Field evaluation of a native fungus for control of melaleuca (Melaleuca quinquenervia) in southern Florida

A native fungus, Botryosphaeria ribis, was evaluated under field conditions to determine its potential to control melaleuca. Applications consisted of either wound inoculations of trees with B. ribis or fresh stump treatments with B. ribis alone or mixed with imazapyr herbicide. There was no mortality among nondefoliated trees inoculated with B. ribis. Mortality of B. ribis-inoculated trees was increased by three complete defoliation cycles. Defoliated trees inoculated with isolate BR-5 exhibited 100% mortality compared to 17% for defolated but noninoculated trees. Wounds inoculated with B. ribis during winter produced longer cankers than did noninoculated wounds. Stump regrowth reduction by treatment with B. ribis alone was less effective than treatment with imazapyr alone. Mixtures of B. ribis with imazapyr or imazapyr alone at comparable concentrations did not differ in stump regrowth control.