Emerald Ash Borer

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August 11, 2015- Over the next five weeks, two wasp species that parasitize EAB larvae will be released in Boulder.


Emerald Ash Borer (EAB) was found in Boulder, CO, in September 2013. As a non-native insect, EAB lacks predators to keep it in check. EAB only attacks ash trees in the genus Fraxinus (so mountain ash are not susceptible). 

Approximately 15% of the trees that make up Colorado's urban forest are ash. There are an estimated 98,000 in the city of Boulder alone. The Denver Metro area has an estimated 1.45 million ash trees. EAB is responsible for the death of millions of ash trees in the United States.

Help protect Colorado's ash trees! Don't move firewood, and consider chemical treatments to protect high-value ash trees within or near the EAB Quarantine area. 

The Colorado Emerald Ash Borer Response Team