an eye opener.

Putting fertilizer recommendations in for a Phosphorus and Potash application driven from the current soil test and previous crop yield is good place to start to evaluate a program.

If soil tests are trending lower that simply means the crop is removing more than what is being applied. Conversely if soil test levels are increasing nutrients are being applied at a level that exceeds crop removal. Our approach of build, when test are low, maintain when test are at the right range and draw down when they are excessive. Is designed to comply with a responsible 4 R Nutrient stewardship program. Often times starting with the manure nutrient applications first then moving to top up with fertilizers yields the best results. A variable rate application optimizes the fertility plan.

Managing nitrogen as a system leads to better nutrient use efficiency. Starting with Yield Goals and taking into account soil texture, soil organic matter previous crops including cover crops, any previous nitrogen applications from manure, starter fertilizers moves us closer to the optimum rate of nitrogen.

Splitting nitrogen applications amongst starters, early and late side-dress and use of nitrogen stabilizers can match the nutrient uptake of corn more closely. The first 50 days of corn growth, accumulates 35 pounds of nitrogen. Spreading out the application matches uptake patterns

Herbicide decisions are not as easy for many reasons. Multiple modes of action are a must with the resistance that exists in the area. Knowing the weed spectrum and crop rotation will help choose the appropriate herbicide. Understanding the groups that correspond to the trade name will help with planning for entire season long control.

Fungicides are proving more advantageous each year with the onset of Tar Spot This can be added into our planning activities. Keeping the canopy greener longer improves nitrogen use efficiency reduces stalk rot and improves the last 40 days of grain fill where most of the yield occurs

Our planning approach is by farm, by field, by crop, by product. Execution of individual plans depends on the growing season stresses encountered. Plan for good things to happen.

The old saying is very true, “failure to plan, is planning to fail”

Call us to today to start planning!