COLUMN: Iowa's cicadas

   Have you heard them yet? The constant drone or buzz of annual cicadas.

     These strange looking insects emerge from underground each summer in July and August. Their dried empty exoskeletons provide evidence of their presence as they begin their romantic serenades from the treetops as adult cicadas.

     The cicada’s emergence is easily noted by their loud constant droning song. Male cicada’s songs fill the air from morning till night by using special structures called tymbals, found on their abdomen. Surprisingly loud – a cicada’s buzzing drone seems to come from everywhere. Reaching up to 106 decibels, a cicada’s buzz can be as loud as a lawn mower.

     Annual cicadas are present each year, unlike periodical cicadas, which depending on the brood, emerge on a 13–17-year cycle. Eastern Iowa’s next large periodical cicada hatch will make an appearance in 2024. Annual cicada nymphs spend 2-5 years underground feeding on root juices before emerging as adults to mate and lay eggs – continuing the lifecycle.

     Many of our annual cicadas have dark eyes and greenish colored bodies, unlike the periodical cicadas distinguished by red eyes and blackish colored bodies. (For detailed information and images of area cicadas visit http://www.cicadamania.com/genera/).

     Exoskeletons of emerging cicadas in your neighborhood can often be found clinging to tree trunks. Check out the trees in your yard! Adult cicadas can live for five to six weeks. After mating, females will pump eggs into small slits on twigs. Slits are created with the aid of the sickle like ovipositor on the end of the female’s abdomen. Eggs hatch six to seven weeks later with the newly hatched nymphs falling to the ground and burrowing from 1-2 feet into the soil, where they will feed on the tree’s roots and wait for their turn to emerge as adult cicadas.

     Cicadas do not bite or sting and can be handled safely for a closer look. Live cicadas may struggle to fly free, and males might even make a loud buzzing sound that helps startle potential predators. Cicadas are a valuable insect food source for wildlife such as birds, mammals, frogs, fish, and other insects.

     To find out if cicadas are in your area simply cock your ear toward the trees as you listen for their familiar daytime summer song. You can also check out the trunks of the trees in your yard to see if you can find their telltale remnant nymphal skins. (Fun fact:  Most cicadas sing during the day.)