The Cicadas are now Invading! Are they Harmful?
Any day now, if it hasn’t happened already, the Brood X cicada will
emerge from its 17-year nap underground and wreak havoc in your neighborhood.
The main question on a lot of people’s minds is, “Can these giant bugs do
anything bad to me?”
That depends on your definition of “bad.” Will the bugs attack you? No.
They don’t bite. But they will be disruptive, especially if you live near an
area whose soil has been undisturbed. In places like this, 200 nymphs, which are
burrowing their way to the surface as we speak, can emerge from one square yard.
An acre of undisturbed soil can yield 1½ million of the critters.
The nymph cicadas have been feeding on the sap in tree roots since 1987. When
they reach the top of the soil, they climb trees or other surfaces that look
similar to trees to them—such as poles—and shed their skins. They then fly
into the trees, and the males make loud buzzing sounds as they try to attract
How loud is that buzz? In some areas, it can be measured at 80
decibels. That’s louder than many residential limits of 65 decibels. And it
can definitely be loud enough to drown out the sound at outdoor weddings and
After the females mate, they cut slits in the bark of twigs and deposit eggs
in the slits. Females generally lay about 400 eggs each. The eggs hatch in six
to 10 weeks. The hatchlings, or nymphs, which look a bit like ants, drop to the
ground and burrow under the soil. We’ll see them again in 2021—17 years from
The bottom line is that this year’s cicadas are not really harmful. They
don’t do much damage to trees—it’s more like a natural pruning, although
very young trees are at some risk. Cicadas don’t bite people. They can sicken
pets who decide to eats hundreds of them in one day, but the illness isn’t
fatal. There was one story 17 years ago about train tracks that got so full of
dead cicada bodies that a train wasn’t able to stop as quickly as usual, but
that story is unverifiable today.
So relax and enjoy this phenomenon. It’ll only last four to six weeks. You
may want to re-think any plans for outdoor parties though, unless you love the
crunch of cicada in your potato salad.