Red Pine Pocket Mortality - Introduction

Red pine pocket mortality, caused by a complex of insects and the fungi Leptographium terrebrantis and L. procerum was first identified in Wisconsin in 1975. National distribution of this syndrome is unknown. Thinned, plantation-grown red pines between the ages of 30-45 are most likely to show symptoms of this syndrome.

Red pine pocket mortality was observed in 109 of 157 red pine plantations in a 2002 survey. The number of pockets per plantation varied between 0-8. Red pine is the only species that has shown symptoms of this syndrome.

Site Factors/Stand History

Studies attempting to identify site factors associated with red pine pocket mortality are ongoing. Red pine pocket mortality is a disease of plantation-grown red pine. Red pine pockets are more common in stands that have been thinned than in unthinned stands; root grafts provide a pathway for Leptographium to move from tree to tree.