New research predicts which trees are at greatest risk of beetle outbreak

An early-warning system developed by researchers could help forest managers in Europe predict which trees are at greatest risk of bark-beetle infestation. The study looked at the probability of bark-beetle outbreaks on two important conifer-tree species in Slovenia: the Norway spruce (Picea abies) and silver fir (Abies alba). It found that high temperatures, and extreme weather linked to climate change -- including droughts and ice storms -- weakened trees, making them more vulnerable to attack by bark beetles.