BIOLOGICAL-CONTROL OF RED ALDER USING STEM TREATMENTS WITH THE FUNGUS CHONDROSTEREUM-PURPUREUM

Young red alder (Alnus rubra Bong.) trees were frilled at breast height and the frills inoculated with cultures of Chondrostereum purpureum (Pers. ex Fr.) Pouzar in April, June, October, and in April of the following year. Over the ensuing 4 years, healing of the frills was less and tree mortality greater in trees inoculated with C. purpureum than in the uninoculated controls in the June and October treatments. Projected mortality for trees inoculated in June and October exceeded 80%. Among inoculation treatments, there was a strong correlation (r = 0.816) between percent tree mortality and the percentage of trees on which C. purpureum basidiocarps were recorded. It was concluded that summer or autumn inoculation with C. purpureum can be more effective in controlling red alder than frilling alone, and widens the treatment window for manual control.