The City of Denver was put on red alert in June, when the emerald ash borer was identified in the city for the first time, following more than a decade of warnings.
The emerald ash borer is an invasive species of beetle native to north-eastern Asia. It is considered the most destructive forest pest in United States history, with its larvae having killed tens of millions of ash trees by tunneling through the wood and damaging the tree’s ability to transport nutrients and water.
That is a big problem for the Mile High City. There are 1.45 million ash trees in the Denver metro area and 330,000 within city limits, accounting for around one in every six trees in Denver, according to Denver Parks & Recreation…