Damage caused by the emerald ash borer, a highly destructive beetle native to Asia, is visible across several U.S. states and large parts of Quebec and Ontario. The insect, first detected in Canada in 2002, typically kills 99% of ash trees in a given area within six years and has caused the destruction of tens of millions of trees. Its spread has also resulted in hefty bills for the treatment or removal of countless ash trees.
As chainsaws slice through dead logs, governments are trying ways to stop the pest in its tracks, such as culling healthy trees and altering landscapes. Now, Frithjof Lutscher, a professor at the University of Ottawa’s Department of Mathematics and Statistics, has used math to investigate the effectiveness of such measures, and has discovered that some might actually be doing more harm than good.