Cicadas – the real story for Virginia

Top: Annual cicada. Credit Bugwood.
Bottom: Periodical Cicada. Credit Eric Day

Cicadas

Despite hype, cicada double-brood emergence won’t affect Virginia, Virginia Tech expert says

https://news.vt.edu/articles/2024/03/ext-cicada-double-brood-emergence-wont-affect-virginia.html

There are annual (“dog-day”) cicadas that emerge every year. Annual cicadas have black-green coloring, while periodical cicadas have black-red-orange coloring.

Annual cicadas, although noisy and large, are not at all dangerous to people. In fact, they are edible, but I do recommend removing the wings and legs first, otherwise it’s too much like eating crunchy food wrappers. Well, I suppose it is eating crunchy food wrappers! The flavor is mild, and the texture creamy.

Annual cicadas can damage young trees, because the females make slits in the bark of pencil-thickness twigs to lay their eggs. The overall effect is like pruning back the twigs about a foot. Not a problem on a big tree, but to be avoided on young trees if possible.

How do you protect young trees from cicadas? Cicadas emerge from the ground in a pupal shell, which they climb out of when they’re ready, splitting the top of the skin. You may have seen these cast shells still gripping on to siding or boards or other things that could be mistaken for a tree. Before too many emerge, cover your vulnerable new saplings with netting, or fabric. If you are a gardener, you may have rowcover or insect netting that will be perfect. If not, you may have old bedsheets or nylon net curtains. Keep the plants covered until no more cicadas are emerging. Cicadas die after laying eggs (I wonder when the males die?)

If you get the chance, stop and watch as an adult cicada emerges from its nymph shell. At first the wings will be crumpled and bright pink. Gradually they will stretch out and dry. Here’s a great little time lapse video of the process. In real life, it takes a bit longer! Note that it is the adult emerging from the nymph, not the nymph emerging.

The hype this year has been about the periodical cicadas. In particular, doomsayers have been trying to panic us into thinking we are all going to be battling a combination of the 13-year cicada and the 17-year cicada in some places. Mostly it’s not true.

Doug Pfeiffer, professor and Extension specialist in the Department of Entomology of Virginia Tech. explains “They have evolved this strategy of emerging all at once in order to overwhelm predators, a defense strategy called predator satiation.

“Periodical cicadas emerge after either 13 or 17 years, both prime numbers,” said Pfeiffer. “That is an adaptation to avoid predators who might develop a converging lifecycle and emerge to eat them.”

Each type of cicada exists as several Broods. Blacksburg, home of Virginia Tech, is on the very edge of the range of Brood XIX (19), a population of 13-year periodical cicadas produced from eggs laid in 2011, resting underground since then. Virginians living south of Caroline County and east of the Interstate 95 are probably seeing and hearing Brood XIX by now. Virginians living along the North Carolina border, especially those in Brunswick County, should also be on the lookout. See the map from Virginia Tech.

Virginia map showing likelihood of finding periodical cicadas in each county. Credit Virginia Tech Extension Service

People in the red zone will get no periodical cicadas. People in the bright green zones will probably get them. Other Virginians are in the maybe zones.

And the scary double-brood? A brood of 17-year cicadas (Brood XII) will also emerge in2024 – in Illinois! Very little geographical overlap!

When it is all over, the dead cicadas lie on the soil, feeding it as they decompose. The eggs hatch into tiny wingless nymphs, which walk down the tree and bury themselves in the ground, sheltering until it’s time to go above ground again, eating nutrients from plant roots.

Here’s a chart of when you can expect periodical cicadas in your neck of the Virginia woods:

Chart of cicada broods in Virginia

We are home to the 17 year brood II, last heard here in 2013. due back in 2030.

And here’s a map

East Coast cicada dates

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