NASHVILLE, Tenn. (WJHL) – East Tennesseans are bracing for the emergence of a brood of cicadas that has been underground since 2004.

According to a spokesperson from the Tennessee Department of Agriculture, the periodical cicadas should emerge during the middle of May, depending on soil temperature.

“A soil temperature of 64 degrees at a depth of 8 inches or 67 degrees at 4 inches will trigger the beginning of the emergence,” according to TDA.

TDA expects the cicadas will remain prevalent until late June.

While the cicadas range covers a wide berth, East Tennessee can anticipate the highest population this summer.

TDA cited reports from 2004 conducted by the University of Tennessee Extension Service that indicate cicada populations in 2021 will be heaviest from Knox County and Blount County heading northeast to Johnson County.

The extension service reported that the brood expected to emerge in 2021, Brood X, has “the largest emergence of individuals for the 17-year cicada in the United States.”

“Middle and West Tennessee should anticipate more scattered and light populations,” TDA reports. “Many Tennessee counties in the Central and Western Regions will probably not see them at all.”

In 2004, the University of Tennessee Extension Service reported Brood X had no significant detections in Middle and West Tennessee counties.

You can read the full 2004 report below:

The insects will likely have an impact on outdoor events in East Tennessee after they emerge.

TDA warns that activities like weddings, concerts and graduations should be moved away from wooded areas into a more open environment further from trees.

Event planners concerned with noise and the presence of the cicadas are advised to move activities indoors to avoid any distractions.

Cicadas can also have an impact on plant life when a brood emerges. As such, TDA advises Tennesseans not to plant young trees until they are gone in late June.

“Otherwise, try to enjoy the special time with the cicadas,” TDA said.

The cicadas can also serve as a fishing opportunity. TDA referenced the Missouri Department of Conservation who reports that the periodical cicadas can create a “brief food bonanza for birds and fish.” Fish will essentially start feeding binges and bite anything that resembles a cicada.