Cicada – Information and Control

Cicadas can be present in many areas of the country, they are a flying, plant sucking insect that emerges in periodic cycles called broods.

Periodic Cicadas (Top picture) emerge in a 13 or 17 year cycle. The adults have red to orange eyes, will be 1 to 1½ inches and emerge in late May or early June by the millions. Female periodic cicadas use a saw-like appendage on the abdomen to slice into 1/4- to 1/2-inch diameter tree twigs and deposit their eggs. The leaves on damaged twigs turn brown, and some twigs may die. This “flagging” can be quite visible in areas with large numbers of cicadas.

Annual Cicadas, aka dog day cicada, (second picture) emerge every 2 to 5 years, although there is a brood almost every year. These are up to 2 inches long and have dark eyes and green bodies, they emerge in the “dog days” of summer, July or August.

Cicadas usually emerge from the ground at night and you don’t see the emergence, but you will find the hard, empty exoskeleton attached to the sides of trees, buildings, etc. The adults mate and die within 2 to 4 weeks, but first, the females inject their eggs into slits in tree branches this is when they can do the most damage. Many of the damaged twigs will break off and drop to the ground, reducing yield if on fruit trees. Nymphs suck juices from the roots of plants.

Visit the pages linked below for more information on Periodical Cicadas.

Periodical Cicadas, Missouri Department of Conservation:
https://mdc.mo.gov/trees-plants/diseases-pests/periodical-cicadas

Periodical Cicadas Field Guide, Missouri Department of Conservation:
https://mdc.mo.gov/discover-nature/field-guide/periodical-cicadas

 

Control

The effect on mature trees is minor, so it is not usually necessary to use insecticides. For  trees or shrubs that are small enough, you can place small mesh (smaller than 1/4 inch) netting over the plant tying it closed around the trunk. Cheesecloth or mosquito netting will work for this. The netting must be tied and closed off on the trunk under the branches to keep the cicadas out. A band with adhesive wrapped around the trunk can trap the emerging nymphs as they crawl up the tree from around mid-May to late-June. The nymphs may need to be removed daily to keep the sticky surface open for new climbers to get stuck. This will help reduce their numbers, but adult cicadas that emerged on another tree or a building will still be able to fly onto your trees. You can also prune out and destroy young twigs that have been damaged by egg laying. Do this within a four-to-six-week period after eggs are laid. This will prevent newly emerged nymphs from reaching the ground.

Using insecticides is not good for the pollinators that help plants flourish and produce better. Cicada damage usually is not enough to kill a tree and, unless there is an unusual high number of them on one tree, it is not recommended to use insecticide. Additionally, cicadas are even considered beneficial because they prune trees, aerate the soil, and once the adults die and decompose, they add nitrogen to the soil. However, if you decide to use insecticide some options are included below.

Hi-Yield Indoor/Outdoor Broad Use Insecticide is labeled for control of cicadas. Spray trees and shrubs repeat at 4 to 8 day interval as needed, as long as you see adults.

Hi-Yield Bug Blaster Bifenthrin 2.5 can be used on Trees and Shrubs, repeat no sooner than every 7 days, as needed.

Bonide Eight is available in ready to use and concentrated formulas. Spray trees and shrubs wetting leaves to the dripping point. Repeat at 4 to 8 day interval as needed, as long as you see adults.

Note: when mixing concentrated insecticide products, using Hi-Yield Spreader Sticker additive will help improve adhesion and coverage of the product, which increases the effectiveness.

Read labels on all insecticides and follow the directions properly.