Emerald Ash Borer

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June 1, 2015 - EAB adults now emerging in the City of Boulder. Look for them feeding on ash leaves..............June 10, 2015 - Over the next 6 weeks, Oobius agrilli, a stingless wasp, used for biological control of Emerald Ash Borer, are to be released on the University of Colorado, Boulder, campus................June 16, 2015 - Over 300 EAB traps have been deployed around the State of Colorado for monitoring and detection purposes.................


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