bring ‘em on: the magic of periodical cicadas

Periodical cicadas, photo copyright  U.S. Forest Service/ Bob Rabaglia

I CAN’T WAIT FOR THEM to announce themselves noisily, though readers have been writing in, expressing varying degrees of cicada anxiety. Brood II of the periodical 17-year cicadas—the brood that returns on that uncanny schedule specifically to parts of the East, from Georgia to Connecticut, are already being sighted where soil temperatures have warmed to the preferred 64 degrees. As with all things, I’m most fascinated by these insects’ role in the bigger ecological picture—besides the sheer magical aspect of witnessing their incredible orgy. Some cicada facts I’ve learned:

intriguing periodical cicada facts

  • There are other cicadas that appear annually–sometimes called dog-day cicadas—found around the world, but the periodic types, appearing every 13 or 17 years, only occur in North America. (The periodicals are genus Magicicada; the dog-day types are genus Tibicen.)
  • Though sometimes referred to as the 17- or 13-year locusts, periodical cicadas are not locusts (which are a kind of grasshopper).
  • The periodical types were first noted in scientific literature in 1665, under the heading, “Some Observations of Strange Insects, and the Mischiefs done by them.”
  • Today, each cyclical population of periodic cicadas is called a brood, and there are a total of 15 broods.  A chart of all the broods and locations is here. (Other broods in other regions than the East’s Brood II are on a different timetable.)
  • Cicadas don’t bite or sting. (And if you have a dog, don’t worry if he/she chases them and eats them.)
  • On the ecological scale, they seem to do more good than harm. Though some “flagging,” or browning and dieback may occur on young twigs that the females prefer to deposit their eggs into, and some root and other tissue feeding on plants may occur, the cicadas also leave behind much goodness:
  • “The mass emergence can benefit the longer, overall health of eastern forests,” says U.S. Forest Service Michael Boehne on the UDSA website. “After mating and laying eggs, adult cicadas die and fall to the forest floor. The nutrients released from the mass decay of the brood create a jolt of healthy nutrients available to forest organisms. Researchers have shown that this pulse of nutrition leads to an increase of beneficial microbes and nitrogen in soil, increased tree growth and more robust wildflowers.”
  • Young trees—ones four years or younger, such as in a young orchard, most references say, meaning whose wood is within the preferred range for egg-laying–could be covered in defense if you are in an area where population densities are high.
  • Periodical cicadas are a foodstuff for various birds (including catbirds and bluejays, to name two familiar species). One recent research theory says they may outsmart predator birds with their uncanny timing—that perhaps their 13- or 17-year timing coincides with population dips in bird species that favor them as food, or even influences the dips. Wild! Read about that theory in “Scientific American.”
  • You can help track the emergence of Brood II (which occurs when soil temperatures reach 64 degrees F) as part of a citizen-science project being undertaken by the public-radio program Radiolab.  Me, I’m hoping to have the privilege of seeing them—though there’s no guarantee in any given spot that you will, even in an emergence year.

articles i enjoyed on periodical cicadas

  1. Linda B Secrist says:

    i think you should run a contest for the best way to cook and eat the little darlings. Could be very creative

  2. skubitwo says:

    i remember a summer when my next younger sister and i collected hundreds of the cast off exoskeletons. such perfect little fragile copies of the larvae, incredibly detailed, clinging to all the trees with their little claws after the adult sheds the skin. being older sisters, we decorated our t-shirts with them by hooking the little claws onto the fabric and carefully walked into the house and scared the be-jeebers out of baby sis.
    yes, mom ‘tanned our little fannies’.

    1. margaret says:

      Hi, Zina. First, ask your local Cooperative Extension if there is an emergence nearby and what the outlook is for your area. As for coverings: Kind of depends how tall they are and whether they are leafed out and so on. A very lightweight cloth such as Agribon 15 (very light Reemay) might work, but you have to think about wind and possible damage to leaves if there is wind, and the fabric flaps around. If they are not too tall, I would prefer to create a “tent” or “cage” covered in the fabric rather than lay anything on the tree directly. I have sometimes created tents for big plants with tomato cages, lawn chairs, bamboo poles, ladders — you name it — then clothes-pinned or clamped fabric to the armature. Whatever works to create a structure.

  3. Hi Margaret,
    I confess for a fondness for cicadas myself. Thought you might like my poem about experiencing them in Louisville, KY–It’s a Blessing from my Blessings and Curses series:


    In the middle of last May,
    after three successive rains softened the soil,
    magicicada septendecim began to emerge
    in great numbers from the earth.
    For seventeen years it had lived underground,
    feeding on the fluids of tree roots,
    growing from ant-sized to wasp-sized.

    The exodus began at sunset:
    in perfect synchroneity the nymphs
    appeared from tunnels underground
    climbing whatever they could find,
    trees or shrubs or telephone poles,
    discarding dried-out carcasses
    in the final molt to adulthood.

    Soft and white at first,
    as their exoskeleton hardened,
    they turned dark and brittle
    with lacy, orange-veined transparent wings,
    orange legs, and beady red eyes.

    In choruses in the sunlit treetops,
    the males courted the females
    with music made by ridged tymbals
    vibrating against their abdomens,
    the reverberating sounds arousing to both sexes.

    The males played one song to locate females
    and another to approach them with;
    the females signaled their receptivity
    in rhythmic wing flicks
    increasing in speed and intensity,
    while the males vied with each other,
    each hoping to sing a duet
    with a flickering female.

    In the ecstasy of union her wings grew still
    as he burst into the culminating solo.
    In the Ohio River Valley,
    at the height of the year,
    they were as numerous
    as drops of rain.
    Large, clumsy fliers,
    they frequently collided
    with creatures and objects
    moving or still.
    Their shrill songs saturated
    the atmosphere,
    drowning the noises
    of lawnmowers, traffic,
    the roar of planes.

    There was no harm to them,
    no sting, or bite, or menace.
    Their life was to sing, fly, mate, eat,
    and bask in the light of day
    and dark of night.
    Birds and animals feasted on them.
    They perished in droves,
    their brittle corpses piled up
    like leaves in autumn.

    They were no plague but a blessing
    to remind us of the vastness,
    greatness, and mystery of creation.

    They damaged only the tips of trees
    where females lay their eggs,
    which recovered after two months
    when the eggs hatched
    and the nymphs dropped to the ground
    and dug tunnels in the earth
    to aerate the soil and drain it,
    there to develop in the darkness
    of the next seventeen years.

  4. Eric says:

    A bit off topic – I was in the Concord, MA audience last evening. Your presentation was wonderful, so glad I decided to attend. I wanted to stop and say Hi and thank you for some good advice you gave me here some years ago concerning a common favorite, a Japanese umbrella pine. Ours is flourishing and it was nice to hear more about yours as well. You were busy though so I didn’t want to bother you. Thanks for an enjoyable evening!

  5. emily says:

    Cicadas are also an awesome cat toy. When the cat reaches out and touches one, it buzzes loudly and moves a bit. My cats are always fascinated by this. (Please don’t criticize me for allowing my cats to annoy the cicadas.)

  6. Dahlink says:

    We first experienced one of these amazing cicada events many years ago in Maryland. What most deeply impressed us was that our neighbors didn’t need to feed their dog for about a month! Our older son made a mental note to be “somewhere else in 17 years” and he was able to make good on that promise to himself.

  7. Pat says:

    So funny , my dogs loved chewing on the critters, would bring them into the house for snacks. The noise was deafing!

  8. Jane says:

    My daughter calls their “song” the sound of summer that brings back memories of her summers at her grandmother’s house.

    1. margaret says:

      Yes, Anne — there are 15 broods around the nation, and the Eastern one (Brood II) is on its own schedule as is each of the others. Those links in the story to the brood chart/map explain.

  9. Kassie says:

    Thank you for this post! These periodic cicadas are such a wonder, they literally blow my mind at the amazing devices of Mother Nature. Their emergence years offer a unique opportunity for nostalgia; I remember quizzing my niece in her childhood, “How old will you be when they come again?” And then, rejoicing when that year came around again. Just magic.

  10. Amy says:

    Ha, happy to see fellow cicada lovers! I thought I was alone! :) I’m irrationally excited by this emergence. I work on a heavily wooded university campus in Baltimore so am really hoping to get a glimpse.

  11. Sandra says:

    I’m still on the fence about cicadas. I really want to like them, really I do. I just need to get past my initial creepy, crawlie reaction. I will come back to this post to help soften my stance. Thanks so much!
    Blissful tidings,

    1. margaret says:

      Hi, Sandra. I used to be much more reactive to the creepy crawly issue but over the years in the garden I have learned to let fascination and curiosity take hold, not fear or revulsion. :)

  12. Spy Garden says:

    We had the 13 year cicadas in Missouri in 2011. It was unbelievable. They were so loud you almost had to shout when outdoors: in the middle of the day! We had fun dodging them! There were thousands and thousands of their discarded outer shells piled all over our yard. It really was an amazing sight!

  13. Fred says:

    Seems the only way to date this article is by looking at the comments. The opening paragraph is time sensitive to 2013. So here I sit anticipating Brood X in 2021.

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