Green invasive beetles devour plants across Kansas

TOPEKA (KSNT) – Summer warmth is bringing with it a swarm of bright-green beetles that come with a big appetite for Kansas crops and gardens.

27 News got in touch with Professor Raymond Cloyd at Kansas State University this week to learn more about the dangers posed by invasive Japanese beetles in the Sunflower State. The insects are emerging from the ground with the arrival of summer and are dining on many of the state’s native plants and some of its cash crops.

“They are a pest,” Cloyd said.

Cloyd said the beetles have a big appetite and once they come out of the soil they start to look for plants to eat. He said people will start to notice them flying around or eating different plants in the summer months before they disappear again with the arrival of fall.

“They have an annual life cycle,” Cloyd said. “Most of their life is in the soil.”

Biologists have recorded the beetles feeding on more than 300 different types of plants such as Virginia creeper, linden, crabapple, roses, American elm and willow along with crops like corn and soybeans. The beetles consume the leaves, leaving behind skeletal or lacelike remains, and work their way through the entirety of the plant before moving on.

Cloyd said that one of the worst aspects of the beetles is that they will be more attracted to plants which have already been visited by other beetles, causing extensive damage. He said this also occurs whenever people try to use insect traps that draw in beetles which can lead to more problems, especially in urban areas, as the beetles arrive in greater and greater numbers.

“We do not recommend Japanese beetle traps because they’ll attract more of them,” Cloyd said.

Cloyd said the beetles spend the rest of their lives as grubs beneath the ground where they feed on the roots of plants or turf grass. The small, white larvae appear in the shape of a ‘C’ and move about in the soil depending on its temperature, retreating deeper below ground as it gets colder outside.

“When an insect is out for three months, they’re gonna eat everything they can,” Cloyd said.

People wanting to fight back against the beetles can use insecticides on plants during the summer or apply insecticides on the ground to kill the grubs before they emerge. Cloyd said people can also remove beetles by hand and putting them into soapy water or rubbing alcohol. Removing the beetles by hand can reduce the effect of the insects attracting others to the same area as well.

“Some people catch them and feed them to geese and ducks,” Cloyd said.

You can learn more about invasive Japanese beetles by heading to K-State’s website. You can also check out the document below for more tips on getting rid of the insects.

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