Evaluation of diseases within selected stands on the Priest River Experimental Forest, Idaho

Three stands along Benton Creek within the Priest River Experimental Forest,\ud Idaho, were surveyed for diseases using previously established timber inventory\ud plots and sample trees. These surveys provided information to aid in formation of silvicultural prescriptions by CEFES (Continuing Education in\ud Forest Ecology and Silviculture) students. Diseases were quantified at the\ud stand level using the Northern Region's Insect and Disease Damage Survey\ud System (INDIDS). The evaluation showed that about 10 percent of the trees\ud examined had some noticeable disease. Mortality associated with root\ud disease was found throughout the stands. Based on previous work in the area, we believe most trees are infected with root pathogens but lacked\ud symptoms. The major pathogenic fungi associated with root diseases were\ud Phaeolus schweinitzii and Armillaria mellea. Butt and stem decays were also\ud prevalent, especially Phellinus pini on western white pine and western\ud larch. Management implications and strategies are discussed