Sunday, August 21, 2011


 The annual cicadas are out and announcing their presence with their high pitched buzzing call.  They are usually high up in the trees but they live short lives as adults and soon drop onto driveways or decks and become food for other creatures.  This one was alive but lying on my driveway this morning.

Some cicada species live underground for many years.  13 years is one, along with the well known 17 year cicada.  But our common cicada is only underground one year.

Cicadas are in the group of insects called Hemiptera, or True Bugs.  This group of insects all have straw-like sucking mouth parts and most use their "straw" to pierce plant tissue and suck out nourishment from the plant.  After mating, female cicadas lay eggs in the stems of tree branches.  The hatchlings drop to the ground and burrow down to one of the tree's roots.  They attach their straw like mouth to the root and stay attached for the next year, growing as the tree feeds them. 

After their year in the ground the larvae crawl out on a late summer night and climb a few feet up the trunk of the tree.  In the picture below you can see the shell left after they emerge from the ground with the dirt still attached.

 Most everybody has found these left over "skins" of a larvae cicada attached near the bottom of a tree with the obvious split in the back where the adult emerged and crawled up the tree to let its wings dry and expand. I found this empty shell on the tree near my driveway where I found the adult cicada. The adult then flies into the branches and seeks a mate.
This is the male cicada that I found.  You can see the slender tube like sucking mouth part sticking down beneath its front legs.

Cicadas are very heavy bodied insects and not very good fliers.

The females listen for the "singing" males, and pick one out that sounds perfect to her.  She then flies to the tree and locates the male by his buzzing call.  After introductions, if all goes well, they mate and the female then finds an appropriate branch to lay her eggs in. 
The male makes his buzzing call by slapping or clapping two pair of plate like body peices together.  Here you can see one pair just below the hind leg and to the left of the green wing edge.  One lays ontop of the other.  As he snaps the top plate down onto the other it makes a snapping sound.  When he does this very fast with both pair of double "plates" the loud high pitched buzzing sound is the result.

Hearing the cicadas always means the peak of summer is past, and I'd better enjoy what is left.

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