Impact Of Pine Stem Rusts Of Hard Pines In Alberta And The Northwest Territories PDF Download

Sweetfern rust, caused by the fungus Cronartium comptoniae Arth., is a common disease of two- and three-needled pines. It occurs in the East, throughout the United States and Canada, and in the West from Alaska to California and is probably transcontinental. This fungus causes cankers on pines and often kills trees. If an infected tree survives, the part attacked frequently becomes so malformed that it must be culled (fig. 1). Decay fungi often enter the stem through these cankered surfaces and cause heart rot.