COLUMBIA — A handsome but pesky creature has made its way to Columbia, and entomologists say it is here to stay.
The Japanese beetle arrived in mid-Missouri in June and began feasting on fruit trees, roses and other plants. Although they have only been in the vicinity for a little more than a decade, they can devastate about 300 species of plants in the urban landscape.
Adult beetles are about a half-inch long with a green and copper metallic body that looks like armor.
They live for most of one year, developing into white larvae through winter and maturing during the spring.
The bugs emerge the first week of June and stay until mid-August, with the highest number of beetles present between July 10 and 20. After that, the beetles gradually die off.
Japanese beetles are expected to grow in population through the next five to seven years, according to MU entomologist Wayne Bailey. He said he caught more than 1,600 beetles in three days with a single trap.
The beetles were considered an established population in Boone County around the year 2000, making their way across the state from the St. Louis area, MU entomologist Ben Puttler said.
They are attracted to plants, shrubs and sweet-smelling fruit trees. Their damage can be identified by a lacy, net-like pattern on the leaves.
The beetles are active on warm, sunny days and work in groups.
Puttler said they are most attracted to roses and linden trees in Boone County. Some linden trees have been damaged on the MU campus, blemished by a browning effect on the foliage. They are also attracted to grapes, apples and peaches.
For farmers and Columbia residents, protecting fruit trees and plants may be more of a challenge than they expect.
“Japanese beetles are annual, and they are so mobile that even if you treat your yard, they might migrate from a neighbor’s yard,” Puttler said.
There are several ways to try and get rid of them.
Bailey suggests staple insecticides such as Sevin dust.
"Sevin is probably one of the best because it's readily available and relatively safe to most everything around," he said.
Other methods include handpicking the beetles from the leaves, planting herbs such as garlic and chives near the garden and using traps.