Published on Wednesday, February 22, 2017
Earlier this month I sent an update discussing how the warmer weather could affect nitrogen (N) applications on wheat. With another stretch of unseasonably warm weather upon us, I thought it would be a great time to provide a quick update on our wheat crop.
Many of the conversations I’ve had over the last week have centered around the warm temperatures and the uncertainty many farmers are facing over when and how much N to apply. With above average temperatures in the forecast for much of the next two weeks, this wheat crop has undoubtedly broken dormancy and is beginning to grow! Some farmers have asked about delaying N applications in an attempt to prevent excessive growth and even slow wheat growth due to concerns of potential frost. However, I think it is important to manage your applications based on the wheat growth stage rather than the calendar date.
For example, I recently scouted wheat at Feekes 2 (tillers forming) up through Feekes 5 (leaf sheaths strongly erect). For those fields coming out of dormancy at Feekes 2, this is a good opportunity to add more N up front to promote more tillers. For wheat that is breaking dormancy at Feekes 3, where there is good tiller formation, a split application can still be successful. But, as the wheat crop progresses over the next few weeks, that second N application at Feekes 5 may come much earlier than what we would consider “normal”. As I mentioned, I have found some fields passing Feekes 5, where the first node is at the soil level, meaning that these fields are at the point where rapid N uptake will begin to occur. For these fields, delaying N applications may negatively impact yield as the number of kernels are being determined.
Below is a chart from the University of Kentucky Wheat Management Guide that shows how a frost can affect wheat at various growth stages. With much of the wheat in southern Illinois between Feekes 3 and Feekes 5, the crop should handle temperatures down to 12°F. Keep in mind that in fields that are further ahead, once joints are visible, frost damage can occur if the temperature drops to 24°F for two hours or more.
The potential for frost will remain a possibility throughout the next 60 days or so. It is important that we continue to manage this wheat crop for success by making timely N applications based on our knowledge and understanding of the wheat growth stages. Another thing to consider is an application of herbicide and insecticide because as the wheat grows, so will the winter annual weeds that are present in our fields. Consider making these applications earlier than normal as well.
As you scout your fields this week, be on the lookout for aphids. So far, I have only found them in a few isolated pockets, however I have received reports of insecticide applications being made to control aphids in areas of southern Illinois this week. If you have any questions regarding your wheat crop and its growth stage, or if you need help identifying weeds or insects in your wheat fields, please contact your Beck’s dealer or seed advisor.
Author: Sean Nettleton
Categories: Agronomy, S Illinois
Tags: Aphids, Wheat, Illinois Agronomy, wheat growth stages, Sean Nettleton, Ag Chat, Nitrogen Management on Wheat, Feeks Scale, wheat management