Where did the Japanese Beetles come from?

GRAND JUNCTION, Colo. (KKCO) - We received an email shortly after airing our first story on the Japanese beetle infestation. A viewer was concerned that a local nursery had something to do with the outbreak.

A map of beetles shows Bookcliff Gardens directly in the hot spot. Tyler Bertroch, operations manager for Bookcliff Gardens, wants to make it clear they don’t know where the beetles came from.

“In our seminar, obviously, we saw the outbreak diagram and it was all around us. We knew we were talking with the CDA. We don’t know where it came from actually,” said Bertroch.

The noxious weed and pest management coordinator told us that these beetles have inhabited Mesa County since 2002.

“Mesa County has been monitoring and trapping for Japanese beetles for the past 20 years, we detected a reproducing population,” said Duncan Dearduff, Noxious Weed and Pest Management Coordinator for Mesa County.

The reproducing population may be responsible for the current infestation. But gardeners like Bertroch think the outbreak might have started a different way.

“It could have been a rogue landscaper not registered with the Colorado Department of Agriculture that went over and got some sod came back,” said Bertroch. “There’s a lot of development around here. That’s the hunch of where we think it came from.”

Before plants are shipped to Bookcliff Gardens, they go through an extensive check point. They are sprayed with pesticides and other bug killing products to eliminate larva.

When they arrive here, plants are checked for signs of bugs and sprayed again in the spring.

“Mid-April, and it’s about a two-week interval spray,” said Bertroch. “Generally, we don’t have any problems.”

He says Japanese beetles start off in grass. He advises homeowners to be proactive by spraying insecticides around their lawn by mid-April and reapply in June.

We will keep you updated on this developing story.

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