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The Arrival

“The greatest danger facing our world has been the planet’s best kept secret … until now.”

I’m a sucker for cheesy sci-fi films.  This is the tagline for the 1996 movie, The Arrival, starring Charlie Sheen back before he was #winning.  In the movie, aliens have been living in disguise on earth for a number of years, and they have an underground base that they are using to terraform the planet.  The aliens are trying to raise the Earth's temperature to not only kill off humans but make the planet hospitable for themselves.  Are you ready for the arrival?  Soon we will have an alien invasion of our own.  This is the year of the 17 year cicadas.  Umm … run for your lives?

Brood V is the group that is ready to make their presence known in West Virginia, Ohio, and parts of Virginia, Maryland, and Pennsylvania.  Periodic cicadas are found only in eastern North America, and have 13- or 17-year life cycles. Brood V has a 17-year life cycle, which means that the adults emerging from the ground this summer have been feeding on tree roots roughly since 1999.

In May, when soil temperatures begin to exceed 64 degrees Fahrenheit, the nymphs will emerge from the ground to climb onto a tree or similar surface, shed their exoskeleton and become winged adults. From that point, the cicadas will only live a few weeks to reproduce, then will die.

There are literally billions of 17 year cicadas. Why? One theory suggests that the large number of cicadas overwhelms predators, so predators are never able to eat them all and cicadas, and many always survive to mate. This is a survival strategy called “predator satiation”.

The biggest concern about 17 year cicadas is their potential to damage young trees. The truth is they will damage limbs on the weakest of trees in your yard.  You should consider placing netting around young trees if the cicadas visit your yard. Also you can try hosing them off with water, placing insect barrier tape around the trunk of the trees, or picking them off like grapes! Cicadas actually benefit the health of trees by aerating the soil around the roots, and trimming weak or damaged limbs.

It is important to mention that cicadas do not cause damage to plants by chewing leaves like other insects do, such as caterpillars. These are not the locusts associated with destroying the entire food supply of nations, nor are they the locusts mentioned in the Bible.  Damage from cicadas occurs during ovipositing, or in some extreme cases, when they feed on the roots of trees.  The weakest limbs of a tree are often temporarily damaged or killed off, the result of which is called flagging, as the leaves of the branch will turn brown and look like a hanging flag.

In many cases, they are doing the trees a favor by pruning their weakest branches.  The silver lining in all of this is that periodic cicadas are very beneficial for the environment, they aerate the soil, their bodies contribute nitrogen and other nutrients to the soil when they die and they serve as a food source for birds, mammals and fish.