What is Brood X? When do cicadas come out in 2021? Answering your buggiest questions.
Sometime this spring, billions of cicadas that have been underground since 2004 will emerge en masse and blanket parts of the Eastern United States with their song and, eventually, their carcasses.
If you’re in the right location, they will be impossible to ignore.
A true cicada census is impossible, but scientists expect that some places will have more than a million cicadas per acre, which could equate to more than 25 or 30 per square foot.
When do the cicadas come out in 2021?
That depends on the weather. This brood has been quietly rummaging around underground for the past 17 years and will not emerge until the soil temperature about a foot below ground reaches 64 degrees. Most will wait for a humid (but not stormy) evening to pop out of the tunnels they’ve been building for weeks.
They don’t all appear at once, but it may seem like it. . .
What is Brood X?
These cicadas are not the usual green ones that show up in some parts of the country every year.
Brood X — pronounced “Brood 10,” because cicada broods are labeled with Roman numerals — is one of the largest of 15 broods of periodical cicadas in the United States. (Three broods come out every 13 years and 12 come out every 17 years.) Three species make up Brood X, and they are known for their fire-engine-red eyes, their deafening choruses and their dramatic emergence every 17 years.
https://www.washingtonpost.com/dc-md-va/2021/04/01/cicadas-come-out-2021-brood-x/?
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I live in the eastern part of Tennessee and I well remember their emergence when my son was a little guy in the 1980s. We lived in Nashville at that time. I can definitely believe that it’s possible there could be a million per acre. There were so many of them that we couldn’t walk to our cars without accidentally stepping on them on the sidewalk and driveway.
When we left our windows open in the house in the late afternoon to catch a nice breeze, the cicadas were so loud that it was hard to hear what we were saying!
I think they are fascinating. I remember reading that birds and animals will gorge themselves eating them because they are everywhere....and they apparently aren’t very fast-moving.
Let us know when they appear where you live. I’ll do the same. It may not be too long!
I wanted to share this.
truly, a nightmare scenario 
....and I really avoid stepping on them!
It's been a while since we have had to deal with them. I do remember that they were everywhere, flying through the air, ending up in our car, and crawling on the ground, sidewalks, and driveway....I know they were searching for mates. My husband and I did our best not to destroy any of them. They were just living their lives as they were meant to live them, and they intended no harm. One did fly up my husband's pants leg once, which he only discovered while he and I were sitting in a dental office waiting room! That was interesting.....LOL!
I am not sure what it will be like when they emerge this year. I will be sure to post about our experiences, though!
I'm very grateful they don't bite!
don't know if I could survive that. 
I'll try to watch for your report from the front lines, and drop by to offer my commiserations. 
I have a humane “bug vacuum” that sucks them up safely so I can then take them outside and let them go. I will definitely come back here and share my experience later!
I can hardly wait, elleng!
