After 17 Years Underground, Cicadas Stage a 2020 Southern Invasion

They break through the ground, like the undead emerging from graves.

They scuttle in huge packs in the same direction, through the forest floor and up trees where they settle on the branches. There, they break out of their exoskeletons, at first sickly white and soft before they take on their red-eyed, coal-black adult form and fly off by the billions.

“They’re big, they’re noisy,” said Eric Day, an entomologist at Virginia Tech. “What’s not to love about them?”

Periodical cicadas’ life span is among the longest of any insect, but they spend only a sliver of their days in the sun. After growing underground for 13 to 17 years, a brood will come out in one of 15 specific regions of the United States. This year, males have already started calling out to females in southwest Virginia, West Virginia and parts of North Carolina, the mating grounds of Brood IX.

Typically around this time, Mr. Day starts getting calls for advice from nervous brides and grooms fearful that cicadas will drop in champagne flutes or disrupt outdoor ceremonies with their loud buzzing, he said. (The sound is made only by the male, which has a membrane in its abdomen that vibrates to attract females.)

But with the coronavirus limiting gatherings, this could be a good time for Southerners to sit in their backyards and marvel at the creatures, Mr. Day said. Some may even be tempted to eat them, according to Mr. Day, who in the past has fried them up with sake and garlic.

“This is a biological phenomenon,” he said. “So we can observe them and maybe even enjoy them.”

Debbe Noonkester has no such plans. Ms. Noonkester, who owns Windy Hill Orchards in Ararat, Va., near the North Carolina border, said she was worried about the damage the cicadas could do to her young apple and peach trees.

Cicadas are not poisonous — a big part of their appeal to animals — and they do not harm humans. But they lay enormous quantities of eggs on small twigs, which does little damage to mature trees but can stunt the growth of young trees and vines, or even kill them.

“They’re like those old horror movies,” Ms. Noonkester said.

Ms. Noonkester said she had heard the familiar buzz saw sound of the cicadas on a recent Sunday and had immediately thought of the scene in “The Shining” in which Jack Nicholson bursts through a door with an ax and announces menacingly, “Here’s Johnny!”

She has sprayed the orchard grounds with poison to keep down the number of emerging nymphs, as young cicadas are called, but has been careful to leave the trees alone. Ms. Noonkester said she did not want to kill the spiders and other predators that eat the cicadas.

“We like our meat eaters,” said Ms. Noonkester, who also does her part to hunt the insects. (If she sees a recently hatched cicada on a leaf, she grabs it, throws it to ground and stomps on it with a parting message: “Take that, you fool.”)

Individually, cicadas are helpless. When they shed their exoskeletons, their wings are wet, and they must wait for them to dry before they can fly off, making them vulnerable to predators who grab them and gobble them up. The insects also fall easily into ponds, where frogs and turtles can snatch them.

Their primary defense? Sheer numbers.

Shortly after a brood emerges, predators are quickly overwhelmed by the insects’ abundance.

“Predators can’t make a dent in the population,” said Doug Pfeiffer, a professor of entomology at Virginia Tech.

The billions that are left alive can then mate in peace and lay their eggs. The adults quickly die off after their work is done. Once their eggs hatch, the nymphs fall to the ground, where they will nestle into the earth for the next 17 years.

The predictability of the cycle makes it possible for farmers to plan ahead, he said.

For that reason, Professor Pfeiffer recommends that growers avoid planting new trees in the year or two leading up to an emergence, he said.

Ms. Noonkester said she expected that cicadas would come from other parts of the state and descend soon on her young trees to lay eggs. All she can do, she said, besides hoping that a majority of them will stick to the forest, is prune any twigs that they do damage and keep grabbing and stomping errant cicadas.

“There goes one flying over me now — I couldn’t reach him,” she said. “He’s flying into the woods. He knows better.”

source: nytimes.com