"This chapter describes when degree-days and plant phenology can be used effectively to predict insect emergence and time pest management activities." http://www.entomology.umn.edu/cues/Web/049DegreeDays.pdf
"In summary, calculating degree-days can be an effective tool for predicting insect emergence. Biological calendars consisting of the flowering sequence of ornamental trees and shrubs can also be used quite accurately to track degree-day accumulation and predict pest activity. The use of such indicators for timing pest activity holds tremendous potential for improving the effectiveness of IPM programs in nurseries and landscapes."
