Thursday, January 31, 2019

A Wicked Wisconsin Winter!

January closes with weather extremes southern Wisconsinites have not experienced in decades.  Intensely harsh winds accentuated extreme sub-zero temps as people (and plants) struggle to survive.  

As we tackled huge snow drifts with shovels and snow throwers, we likely weren’t thinking of our plants’ root systems beneath the snow.  Often plant survival depends on a thick layer of “insulating” snow cover to reduce effects of wind damage and piercing sub-zero temperatures.  
Also, a healthy plant (not a weak, stressed plant) stands a better chance of survival through winter—just like healthy humans!

When spring arrives in Wisconsin (eventually gentler, warmer spring days WILL come…) our trees, shrubs and perennials will reveal any damage sustained over winter.  Often the deep cold is NOT the problem; some trees and plants can survive even if their entire root system becomes frozen.  

More problematic are numerous freeze-thaw cycles that springtime brings.  
These alternating patterns of freezing temps, followed by warmer temps, followed by more freezing temps… send mixed messages to our perennial plants.  As they emerge from dormancy with blissful sunshine and warmer temps, they are vulnerable.  Dropping below freezing again can shock these plants, or kill them.  

Some prevention methods are effective, but must be done in autumn before bitter cold days arrive.  Lightly wrapping large plants in plain burlap fabric can protect against sunscald and windburn.  The 3 - 4” layer of shredded hardwood you had placed around plants (to reduce moisture loss and deter weed seeds from germinating) also helps insulate plants’ root systems against freeze-thaw cycles.

Rodent damage
Voles (genus: Myodes) are often active in winter beneath the snow.  Voles are rodents related to mice, but not the same; easy to identify with a flatter face than mice, as well as a shorter tail and smaller ears. There are more than 150 species of voles throughout the world. Voles are destructive with tiny “needle teeth” and can easily girdle a tree trunk or shrub beneath the snow.  Voles also eat succulent roots and roots of ground cover. (I snapped this picture  last summer when a vole accidentally found its way into a mouse trap.) 
Voles are often eaten by a variety of owls, so do NOT place poison to reduce their numbers.

As we enter February, each day is one day CLOSER to spring!  Keep warm!

M. Lynn Schmid,   Certified Master Gardener
A.A.S. Landscape/Horticulture/Arboriculture