Cold Bugs Are Not Active This Winter
By Ray Novitske, Fairfax Master Gardener
Insects have several methods for surviving our cold winters. Some species survive as eggs, some look for warmth and protection, others put up with the cold, while others “hibernate” so to speak. If we understand these methods, we can more effectively control insects when they emerge in the spring.
The best way to avoid the winter is to look for warm weather, or warmer temperatures. We are all familiar with the monarch butterflies that fly south to spend winters in Mexico. Lady beetles and stink bugs will find warmer temperatures in the cracks and holes in our heated homes and attics. Certain bees will huddle together in a mass or “aggregate” in their hives to conserve heat.
Finally, some insects go into a semi-dormant state or “diapause” for the winter. In cold weather, the insects’ development, reproduction, and feeding cease for months. They live off the fat and energy stores built up from the previous season. The trigger to initiate this state can be environmental, such as day length, temperature, or both. The same environmental factors then trigger the reemergence in warmer weather. An abnormal fall, winter, or spring, such as a late or early arrival, can cause problems for these insects.
Be observant of the winter and know the signs to help you prepare for the next season’s pests. Little snow cover along with several severe fluctuating temperature swings during the winter can reduce insects that overwinter in the ground or under leaf litter. An early thaw and then quick freeze can make survival difficult. Slowly emerging plants used as food sources can hurt the insects that depend on them. Know how the winter affects your most troublesome pests, and be prepared for the spring.
• Where Do Insects Go in the Winter, Smithsonian Institution
• How Do Insects Survive Winter, Sandra Mason, University of Illinois Extension
• How Insects Survive Cold: The Potential Effect of a Mild Winter, Chris DiFonzo, Fred Springborn,
Megan Chludzinski, Michigan State University Extension
• Where Do Insects Go in Winter?, Michigan State University Extension
• How Do Insects Overwinter in Colorado, Extension.org