The cold temperatures arrived quickly in Manitoba. And with those cold temperatures and the minimal snow cover, I received my first “how is the winter wheat doing with the recent cold snap?” question of the 2014/15 winter wheat crop year!
The quick answer is the cold snap likely hasn’t had much of an impact. In looking at the soil temperatures in the four winter wheat fields we have real-time monitoring in (see the CropChatter post at http://cropchatter.com/real-time-regional-winter-wheat-in-field-soil-temperature-monitoring/), soil temperatures have dipped around the minus 5 degree Celsius mark. Fortunately, winter wheat is at its hardiness in November and December (see below Figure). Also, in the late fall (prior to Dec. 20), the soil has a large heat capacity and decreases in soil temperature lag considerably behind decreases in air temperature. Therefore, the probability of the recent cold snap damaging the winter wheat crop is very low.
We also need to remember that many winter wheat acres were seeded under “optimal” conditions, including before or at recommended seeding dates, into fields with standing stubble, and into good soil moisture helping the crop emerge quickly and uniformly (reaching the recommended stage of 3 leaf to 1 tiller prior to snow fall). These best management practices lend themselves to a winter wheat crop that is well-hardened.
However, even with those positives, we still need good snow cover starting mid-December to protect the crop from the sustained cold temperatures we typically see in January and February in Manitoba.
Submitted by: Pam de Rocquigny, Provincial Cereal Crops Specialist, MAFRD