Cicadas, You, and Your Trees

An infestation of periodical cicadas After a 13-year nap underground, Brood 19 cicadas are waking up in immense numbers this year. Image: Pennsylvania Department of Conservation and Natural Resources/Forestry Archive/

Squeamish about bugs? Better start packing, because you’ll want to be out of town between now and July if you live in a swath of Southern states where Brood 19 is emerging to get busy with each other.

Brood 19 refers a particular group of periodical cicadas, which emerge in fantastical numbers from a 13-year nap underground. Biologist Gene Kritsky told NPR he’s expecting billions of cicadas this year.

The mating cries of the big, red-eyed male cicadas looking for love will fill the air in parts of Alabama, Arkansas, Georgia, Illinois, Indiana, Kentucky, Louisiana, Mississippi, Missouri, North Carolina, Oklahoma, South Carolina, and Tennessee as the 13-year cicadas climb out of the ground. The brood in your neighborhood might come out in a different year.

Cicadas don’t bite or sting. They mostly make a lot of noise—up to 85 decibels—and shed their not-so-little brown skins under your oak and maple trees the way teenagers pile clothes on the floor. And when they die, they create quite a stink simply because of their large numbers.

The noise, stink, and mess are annoying. But more annoying is the damage they can inflict on young trees, shrubs, and bushes:

  • Fruit trees
  • Grape vines
  • Blueberries
  • Dogwoods
  • Azaleas
  • Rose of Sharon
  • Roses
  • Raspberries
  • Grapes
  • Black-eyed Susan
  • Hollies
  • Spirea
  • Rhododendron
  • Viburnum
  • Junipers
  • Arborvitae

The female cicada rips into their branches to lay her eggs. The rips she makes can weaken limbs and provide entry points to disease and other harmful insects.

What to do—and not to do—to protect your trees and plants from cicadas:

  • Don’t attack them with pesticides. The cicadas you kill today will be replaced by a billion more cicadas tomorrow.
  • If you’re worried about a particular young plant or tree, create a net-like barrier between the plant and the cicadas. Cheese cloth works well. But make sure to fasten the cloth around the trunk so the bugs can’t crawl up underneath it to get to the limbs.
  • If you don’t have time to net, a little post-cicada pruning will get your plants looking good again.

And the rotting cicada carcasses? Toss them into your compost pile (run them over with your lawn mower to help break down the carcasses). Or suffer through the smell (it lasts a couple weeks) knowing that as they decay, they’ll add nutrients to your plants.

We think dead cicadas smell a bit like strong cheese. What do they smell like to you? Are you anticipating or dreading the arrival of these loud-mouthed insects?