As winter approaches, insects come up with a variety of strategies to survive the freezing temperatures of the season. Most head for some cover (including our homes!) where they will be partially insulated from the most severe effects of the weather.
But more fundamentally, insects undergo body changes that favor their cold-hardiness. One of the most common changes is that they produce glycerol in their blood -- a natural anti-freeze. Insects also can partially dehydrate their cells which further lowers their freezing point.
Furthermore, to ensure that the insect does not emerge prematurely during a winter warm spell, it goes into a state of semi-dormancy, known as diapause. Diapause can only be broken when the proper environmental signal is received, such as a critical day length or a minimum period of chilling. until the diapause signal occurs, insects remain dormant and inactive.
Photo: Connor Sedbrook
© CSU/Denver County Extension Master Gardener 2010
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Date last revised: 01/05/2010