But before they died, female cicadas deposited eggs in tree branches. Each female cicada can produce up to 500 eggs. Given the density and coverage of the Brood X cicadas, the number of eggs produced is in the billions.
Now, some of the cicada eggs are showing red eyes, which means the nymphs inside the eggs will hatch soon, according to Paula Shrewsbury, an entomology professor at the University of Maryland. She recently dissected egg nests in her yard in Columbia, Md.
“The eggs are white in color and shaped like a grain of rice, however they are much smaller than a grain of rice,” she wrote in an email, while noting the emergence of red eyes.
Evidence of cicada nests are apparent from the numerous brown patches of leaves visible in the tree canopy across the D.C. area; it’s where female cicadas cut slits in branches to lay eggs. Unfortunately, the cuts often kill the ends of tree branches, which is called “flagging.” It’s harmless to mature trees, but saplings can suffer.
Some trees are more resistant to flagging than others. Oak trees, for example, show flagging, with numerous brown patches marking each cicada nest. Cherry trees, however, are much more tolerant to cicada nests and often survive the ordeal without the branch tips dying.
During the next week or two, eggs will be hatching in the nests. If you were worried about cicada pee spraying down from the trees last month, how about cicada nymphs raining down from above this month?
“Yes, they will rain down and likely fall onto humans,” wrote Michael J. Raupp, an entomology professor at the University of Maryland, in an email. “[A]s much as I like the notion of cicada nymph rain, I doubt that people will notice them. These hatchlings are only a mm [millimeter] or so in length.”
Nevertheless, wearing a hat in the woods is a good idea for the next month. Just in case you walk under the tiny, divebombing nymphs, which resemble small termites.
“They are small and delicate, about the size of an aphid or small ant,” wrote Dan Gruner, also an entomology professor at the University of Maryland. “[They] will be hard to see unless you are looking for them.”
The nymphs typically hatch six weeks after their eggs are laid, Gruner noted, the exact timing depending on “time, temperature, and moisture.”
But what happens to the cicada nymphs after they hatch?
“Once the egg hatches, the 1st instar nymph (immature) will drop to the ground from its tree branch and burrow into the soil where it will search for plant roots to feed on,” Shrewsbury wrote. “The cicadas will go through 5 instars (immature stages) over the next 17 years when they will emerge from the ground in 2038.”
By late August, billions of cicada nymphs will have tunneled underground and started their incredible 17-year life cycle again.
Let us know if you have seen flagging in the trees where you live or have spotted any cicada eggs or newly hatched nymphs.