Invasion of the Cicadas

This summer, billions of Brood cicadas will emerge from the ground. Some have lived in the soil for over a decade, and some for almost two decades. There are over 190 varieties of cicadas in North American and over 3,000 worldwide.

Thankfully the large numbers of cicadas aren’t coming to the Gulf Coast. The only thing we get here is the annual or “dog-day cicadas,” called that because of their emergence every year during the dog days of summer, although all cicadas, whether Brood or Dog-day, emerge in the summer.

Brood or “periodic” cicadas appear after a set amount of years.  There are 12 brood emergence periods for the 17-year cicadas and three for the 13-year ones. Check the map for more information about their emergence dates.

The most considerable bulk of the Brood cicadas are east of the Mississippi. Some didn’t read the instructions, so many of them have invaded some areas west of the Mississippi River. There are 23 Brood “hatchings” ranging from New York to North Texas and Louisiana to the Great Lakes.

Only a few areas in Texas

However, only a few counties in northeast Texas, Louisiana, Mississippi, and Alabama have some 13-year Brood emergences.

The Texas brood (number IV) will burst out of the ground in 2032, which is a long way off. They are only present in a few counties in northeast Texas. They crossed the Red River without authorization from the Texas legislature and have ensconced themselves from Clay County to the Louisiana border.

In Louisiana, Brood XXII (22) has settled north and west of Lake Ponchartrain, roughly in part of the Florida Parishes:  East Baton Rouge, East and West Feliciana, Pointe Coupee, and Livingstone.

Mississippi infestations are a little more north, with Brood XXII extending east from Wilkinson County and Pike County and Brood XXIII going roughly from Walthall, Marion, and Lamar counties northward to Illinois.

As you can see on the map below, each Brood has a different year of appearance. Brood XXII will appear in 2027, and XXIII will appear in 2028.

Now for the Dog-Day Cicadas

Dog-Day or annual cicadas emerge each year, from April through July. And some even into August. All of the cicadas we see on the Gulf Coast are dog-day cicadas. Their life cycle is the same as their Brood cousins, only shorter.

Cicadas won’t damage crops, per se. Adult females may cut a hole in a leaf or a small slit in a stem to lay their eggs on, but no harm will come to the plant. It may flag a little, but it will recover. Please don’t use pesticides on them. They provide food for many terrestrial and aquatic animals. Using poisons to kill the cicadas will harm animals that eat them and kill other beneficial insects.

Cicada Lifecyle

A female cicada, once she breeds, will lay eggs on a stem or leaf.  Once the eggs hatch, the larvae, which resembles a small termite, will feed on plant sap. When it’s ready, it will drop to the ground and begin to dig. Typically, it will start with grass roots and then graduate up to the roots of its host plant (usually a tree.

These nymphs will spend all their time tunneling and feeding. One of the real benefits of cicada nymphs is that the tunneling aerates the soil and helps create a healthier biome.

Once its time underground is over (whether it’s a year or 17 years), it will emerge from the ground. It then climbs the nearest vertical surface and begins to shed its exoskeleton. I remember sitting on my patio one August night, watching an adult cicada arising from its nymph shell. It took several hours to complete shedding the shell and then pump up its wings fluid. It was a fantastic sight to watch.

Adults spend their time in trees looking for a mate. The noise you hear is males singing and the females responding. The cycle begins again.

1 thought on “Invasion of the Cicadas

  1. what makes some stay underground for so long yet others only a year? After reading this post I think theyre pretty cool now!

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