Winter wheat can normally withstand cold temperatures well as long as soil temperatures at the depth of the crown are not in the single digits for a prolonged period of time. Soil temperature is a more important consideration than air temperature alone during the winter.
In most cases so far, soil temperatures have not been cold enough to create concern for the wheat. Where you might get some damage would be if plants were weakened by other factors, such as greenbug or aphid feeding, Hessian fly infestation, wheat streak mosaic, or drought stress. In those situations, soil temperatures at the crown depth wouldn’t have to get so cold to cause additional injury to the wheat.
Last year at about this same time, soil temperatures at the 2-inch depth at Scandia dipped into the single digits. And there was some winterkill on certain varieties last year, especially where wheat was planted into dry fluffy soils with poor seed-soil contact and on exposed slopes.
Producers can check their fields for winterkill injury by digging up some plants and bringing them inside. After a week or so of warm conditions and water, wheat should begin greening up if it is alive. Otherwise, producers can wait until spring green up begins in the field. Areas of dead or dying wheat should be noticeable at that time. Be aware, however, that damaged wheat may begin to green up then die back later.
Jim Shroyer, Crop Production Specialist Emeritus
Mary Knapp, Weather Data Library