Field Observations
SPRING 2025
April 17, 2025
This is the first field observation of the year after what seemed like a never-ending winter. At the start of April, we have certainly seen some swings in weather, from six inches of snow in some regions to plenty of rain. Finally, with some beautiful weather on the horizon, Ontario certainly has experienced it all. But, with these weather events experienced, there has been some impact on the winter wheat crop.
Winter wheat
Due to the excessive snow in some regions, snow mould has been a concern. Snow mould occurs when the ground does not freeze enough before snow accumulation. The snow insulates and allows pathogens to survive and grow on plants throughout the winter. Once the snow has disappeared, damp, cool conditions allow for further pathogen growth and continue damaging the plants. More information on snow mould, how to identify it, and how to assess plants for yield loss can be found here. If a high incidence of snow mould has occurred, aim to plant in the optimum planting date in future years. The optimum planting date map can be found at GoCrops.ca.
frosty mornings. Photo supplied by Marty Vermey
Some areas have experienced ice encasement of wheat due to water ponding and then freezing. When this occurs, the ice traps carbon dioxide and suffocates the plant by inhibiting respiration. Some plants may be dead, and some may be weakened. Be sure to scout and assess for plant stand. There are four main steps when assessing spring plant stands. Read more in the A Visual Guide to Winter Wheat Staging, pages 18 and 19.
When scouting, purple tissue may be identified—stress from the past week of cold temperatures has set the plants back a bit. When the soil is cool and wet, phosphorus uptake slows. Also, yellowing on the leaves at the bottom of the plant might be noted due to wet roots from saturated soils.
As fields green up and begin actively growing, keep an eye on growth stages as timing for a T1 fungicide, herbicide applications and/or the start of the optimum window for most plant growth regulator applications will be soon approaching at GS 30 (stem elongation). Some areas have begun the first pass of nitrogen on winter wheat in the deep southwest.
