Of the trees that haven't been destroyed, he said 85% are "heavily infested by one or more long-horned beetles" that bore into the wood of adult boswellia and eat them from the inside.
But encroaching agriculture and insects threaten to kill off most of the region's boswellia within the next 50 years, according to a study published this week in the Journal of Applied Ecology by a team of Dutch and Ethiopian ecologists.