They-re back! This spring, there will be another emergence of the Cicada. What makes this emergence unique and, in some respects, historic, is that this emergence will have two different broods emerging at the same time. The last time this occurred in the United States was in 1803 (Thomas Jefferson was President). This spring, the 17-year Brood XIII and the 13-year Brood XIX will emerge from the ground and begin their transformation from nymph to adult Cicadas. So–as a Master Gardener and for the many gardeners reading this article, the biggest questions are likely to be–will these cicadas eat my garden away? Will they damage my garden?

It might be helpful to understand a little about the cicadas and what they are not. It’s common to conjure up images of clouds of locusts destroying millions of acres of cropland – especially when you hear of an emergence that will include billions and billions of insects. Cicadas are not locusts. It is true that locusts have destroyed croplands because of their voracious appetites but locusts and cicadas are not related…not by a long shot. Cicadas are insects classified in the order Hemiptera – the same as aphids, shield bugs, and leafhoppers. Locusts, on the other hand, are in the family Acrididae–a type of grasshopper. Another key difference that might ease some minds, only Cicadas are found within the United States. There are no native locusts in the United States. The last locust to be recorded in the United States was the Rocky Mount locust (Melanoplus spretus) which was declared extinct in 1902.

Enough about the locusts–hopefully, we dispelled any concerns that the locust and cicada were one and the same. This spring, two broods of Cicadas will emerge at the same time (a brood is a group of cicadas that emerge at the same time). This dual emergence (the 17-year Brood XIII and the 13-year Brood XIX) will find billions of Cicadas emerging from the ground and transforming into adult Cicadas.

Will Cicadas damage your garden? Well, not to the level of locusts, but yes, the Cicada can cause some minimal damage in your garden.

Let’s first understand which brood and where in Western North Carolina, and especially Transylvania County, you are likely to experience the Cicadas. It’s important to acknowledge that past emergence locations do not indicate future emergence sites. Underground Cicada sites are frequently impacted by anthropogenic activities (e.g., urbanization, habitat loss and degradation). It is very unlikely Transylvania County will experience an overlap of the two Cicada Broods. Brood XIII (17-year brood) will not emerge here in Transylvania County and will primarily be seen in IA, IL, IN, MI, and WI. However, brood XIX (13-year brood) will likely emerge in about 16 eastern states–including North Carolina.

As Cicadas emerge, the mating process begins followed soon by the laying of eggs. Female cicadas use their ovipositors to create small incisions in the branches of trees and woody plants to deposit their eggs. While this doesn’t directly harm most garden plants, it can lead to damage in orchards or areas with a high density of trees. This can be problematic in younger (2-4-year-old) trees. The best way to protect these young trees is to cover them in a mesh fabric for the ~1-month period when the cicadas are active. Mesh bags can be made from a variety of materials as long as the holes are smaller than 1 cm (~3/8 inch). Drape the fabric over all the twigs and branches that are smaller than 3/8 inches and secure it at the bottom so that cicadas cannot climb up from underneath. The goal is to prevent the cicadas from having access to the branches so that they will lay their eggs elsewhere.

Once the eggs are deposited, they hatch into nymphs that drop to the ground and burrow into the soil. The nymphs then feed on the sap from plant roots and undergo several molts as they grow. After spending several years underground, depending on the species, the mature nymphs emerge from the soil, climb a vertical surface (such as a tree or a structure), and undergo the final molt to become winged adults. The adult cicadas then mate, and the cycle begins again when the females lay their eggs in suitable host plants.

During the emergence, you will also see the exoskeleton remnants affixed to trees and branches. These pose no harm or threat to the plant and can simply be brushed off. You will also see the Cicada’s emergence holes in the ground. While the nymphs are in the ground they feed on the sap from roots, but damage from their feeding is likely minimal and probably unnoticed.

It’s important to note that while cicadas can cause some stress to plants, they are not typically considered a major threat to the health of well-established, mature plants. Additionally, different species of cicadas have different host plant preferences, so the impact on specific plants may vary.

This historic double emergence of the Cicada will not happen again in our lifetime. Embrace this example of the beauty of the natural world–even if here in Transylvania County we will only experience one brood. While there will be some disruption, a bit of noise, and lots of insects flying around, this will be a true example of the life cycle. It’s also worth mentioning that cicadas are a natural part of many ecosystems, and their periodic emergences are essential for the ecosystem’s balance. While they may cause temporary disturbances, they generally do not cause long-term damage to healthy, established plants–so embrace and enjoy.

Steve Matadobra is a certified Master Gardener with Transylvania County. He is also an avid wildlife and nature photographer and Vice President of the Transylvania County Bird Club.