Incidence of butt rot in a tree species experiment in northern Denmark

摘要

The susceptibility to infections by Heterobasidion annosum was examined in a 28-yr-old tree species experiment in northern Jutland, Denmark. Silver fir (Abies alba), Caucasian fir (Abies nordmanniana), grand fir (Abies grandis), noble fir (Abies procera), Japanese larch (Larix kaempferi [syn. L. leptolepis]), Norway spruce (Picea abies), Sitka spruce (Picea sitchensis) and Douglas fir (Pseudotsuga menziesii) were planted after shelterwood felling of a mountain pine (Pinus uncinata) stand that had been infected by H. annosum. Douglas fir and noble fir showed the greatest mortality due to H. annosum during the first 5 yr after planting. At first thinning the highest incidences of butt rot were recorded in noble fir, Japanese larch and Sitka spruce,with 44, 43 and 36% of the thinned trees infected, respectively. Silver fir and Caucasian fir were almost free from infections. Maximum extension of H. annosum rot columns were in Japanese larch (18 dm). Heterobasidion annosum was the most important decay causing fungus found. Mating tests assigned all isolated strains of H. annosum to the P-intersterility group.