What Are Brood X Cicadas? (2024)

FAQs

What Are Brood X Cicadas? ›

Brood X is a type of periodical cicada. Periodical cicadas are the cicadas that have a long life cycle. So they're every 13, or every 17 years. Brood X happens to be a 17-year cicada, which means the last time it was out of the ground was 2004.

Map of periodic cicada broods with Brood X shown in yellow. Every 17 years, Brood X cicada nymphs tunnel upwards en masse to emerge from the surface of the ground. The insects then shed their exoskeletons on trees and other surfaces, thus becoming adults.

After they've found a tree or shrub to land on, the cicadas will mate and lay eggs at the end of branches. Newly hatched cicadas will then chew through the branch tips, causing them to fall off, carrying the young insects back down to the soil where they will spend the next 17 years.

Benefits of Cicadas

Cicadas are not dangerous and can provide some environmental benefits including: Cicadas are a valuable food source for birds and other predators. Cicadas can aerate lawns and improve water filtration into the ground. Cicadas add nutrients to the soil as they decompose.

Cicadas do not hatch out of the ground (they hatched from eggs in tree branches 17 years ago), and they do not “hibernate” (they are underground actively feeding). When they moult to become adults, the correct term for that process is “ecdysis.”

Crawling out from underground every 13 or 17 years, with a collective song as loud as jet engines, the periodical cicadas are nature's kings of the calendar. These black bugs with bulging eyes differ from their greener-tinged cousins that come out annually.

As trees go through their seasonal cycles, shedding and growing leaves, the composition of their sap changes. And when cicada nymphs feed on that sap, they likely pick up clues about the passage of time. The 17th iteration of the trees' seasonal cycle gives the nymphs their final cue: it's time to emerge.

Cicadas are largely harmless to humans and animals. They don't bite and they don't sting. They lack the physical structures to hurt people that other insects have: they don't have stingers so they can't sting and their mouth parts are a more like a straw than teeth so they can't bite.

They don't sting or bite, and are not poisonous. In fact, the Environmental Protection Agency (EPA) says they can be a great food source for birds and are nutritious for the soil once they decompose. They may be damaging to young trees if female cicadas decide to lay their eggs in one.

Cicadas are not dangerous. They do not sting or bite because they don't have the appropriate mouthparts. They're also not harmful to pets, crops or gardens. Cicadas won't eat leaves, flowers, fruits or vegetables, although they may eat some sap from trees and shrubs, the EPA says.

Are cicadas good or bad for the garden? ›

They're not as bad as they seem

They don't bite, they don't sting, they don't spread disease, and despite their swarming numbers, they don't do much landscape damage. The main plant-injury threat comes from egg-laying. Female cicadas cut small slits in young tree branches, then lay little white eggs in them.

Cicadas damage fruit trees in two ways. The most obvious damage is done during the egg-laying process. The slits made by the female in small branches severely weaken them; often the weakened branches snap off in the wind. Under a heavy attack a majority of the branch tips may be killed.

Periodical cicadas don't bite or sting, and they're harmless to humans, animals and most plants, Lawrance added. But they are noisy.

Periodical cicadas are insects that spend most of their lives underground as nymphs, feeding off the sap of tree roots. They emerge to transform into adults and mate. Some periodical cicadas emerge every 13 years and others emerge every 17 years. The males "sing" by vibrating a membrane on the sides of their bodies.

Despite their name, annual cicadas generally live for two to five years—though some species may live longer—and their brood life cycles overlap, meaning that every summer, some cicadas emerge.

Next, male cicadas fill the air with shrill buzzing sounds created by rapidly vibrating drum-like plates on their abdomens. The females make clicking sounds with their wings if they like the song. They mate, lay their eggs, and then both male and female cicadas die after just about five weeks aboveground.

After mating, the female makes slits in tree branches and lays eggs there. The eggs hatch six to seven weeks later, the nymphs fall to the ground and go into the soil, and the cycle begins again. The adult periodical cicadas only live three to four weeks.

The cicada nymphs hatch from their eggs in trees. After a few days, they fall to the earth and burrow underground, where they spend their time tunneling through dirt and eating the sap from tree roots. They live that way for 17 years in their nymph form.

The cicada killer wasp gets its name from, as you would guess, killing cicadas. The female cicada killer wasp has a stinger that she uses to inject venom into cicadas, not killing the cicadas but instead paralyzing them. She then flies the cicada to her nesting area, dragging it underground.