Flicker of fireflies inspires beetle mania

Environmental conditions that have favored so many insects this year have also encouraged the beetle, resulting in sparkling clouds of lightning bugs over lawns and swarms of blister beetles over soybean fields.

Springtime brought scads of good ladybugs – which, along with lightning bugs, are actually beetles – and summertime is ushering in the bad Japanese beetle.

“Insects are completely, 100 percent controlled by their environment,” K-State entomologist Jeff Whitworth said, and that’s why, for example, you probably have seen more fireflies this summer.

“There’s more humidity; people notice them a little more,” Whitworth said. “There’s quite a few of them around, so it’s kind of neat.”

Not all beetles are present at the same time, so different conditions can be at play. Sedgwick County extension agent Rebecca McMahon noticed tons of ladybugs in the spring, because they had a lot to eat. “We had a lot of aphids overwinter, so they were fat and happy,” she said of the ladybugs.

Lightning bugs

With the lightning bugs, “I would expect them to increase over the next couple years,” retired K-State entomologist Larry Buschman said. This is because the bioluminescent insects need constant moisture, and rains have been following the drought, said Buschman, who now lives in Colorado and studies fireflies.

“These insects have a one- or two-year life cycle, so the response to the good weather conditions will be a year or two later. They are responding to the good weather conditions.”

The lightning bugs’ blinking lights start to peter out by this point in the summer. A decrease in their numbers overall has led to such things as firefly parks in China, where they’ve otherwise disappeared from the cities. A loss of wild, undisturbed habitat is one reason for their decline, Buschman said.

And “you want a habitat that does not dry out completely,” Buschman said. “There has to be moisture available permanently; otherwise, they die off.”

In addition to drought, a proliferation of water wells that lower the water table and dry up springs and marshes has cut into the number of fireflies, Buschman writes in his “Field Guide to Western North American Fireflies,” which can be found on K-State’s entomology website (entomology.k-state.edu).

If people want to encourage lightning bugs, they should first avoid using grub-control pesticides on their lawns, he said. Grubs are larvae of beetles, so poison directed at them hurts lightning bugs more than other kinds of pesticides, he said.

And while a couple of species of fireflies can live in suburban lawns, leaving some higher-mowed areas, especially if you live near a creek or river, will help them, too, he said.

And a note for the children: If they insist on catching fireflies, place a slice of apple in a jar, give the lightning bugs a bit of ventilation and release them in the same area on the same night, not keeping them for any length of time, Buschman said.

Swarms in fields

If the lightning bugs are taking their bow for the summer, other beetles are causing a ruckus, especially for farmers.

“Blister beetles are swarming in the hundreds and thousands, mostly in soybeans and alfalfa,” Whitworth said. “I’ve gotten several calls.” Fortunately, the sight of the swarms is worse than the damage they do, which isn’t much, he said.

Back in the city, you might literally run into a green June beetle. According to another K-State entomologist, Raymond Cloyd, writing on the K-State blog this week, the beetles, which buzz like bumblebees, dive-bomb turfgrass, looking for a mate in the lawn. They can bump into people in the process, Cloyd writes.

In the garden, Japanese beetles are just starting to show up in Wichita and are not much of a menace – yet, McMahon said.

The Japanese imports are one of the most destructive plant-eating insects, Cloyd writes. They go after plants that are in the sun all day – including trees, shrubs, vines, annuals and perennials, especially roses – eating flowers and flower buds but also often leaving leaves looking lacy or skeletonized.

Among the ways to curtail them, according to Cloyd: Keep plants healthy; remove weeds such as smartweed that they also like; pick them off in the morning if you see them on plants. They are about half an inch long and are a metallic green with coppery-brown wing covers. An easy way to collect them is to carry a wide-mouth jar or bucket with some soapy water or rubbing alcohol in it, and merely touch the beetle, which will cause it to fall into the liquid.

Repeat applications of contact insecticides can help kill adult Japanese beetles, according to Cloyd, but since most of those also kill beneficial bugs, secondary infestations can happen. Also, if using an insecticides, spray only in the early morning or late evening to avoid killing pollinators. Systemic insecticides generally aren’t effective. Options include carbaryl (Sevin) and several pyrethroid-based insecticides including those containing bifenthrin or cyfluthrin as the active ingredient, according to Cloyd.

This story was originally published July 12, 2016 at 5:52 PM with the headline "Flicker of fireflies inspires beetle mania."