A Trill a Minute as 13-year Cicadas Emerge
Jun 02, 2011
If you think your teenagers are noisy, you should be hanging out at my house. Last week millions of trilling 13 year old cicadas emerged after a long nap.
These bug-eyed boys and girls tunneled out of the soil, spread their wings and are now busy singing up a storm—not to mention unabashedly making out like mad in the bushes, tree branches and almost anywhere you look (or try not to look).
These are periodical cicadas or more officially known as Marlatt’s XIX or the Great Southern Brood. Decatur, where I live in central Illinois, is on the northern edge of their geographic range.
Don’t get confused. We have some cicadas each year. Annual cicadas with their green bodies and black eyes tend to show up each August and thus, are often called “dog day” cicadas.
Periodical cicadas are smaller than the annual variety. They have bright red eyes and orange-veined wings and they come in volume—both numbers and noise.
University of Illinois entomologist Phil Nixon says cicadas don’t cause crop damage. Cicadas are not locusts. They sip plant sap, but generally don’t damage plants. Farmers may see them along the edges of fields close to established timberland. They aren’t very good flyers, so the populations don’t spread very far from these established treed areas.
I first noticed the nymphs in the soil this spring when I moved some old bricks. The local raccoons had apparently been reading the extension alerts because the masked varmits rolled the sod back and turned part of the yard into the equivalent of a hog lot as they rooted to dine on nymphs.
About a week ago, the nymphs began to emerge from the soil. My flower beds and yards are covered with small round holes that look like the high school football team took several jogs through the area with cleats. Every morning more of these holes appear and with them, more cicadas.
This is an adult emergence. The eggs hatched 13 years ago and have been lounging (and molting) beneath ground until they became full fledged teenagers. Now Mother Nature has given them permission to demonstrate their independence. Think of it as the equivalent of your child finally leaving the basement upon the realization that dedication to sleep or Nintendo might not be the best way to cross paths with members of the opposite sex.
When fully grown, the nymphs emerge from the soil, climb a tree, building, or other upright object, and shed the exoskeleton that protected their body and wings while tunneling up through the soil. By pumping body fluids to the thorax area behind the head, the thorax swells and splits the exoskeleton. This allows the adult to emerge. Once free, fluids are pumped into their wings causing them to unfold and expand. The cicadas are nearly white when they first emerge, but it doesn’t take long before the body has hardened into a red eyed wonder with orange waxy wings.
I have tinnitus—an ear ringing issue that is both inherited and embellished by driving tractors in the days predating cabs and ear protection. In the heat of the day, the cicadas sound like a much louder version of my head when the tinnitus acts up. Millions of male cicadas are now in the treetops singing for a mate. Females reply with wing clicks and lure in the males.
Nixon says we can look forward to this loud, lurid behavior for the next several weeks. . The female cicadas use ovipositors (egg-laying devices) to slit twigs and insert eggs. Most attacked twigs are about 1/4 inch (pencil-sized) in diameter, but eggs can be laid in branches up to about 2-1/2 inches in diameter. This egg-laying damage weakens the stems, making them susceptible to breaking by high winds.
It’s a teenage wasteland after the fooling around is over. The cicadas die, but leave their legacy behind. Small, rice-like nymphs fall to earth from their elevated twig cribs to the start the cycle all over again. These immature cicadas live by sucking juice from tree roots and growing very slowly. Since they are not very good at flying, Nixon says the highest numbers are found in areas that have been in hardwood trees for years.
I’m enjoying the ruckus. After all, it will be 2024 before we see these cicadas again.