Using dendrochronology to model hemlock woolly adelgid effects on eastern hemlock growth and vulnerability

This study examined the relationship between eastern hemlock (Tsuga canadensis (L.) Carr.) crown condition and changes in radial growth associated with infestation by hemlock woolly adelgid Adelges tsugae (Homoptera: Adelgidae) (HWA). Tree-ring chronologies of eastern hemlock were used to develop a binomial decline index based on three consecutive years of below average growth. Radial growth decline was modeled, using logistic regression, as a function of an extensive array of tree, crown, and site variables that were collected over an 11 year period in Delaware Water Gap National Recreation Area.