DENVER (AP/CBS4) – Agriculture officials say an invasive insect responsible for the death of tens of millions of ash trees in almost two dozen states has been detected for the first time in Colorado.

The Colorado Department of Agriculture says the emerald ash borer, a green metallic beetle, was found by Boulder forestry staff Monday. The beetle, originally from Asia, was first detected in North America in 2002 in southeastern Michigan and has since killed more than 50 million ash trees across the country. It has now been detected in 21 states — Colorado being the westernmost.

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“The confirmation of these specimens as emerald ash borer marks the western-most occurrence of this invasive pest in North America,” said Patrick McPherren, USDA State Plant Health Director in Colorado. “To date Colorado is the fourth State to detect EAB in 2013.”

“The first step will be to determine how widespread its presence is,” said CDA’s Plant Inspection Division Director, Mitch Yergert. “We have a plan in place to quickly respond in order to protect Colorado’s ash trees.”

The emerald ash borer lays eggs under the bark, and when they hatch it infects the tree. Once that happens it’s almost impossible to stop.

“I think it’s probably one of, if not one of the worst invasive species the U.S. has ever seen,” John Kaltenbach with the Colorado Department of Agriculture said.

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Kaltenbach and his team are surveying areas near where the emerald ash borer infected two ash trees so far in Boulder.

Colorado’s agriculture department says ash trees thrive in Colorado, with an estimated 98,000 in the city of Boulder alone. The Denver metro area has about 1.45 million ash trees.

“The worse that can happen is we lose 1/5th of all our trees in the metro areas. So trees along the street, in our parks, neighborhoods, in our own backyards we can lose because of this insect,” Kaltenbach said.

Additional Information From Colorado Department Of Agriculture

If you think you have EAB in your ash trees, or if you have any questions or concerns, or would like additional information, please contact the Colorado Department of Agriculture at 888-248-5535 or email

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