Decay of fire-damaged lodgepole pine in south-central Oregon

Abstract

About 150 lodgepole pines, Pinus contorta var. murrayana (Grev. and Balf.), growing in topoedaphic climax stands of south-central Oregon, were identified as having survived fires that occurred over a period from 1839 to 1982. All fires were natural wildfires, except for prescribed burns of 1976, 1980 and 1982. The trees were sampled for bole and root damage to investigate fungal colonization patterns, establishment of decay columns, and diameter growth. Fire-damaged roots were the principal entry point for decay fungi in fire damaged trees. White-rot fungal species and fungi imperfecti rapidly colonized fire-killed root tissues within 2 years after a fire. These fungi were later displaced by slower growing brown-rot Basidiomycetes that eventually extended into the boles of infected trees. Trees with butt rot, principally caused by Poria asiatica, grew significantly slower than uninfected trees.