The pathology of Sitka spruce in northern Britain

Abstract

SynopsisAn account of the pathology of Sitka spruce in northern Britain is given based on enquiries dealt with by the Pathology Branch of the Forestry Commission Research Division in the last fifteen years. Sitka spruce occupies the major proportion of our forest estate but has given rise to only 15% of enquiries concerning tree damage. The most frequently diagnosed injuries have been those due to frost and to root diseases caused by Heterobasidion annosum and Armillaria spp. Two other root pathogens, Rhizina undulata and Phaeolus schweinitzii, and two needle pathogens, Lophodermiun piceae and Rhizosphaera kalkhoffii, have also been recorded in Sitka spruce plantations as have several wound-infecting stem decay fungi. Only five other fungal diseases, those caused by Botrytis cinerea, Phytophthora citricola, Helicobasidium purpureum, Sirococcus strobilinus and Pythium spp. have been recorded, all in nurseries.