Evaluating winter wheat plant stands
One of the hardest decisions when growing winter wheat is evaluating the amount of winter kill and deciding whether to keep a stand.
Optimum plant stands of winter wheat can be less than that of spring wheat. A stand of 900,000 to 1 million plants per acre or 21 to 23 plants per square foot will be enough to maximize grain yield.
Winter wheat is planted in the fall and develops in the spring during relatively ideal conditions for tiller development. During the Minnesota winter, you can expect some winter kill.
Winter kill is likely when there’s extreme cold, little snow cover or where winter wheat was planted on fields with little to no standing stubble to collect limited snowfall.
Roots are generally less winter-hardy than crowns and regrowth may be very slow, even if roots and shoots appear dead.
However, winter survival will vary within a field and depend on topography. For example, windblown hilltops may have less stand than protected areas of the field.
Impact on yield
If your stands are uniformly reduced across the field, stands of 17 plants per square foot can still produce near-maximum grain yields. Even stands as low as 11 plants per square foot can still produce yields of 40 bushels per acre.
When spring arrives late
Very cool and wet weather in the spring means fields will be slow to green up. For example, sometimes it’s not until May when winter wheat puts on new leaves and tillers, and producers can do a fairly straightforward evaluation of surviving plant density.
Replanting and interseeding
A late spring also increases the likelihood that anything else that’s planted will be planted later than optimum, creating another incentive to stick with a less-than-ideal stand of winter wheat.
Consider interseeding spring wheat to fill large gaps. However, be prepared for the fact that spring wheat matures later than winter wheat, so harvest will be problematic. Furthermore, mixing wheat classes can cause problems at the elevator.
Planting winter wheat into large gaps could be another option. Winter wheat planted in the spring will not vernalize, so it will not produce a head (or there will be fewer late heads). However, it will provide ground cover until harvest.
Reviewed in 2018