Abstract
Stand structure and vigor variables were used to develop a model for predicting the development of a Dendroctonusponderosae Hopk. outbreak in climax Pinuscontorta Dougl. ex Loud. var. murrayana Grev. and Balf. stands in south central Oregon. Stepwise discriminant analysis indicated the significant predictor variables were quadratic mean diameter and the number of rings in the outermost centimetre of radial growth at breast height (p = 0.00001, canonical correlation coefficient = 0.77235). Ninety-three percent of the stands were correctly classified into their appropriate groups (attacked versus unattacked). None of the five indices of competition tested (i) Waring and Pitman's tree vigor index, (ii) Mahoney's periodic growth ratio, (iii) Krajicek's crown competition factor, (iv) Hegyi's competition index, and (v) Curtis's stand density index) were significant discriminators.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call