The prediction of Crumenulopsis sororia (Karst.) Groves. Incidence on lodgepole pine (Pinus contorta Dougl.) using multiple regression techniques.

Investigations of the etiology and epidemiology of pathogenic diseases can be genetically divided into several stages. Initially, attention is concentrated upon describing and quantifying the disease symptoms themselves, so that new outbreak may be recognized easily by other workers. The second phase focuses attention upon the environmental factors responsible for the optimum spread of the pathogen and for the development of the disease. Initially, a knowledge of these factors is used in order to predict the likelihood of future disease outbreaks. This approach has been used with considerable success on many serious plant diseases.