Soft Red Fertility Requirements

Do a stand count, then make a plan!

There are many different factors that need to be evaluated shooting for BIG wheat yields. Since the fall management strategies such as variety selection, residue management and planting have all been looked after; it is time to start planning the spring management. The first step in the spring is to get out in the fields and do a plant stand assessment and tiller counts. Ideally we want to see 15 healthy plants with 2-3 stems per foot of row. This will give us 450-600 heads per square yard. This provides us optimal yield potential with minimal lodging risk. The total number of plants and tillers per foot of row will help determine the nitrogen requirements.

When we look at Soft Red Winter Wheat compared to Hard Red Winter Wheat in terms of nitrogen requirements, the main difference is protein targets. As a result, the nitrogen rates for SRWW can be reduced because we are not shooting for high protein levels. The standard rate for Ontario wheat producers is 120lbs N /ac. However, this rate can vary plus or minus based on yield goals, soil type, soil fertility levels, crop rotation and historical manure applications. Some producers are pushing upwards of 150lbs+ of N in combination with plant growth regulators.

One of the best nitrogen management practices for Ontario wheat growers is split applied nitrogen. Split applying allows growers to tailor their nitrogen program specifically to the crops demand. This ensures the nitrogen is utilized efficiently thus reducing nitrogen losses and lodging risk. For instance, the wheat crop does not need 120 lbs N/ac at GS 22. By splitting the applications we are ensuring the nitrogen is applied following 4R principles – Right Source, Right Rate, Right Time and Right Place.

As mentioned in the Hard Red Nitrogen Options article, KickStart > Yield Maker > Protein Push are terms we use for nitrogen management strategies in winter wheat. Since this article is only focused on Soft Red nitrogen options, we do not need to discuss the “Protein Push” application.

The first application of nitrogen is what we call the “KickStart”. This gets the young plants off to a good start right out of the gate in the spring. The sulphur should be applied at this time. The second application is what supports the plants demand nutrients during head formation and grain fill; we call this the “Yield Maker”.  This stage is typically around zadok’s growth stage 31-32.  Nodes are detectable, and stem elongation occurs at this point, which means we are past the point of creating more tillers.

The next question is “how much do I apply for KickStart and Yield Maker”? That answer really depends on the spring stand assessment and tiller counts. If we are in a situation with thick stands (over 15 plants/foot of row) and high tiller counts (more than 2 tillers) early spring, we are in a very high lodging risk which makes split nitrogen even more crucial. We want to make sure we maintain fertility but do not over stimulate. In this scenario, apply 40% of the nitrogen at KickStart and 60% at Yield Maker. On the other hand, if the stand assessment and tiller counts come in low we need to encourage tillering and early plant vigor. Apply 60% at KickStart and 40% at Yield Maker.

Every form of nitrogen has their pros and cons whether it is liquid or dry or a combination. Every grower needs to work through their cost of production and determine which system fits their operation and generates the greatest return on investment.

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