What do degree day measures indicate?

Degree day measures are used primarily to assess insect growth and development in relation to temperature. They are calculated based on daily temperatures and help predict the life stages of insects, such as when they will hatch, pupate, or reach maturity. This concept is rooted in the understanding that insects develop at different rates depending on the temperature, and accumulating 'degree days' helps to time pest management strategies effectively.

Understanding the number of degree days can assist horticulturists and farmers in planning when to apply treatments for pests or diseases, making it a crucial aspect of Integrated Pest Management (IPM). By focusing on the temperature-dependent development of insects, practitioners can anticipate their life cycles and manage them more effectively, thus minimizing crop damage and enhancing plant health.