I am new to Tulsa and am amazed by how loud those insect sounds are that are coming from the trees? I assume they are insects. Right? SP

You are correct, they are insects and each year we know we are in the thick of summer with the arrival of those loud nighttime insect sounds. That insect is a cicada and cicadas have a very interesting life.

Oklahoma plays host to at least 12 species of cicadas. These cicadas are grouped into what are called broods with different broods becoming active at different times. For example, Brood IV are in a 17 year cycle meaning that it spends 17 years underground before emerging. Brook IV was active in Oklahoma back in 1947, 1964, 1081, 1998, and 2015, which means they won’t be emerging until 2032.

The most common cicada in Oklahoma is the Dog-Day Cicada. Dog Day Cicadas have a life cycle of between 2 and 5 years. The sounds we hear coming from the trees at night is actually the male cicada trying their best to attract a female. The males beat their wings rapidly against their abdomens to produce this sound utilizing a specialized organ on each side of their body called tympana which helps to amplify the sound. If this sounds loud to you, you are correct. These cicada mating calls have been recorded as loud as 108 decibels which is about the same as a car horn measured from about 3 feet away. That’s loud.

After mating, the female cicada lays her eggs into twigs and small branches by using a saw-like egg laying body part called an ovipositor. Six to seven weeks later, small nymphs hatch and fall to the ground. At that point they burrow down into the soil, up to several feet deep where they live out the majority of their lives. During this time they go through several developmental changes called “instars” before emerging.

After emerging, they climb up onto a tree, fence, or any appropriate structure really where the adult cicada emerges from its final growth stage leaving behind the crunchy shells most of us are familiar with. The adults can live 5 to 6 weeks and the process to create the next generation begins again.

Even though the nymphs and adults do suck sap from trees, there’s really no cause for concern. Plus, they are no danger to our flowers or vegetables. So, welcome to Oklahoma. We hope you enjoy the nightly cicada concerts! Good luck!

You can get answers to all your gardening questions by calling the Tulsa Master Gardeners Help Line at 918-746-3701, dropping by our Diagnostic Center at 4116 E. 15th Street, or by emailing us at mg@tulsamastergardeners.org. Photo: Joseph OBrien, USDA Forest Service, Bugwood.org