Discoloration and decay associated with hardware installation in trees

"A sample of 20 bolts of wood that had hardware previously installed was collected from arborists throughout the northeastern United States. The samples received came from trees regarded as good compartmentalizers. Simple measurements and visual analysis indicate that decay and discoloration directly attributable to hardware installation appear not to be as severe as expected (even after 37 years in one sample)." [UMN]

"Tree support systems have been used for many years to help reduce the risk of tree failure due to weak and split crotches and from cracks in branches and trunks. Because any wound that breaks the bark of a tree initiates the decay and compartmentalization processes, new tree support systems have been designed to eliminate the need to drill holes into a tree during installation. Recent research suggests that the new systems do not injure tree parts as much as drilling holes, because drilling wounds the tree. A sample of 20 bolts of wood that had hardware previously installed was collected from arborists throughout the northeastern United States. The samples received came from trees regarded as good compartmentalizers. Simple measurements and visual analysis indicate that decay and discoloration directly attributable to hardware installation appear not to be as severe as expected (even after 37 years in one sample). More quantitative research into physiological and mechanical aspects of tree support systems is needed to assess each system’s utility for arborists." [Abstract]