It’s a hard day’s night for sidewalk beetles
Staff writer
Entomophobes — people scared of insects — probably shouldn’t be taking nighttime strolls anytime soon.
Nocturnal, red-brown bugs that flock to artificial light sources are abundant on porches and sidewalks across the Flint Hills. Walk down Marion’s Main St. on a warm night, and you’ll come across a few under every lamppost. Stray cats swat them around, and nightwalkers tip-toe around their shells.
The little critters are beetles in the Phyllophaga genus.
They are commonly referred to as June bugs, June beetles, or May beetles for the time of year that they emerge.
Some might think of a shiny green beetle when they think of a June bug. This is Cotinis nitida, a larger insect with a few similarities (both fly in a wobbly fashion and emerge at the same time of year) and a few differences (Cotinis nitida is a different color, not nocturnal, and sticks to grassy areas more often).
Raymond Cloyd, an entomology professor at Kansas State University, refers to Phyllophaga beetles as “May beetles” and Cotinis nitida as “June beetles.”
“That’s the problem with common names,” Cloyd said. “They don’t really mean anything.”
Wikipedia lists seven different beetles that are referred to as June bugs, from the stripy Polyphylla decemlineata to the hairy Amphimallon solstitiale.
But Phyllophaga are the beetles most common to the county.
Phyllophaga larvae, known as grubworms or grubs, feed on roots and decompose nutrients underground.
The grubs occasionally do damage to garden plants such as lettuce, raspberries, and strawberries. They serve as a food source for skunks, raccoons, and possums.
“They stay in the soil for about two years, and then in the third year, they’ll come out as adults,” Cloyd said.
Adult Phyllophaga beetles feed on a variety of leaves — oak, hickory, walnut, birch, poplar, and more.
Attracted to bright light, they tend to be found on sidewalks because they somewhat comically fly into lampposts and fall to the ground, Cloyd said.
The Phyllophaga population has indeed been high this summer, Cloyd said. In fact, the beetles are causing more damage to local trees than ever.
“This is the first year we’ve seen extensive damage caused by adults,” he said. “The numbers have been great, possibly due to environmental conditions in the soil.”
The trees will get a respite later this month. Females will go underground to lay eggs, adults will die off, and a new Phyllophaga cycle will begin.
Phyllophaga are harmless to people, but if you want to keep them away from your home, keep your porch light off and use screens on your windows.
“Eventually they’ll go away,” Cloyd said. “They’re not a major problem unless they’re feeding on your oaks or your other plants. I would just let them go through their cycle.”