Thursday, June 1, 2017

Cicadas Emerging

When I think of the sounds of summer, the metallic songs of cicadas immediately comes to mind.  Cicadas are starting to emerge and make their way from the soil to the trees to serenade us again.  Last night I heard my first cicada calls, but soon the trees will nearly be deafening at times while they call to each other.

Cicadas spend the majority of their life under the soil.  I'm sure you've heard of the 17 year cicadas, which only emerge every 17 years.  But the most common cicadas are the "Dog Day Cicadas."  Cicadas that become abundant during the dog days of summer and take only 2-5 year to complete their lifecycle (still a amazing long time for an insect!)

During summer, cicadas mate and by the end of summer, lay their eggs on twigs and bark.  The eggs hatch into nymphs about a month later and crawl down to the soil and feed on roots.  Usually they do very little damage as nymphs, but adults can be a nuisance leaving markings when they lay eggs on young trees.  The nymphs spend 2-5 years in the soil before they emerge from the soil, crawl up a tree or other object (like the side of your house), shed their nymphal skin and emerge as an adult.  The nymphal skin is left behind, clinging to the spot they last stood.

The new exoskeleton grows underneath the old exoskeleton, so when they crack the old skin open, the new skin can be seen underneath.  The newly emerged adult cicada will rest for a short period of time, pumping its blood through the wings and allowing the exoskeleton to harden before it flies up into the trees to sing.

Most of us can recognize an adult cicada, but when you get a chance encounter with the nymph emerging from the soil, it really is a sight!

Immature cicada emerging from the soil.
Photo Credit: Manu & Indra Gregory