Some bugs are cool
During the heat of summer, the pesky bugs get all the attention. Japanese beetles already are devouring roses, and buffalo gnats have enjoyed a monthlong heyday.
And to add insult to injury, bug sprays don’t seem to deter them much at all.
But some insects are cool — and the vast majority are beneficial. Most can be found pollinating crops, breaking down waste, keeping certain plants in check and providing a valuable food source for birds.
Some are simply stunning to see.
All live for just a short window of time while the weather stays warm.
Tim Cashatt of the Illinois State Museum says that state is home to 13,000-14,000 species of insects.
“And that’s probably a very conservative estimate,” he says. “And they all have a purpose in life.”
Even some insects considered pests — like the hated yellow jacket that spoils fall picnics — still are beneficial because of their role as pollinators.
“Lots of wasps and beetles end up spreading pollen inadvertently because they are going between plants,” says Cashatt.
Last week at Lincoln Memorial Garden & Nature Center on the shore of Lake Springfield, an unusual-looking moth with partially transparent wings hovered over wildflowers, looking for a moment like a hummingbird.
“They are a day-flying moth, and they hover just like a hummingbird,” says Phil Nixon, an entomologist with the University of Illinois Extension. “The clearwing moths mimic wasps, hummingbirds and bumble bees so the birds will leave them alone.
“And in the process of gathering nectar they pollinate plants.”
Nixon says people call all the time to report them, sometimes sending pictures.
“They are an aberration,” he says.
Sometimes, pollinating insects aren’t missed until they are gone. Nixon points to the concern over the loss of honeybees to colony collapse disorder — a phenomenon in some parts of the country in which bees fly away from the hive and never return.
Scientists are trying to figure out why whole colonies of bees simply fall apart. Honeybees play a critical role in pollinating crops, especially fruits and vegetables.
“Honeybees are not native,” he says. “But they are needed when we plant huge monocultures (of a single crop).”
Native pollinators can’t pick up all the slack if honeybees aren’t available.
“But native carpenter bees, bumble bees, flies, wasps, butterflies and moths all help to keep things running right and result in many of our natural areas continuing to exist.
“And in many instances, they stepped into the gap and helped pollinate our gardens.”
Native plants and insects often rely on each other.
The prairie cicada feeds on the roots of the Silphiums, a handful of extremely tall-growing prairie wildflowers. Prairie cicadas are only found in remnant prairies, such as those along abandoned railroad lines or in pioneer cemeteries.
The role insects play in helping preserve Illinois’ remaining natural areas often is overlooked. But people can help by landscaping with native plants whenever possible.
“That’s a tremendous service that is done, and many times we can help keep those native insects going by having some natural areas around that may contain some of the host plants that their larvae feed on,” says Nixon.
Cashatt says people have a habit of throwing nature out of equilibrium.
“Until we got in the way and started introducing plants from other places and turned others into row crops, things worked pretty smoothly,” he says.
Insects can become pests when their food plants become dominant on the landscape.
“Populations build according to their food plant,” he says. “And all of a sudden, you’ve got a lot of pests out there in vast numbers.”
A diverse prairie with 300 species of plants won’t be decimated if one plant comes down with a disease or is attacked by an insect pest.
But vast fields with a single crop are bound to multiply associated pests, requiring more cost and effort to fight them.
Nixon says people naturally are drawn to charismatic insects, like the praying mantis, which “can turn its head like a human can.”
“From what we actually know, there are about 800,000 to 1 million species worldwide,” says Cashatt.
Scientists still are exploring the world at our feet and over our heads.
That doesn’t count all of the insects living in the rainforest, especially in the forest canopy, that haven’t even been identified yet, says Cashatt.
“They are finding new species all the time.”
And the prairie state has plenty of bugs to go around — both friendly and the pesky.
“You are looking at thousands of species of insects in Illinois,” says Nixon. “It’s all an estimate, because we really don’t know how many species are in Illinois.”
State Journal-Register writer Chris Young can be reached at 788-1528.