Originally published in the Kenosha News
By Horticulture Educator, Jeanne Hilinske-Christensen
It’s been a wild winter! Extended days of subzero temperatures, high winds and mixed precipitation have plagued our region disrupting school schedules, travel plans and morning commutes. As humans, we have the ability to alter behavior in response to winter woes, but plants, the immobile inhabitants of our landscapes, are rooted in place, having to endure the elements to which they are exposed.
Dr. Brian Hudelson, director of the University of Wisconsin-Madison Plant Disease Diagnostic Clinic, shared his thoughts on the possible adverse effects of this winter’s weather in his monthly column posted on the clinic’s website: https://pddc.wisc.edu/.
The frigid, sub-zero temperatures undoubtedly damaged plant material. Physical injury to branches and trunks may be evident once the growing season begins this spring. Signs of injury will include trees and shrubs that don’t leaf out, lack of flowers, and branch dieback. Some plants, especially those marginally hardy in our area, may not have survived. Plants like magnolia, redbud, Japanese maple and fruit trees, such as peach, most likely will exhibit injury.
Strong winds dehydrated plants causing damage referred to as winter burn. Symptoms of this include brown or bleached needles and branch dieback. Plants that may exhibit this type of damage include boxwood, arborvitae and Alberta spruce. Intense, strong winds may have caused branches to break on both evergreen and deciduous plants.
Ice coated sidewalks, driveways and branches various times this winter. Thick accumulations of ice formed on branches which couldn’t handle the added weight and broke. Attempts by gardeners to lessen the weight by knocking off the ice layer only caused more damage to the plant by removing overwintering buds.
Excessive snow on arborvitae have caused some to bend and break due to the extra weight. Some branches may not have completely broken off but have been bent downward and may not return to their normal positions resulting in deformed plants. A layer of snow has its benefits, though, as an insulator. Deep into the soil profile, soil temperatures may become very cold, causing injury to plant roots in the absence of an insulating cover of snow. When a plant’s root system is damaged, leaves may emerge from the plant but may dry up and die due to the lack of a functional root system to supply water to them. In some instances, cold injury to root systems results in death of the affected plant.