In John Bates' column from last Friday, he says he doesn't remember temps hitting 30 below zero since the winter of 1966-67, nearly 20 years ago. And, I heard someone else observe that we had 88 consecutive hours when the temp never rose above zero. (That's three 24-hour periods plus 16 more hours.) It's certainly been a deep freeze, both here and throughout the rest of the Midwest too.
Bob Ruch drew my attention to an NPR feature, saying that the invasive emerald ash bore which has been destroying trees in more than 20 states, will have suffered from the extreme cold. The researcher said, "Eighty percent of emerald ash bore may have been destroyed where temperatures fell to -22 to -26 Fahrenheit."
(This photo is of a Minneapolis park, where each of these trees are marked in green to be removed. You can see the stripes, if you click to enlarge the photo.)
The same scientist reports that gypsy moths may have met their match. These insects have moved into northern Wisconsin and Minnesota and have been eating the leaves of more than 300 species of trees, shrubs, and plants. However, they cannot survive temperatures lower than minus 17 degrees F.
More good news is from the scientist who stated, "The population of some kinds of ticks, which have been advancing farther north than ever before, should be reduced by the bitter cold, too." I couldn't find other references to ticks, but the word around town is that folks are expecting this cold weather to reduce wood tick populations.
I have read that the freezing days will also be a blessing for the Great Lakes. More ice cover could limit evaporation and help the lakes, which have seen shipping affected as their levels have fallen because of drought. And of course, more ice cover on Carlin Lake will also limit evaporation for us.
What will NOT be affected by the deep cold: most of our strong native species. Our fairly deep snow cover acts as an insulator, protecting the root system of local hibernating plants.
If you are interested in more info, I just googled polar vortex and words like plants, animals, wildlife, etc.