The Positive Side of 30 Below Zero?

All right, I had to think for a while to find the bright side of temperatures of about 30 below zero and wind chills of 60 below! But I happened to think about insect pests that we deal with every year that overwinter in Minnesota. Aren't these extreem temperatures affecting their survival? You would think these cold temperatures would at least kill some of them and decrease the insect pressure the next growing season.

So, I checked with Claire La Canne Extension Educator in Rice and Steele. I knew Claire's graduate work was entomology so she would know about how insects overwintering in Minnesota. So, for example the Emerald Ash Bore that kills ash trees. They are killed when temperatures drop to about 30 degrees below zero. Maybe these temperatures are cold enough to at least thin out the population of Emerald Ash Bores.

Then there is the Soybean Aphids that are overwintering as eggs on buckthorn plants. Claire said temperatures of about 30 below zero can crystalize the eggs on buckthorn plants and kill them. Some of them might have snow on the leaves and provide enough protection to allow them to survive. However, it would be safe to assume some of them would be killed and maybe decrease the chances of soybean farmers seeing threshold treatment levels next summer.

Finally there is the Western Corn Rootworms that feed on corn roots. The good news is that the eggs overwintering in the soil are killed when temperatures reach about zero degrees. The bad news is that soil temperatures are about 20 degrees at the 2, 4 and 8 inch depth according to the official weather station at the Southern Research and Outreach Center at Waseca. Because of about 10 inches of snow that is very good insulation. The corn rootworm eggs are nice and warm, even though air temperatures are cold enough to kill them.

So, I know it is a stretch to think there is a "bright side to temperatures of 30 below zero. This is the best I can come up with! In fact, it's cold no matter if it is 30 below zero or 35 below. mMybe we should hope for 35 below to kill more insects?