Cicadas are coming; It’s not a big deal – it’s amazing.
In our area we have cicadas every year. We can hear them on hot July and August days calling out for mates. But every 17 years we are witnesses to one of nature’s truly amazing mysteries, and this is the year with the emergence of the Brood X cicadas. These insects will appear after living underground for 17 years, as nymphs, feeding on root sap. In late May or early June, when the soil temperature reaches 64 degrees, they emerge to climb the nearest things to molt for the last time, mate and start the cycle all over again. The good news is adult cicadas do not cause significant feeding damage, since adults do not feed on leaves. If they feed at all, it is by sucking plant fluid from tender young twigs. They are also not a threat to people at all, because they don’t bite or sting.
The only damage cicadas cause to plants results from the egg laying habits
Female cicadas use an appendage, called an ovipositor, to gouge longitudinal slits in twigs into which they then deposit eggs. While mature trees and shrubs usually handle even dense emergences without long-lasting effects, the younger trees and shrubs may suffer some damage if too many feed on them or lay eggs in their twigs.
So, what should you do? Here are a few tips from the University of Maryland. If you would like to check out the full article it can be found here; Extension.umd.edu/hgic/topics/cicadas.
Control is not necessary on established trees.
Insecticides are ineffective for significantly reducing cicada abundance and damage. Insecticides also pose a risk to people, pets, beneficial insects, and birds.
If you intend to plant trees or shrubs in a year when periodical cicadas emerge, consider delaying planting until fall when the cicadas are gone.
Small ornamental trees, shrubs, and fruit trees may be protected by covering them with plastic mesh (<1/2 inch openings) that is sold in garden supply centers. Tulle is a readily available fabric that can draped over small or newly planted trees and shrubs and held to the ground with rocks, bricks, or landscape pins. The plants should be protected from the time cicadas emerge until they are gone 6-8 weeks later.*
Ornamental ponds should be covered with screening or plastic mesh to prevent cicadas from accumulating. Large numbers of decomposing cicadas could cause problems with oxygen depletion in the water.
Clean pool skimmers/filters frequently during cicada emergence to keep them from getting clogged.
*Some experts suggest using smaller mesh or netting so as not to trap birds.
Covering younger trees and shrubs with a mesh netting allows air to continue flowing and precipitation to reach the plant while protecting the plant. Another method of wrapping trees is the “lollipop” method. Drape the mesh over the tree like a wrapper over a lollipop. Then take small zip ties to knit the open sides together. Gather the mesh at the base of the tree using a larger zip tie to fit the circumference of the tree. One source for insect netting is Insect Netting For Garden | Agfabric.
The mesh can be removed in late June or July after the cicadas have gone. You will know it’s time when the quiet returns. The website Periodical Cicadas has an up-to-date map of cicada sightings and information on cicada Broods and citizen science projects.