KNOXVILLE, Tenn. (WATE) — Cicadas will soon be popping out of the ground by the millions per acre.

Across the Eastern United States, trillions of the bugs will be popping out for the ground as a part of Brood X. There are more than a dozen such broods, that are on different timelines and this one comes around every 17-years.

Professor of Entomology Frank Hale shared what to expect ahead of the bugs’ appearance in East Tennessee.

“What we need is warm weather and they often say warm weather followed by rain will bring them up. But the soil temperature needs to get around 64, I’ve heard 64 degrees Fahrenheit and I’ve also heard 67. It depends, I suppose maybe on the depth of the soil,” said Hale, “I checked with Dr. (Jerome) Grant, recently he said it was about 60 degrees in Knoxville. So as it warms up these will start coming out more”

Another thing Hale said to watch out for is holes in the ground. They will appear right before the cicadas come out, therefor the more holes you see in the ground, expect more cicadas in that area.

The beady-eyed critters will show up on just about every vertical surface. They’re not likely to do much damage to plants unless you have young trees like in an orchard. Mature trees won’t be damaged and all those bugs turn into a benefit later on.

To protect a tree, Hale says to cover it with some cheesecloth until mid-June. In addition, he says not to use pesticides because they do not work well on cicadas.

When the cicadas die and decompose their nutrients or their elements are taken back into the soil and actually fertilize the forest you could literally have a million of these per acre that’s a lot of fertilizer.”

Frank Hale, entomologist

To our ears, the buzz of cicadas is just one huge din but Hale tells us there are actually three species each with their own call and the cicadas can tell the difference.