Arbor Day is in the Spring, But We Work on Trees in the Winter Too

Photo Credit: LeRoy Oaks by @thereal_john.e on Instagram

by Jeremy Craft, Public Works Division Manager & Certified Arborist , jcraft@stcharlesil.gov

It’s spring now and everyone’s thoughts turn to getting outside to work on their yards. But the St. Charles Public Services Forestry Staff has been busy all winter.

This winter, we concentrated on pruning oak trees, primarily in the southwest section of town.  Performing routine pruning maintenance on our oaks is essential to promote proper growth and ensure the long term health of the trees. To allow the City’s oak tree population to thrive, it is necessary to trim these trees during the dormant season.

Winter tree care allows us to fortify and strengthen well-established structural limbs, and to mitigate hazards that may be particularly threatening when combined with snow and ice conditions present in the winter, such as the removal of dead or broken limbs. In addition, trimming in the winter allows the forestry staff the ability to review the trees without the leaves, which makes it easier to assess the overall health of the tree.

Our team began trimming oaks specifically in early November and finished in March. Completing our trimming efforts within this timeframe is critically important to the long-term success of the community’s oak trees. The primary reason pruning is performed during the colder months is to prevent the spread of Oak Wilt, which is a fungal disease that invades the water conducting tissues and causes the tree to shut down its own vessels. This condition prevents the normal flow of water throughout the tree, which results in the wilting of the tree’s foliage, and frequently leads to the death of the tree. During the winter, insects which carry the deadly fungal spores are dormant and less likely to transmit via air or pruning utensils.

We will continue this pruning process in upcoming winter seasons and hope this effort will sustain and add to the vitality of the St. Charles oak tree population. One great tip for homeowners to apply during the winter months to their private Oaks is to place two to four inches of organic mulch around the tree(s). The mulch placed three to six inches away from the trunk will help the tree(s) retain water, reduce temperature extremes, and act like a blanket to provide the roots a little extra winter protection.