The Sound of Summer

By Eileen Berger

One of the many benefits of becoming a Master Naturalist is an increased awareness of natural elements.  Though I had always been interested in nature, my life was too full of family and work obligations to just sit and listen.  These last few months have been richer because I have paid more attention to animals and plants not only in parks and nature preserves, but also at home in my backyard.  Having lived all my life in Texas should have meant that I would more familiar with its flora and fauna, but just being exposed to them does not mean that you are attending to them.  Teachers would be the first to understand that difference.

One afternoon this summer I was enjoying my tree-shaded yard, and stopped to listen to the birds, and another sound.  It seemed to echo, or be repeated, in trees up and down my street.  That was when I realized what that sound represented.  It is the sound of cicadas.  I consulted my insect guide, A Field Guide to Common Texas Insects by Bastiaan M. Drees and John A Jackman.  Although cicadas, order Homoptera, have 40 species in Texas, the common Dog-Day cicada, Tibican spp. is perhaps the one I was hearing.  Just the name sounds like summer, with cicadas being active in the months April to July.

The periodical cicada, Magicicada septendecim(Linnaeus) completes its life cycle in 17 years, and emerges in large broods over broad geographical areas, reminding me of the Biblical plagues of locusts.   The Texas periodical cicadas ( also called locusts) have a 13 year cycle,  and some of them emerge every year.

You may not ever notice a live cicada, as they spend a lot of their time in trees. Although the adults vary in size, they all have bulging eyes and semi-transparent wings.  They can be up to 1 and 5/8 inches long. The common dog- day cicada appears in late summer and has a life cycle of 2 to 5 years.  The female lays eggs in twigs and small branches using a saw-like egg laying structure called an ovipositor.  In 6 To 7 weeks, small nymphs hatch from the eggs and drop to the ground where they burrow into the soil in search of tree roots.  As  they molt and become increasingly larger, they continue to burrow deeper into the ground.  Each molting event  is called an instar.  You may have seen the shed exoskeleton of a cicada perhaps on a tree limb.  You may also have seen the ½ inch wide hole in the soil where a nymph has burrowed out of the ground.  It will climb on to a tree  trunk , low- growing plant, or other structure to finally emerge as an adult, which can live for 5 to 6 weeks.  Adult cicadas do not feed on tree leaves.  They may, however, suck juices from tender twigs.  The nymphs feed on tree root sap.

The sound of summer heard throughout Ellis County is produced by the male cicada, resting in a tree, singing to attract a mate.  He produces the off and on buzz by vibrating two membranes in the sides of the insect’s abdomen.  Females lack the distinctive mating sound.

When you walk outside this summer, stop and enjoy the music of nature, thanks to the cidada orchestra.

Comments are closed.