Cicadas are large, periodic insects known for their synchronized, noisy emergence across eastern North America. They spend most of their lives underground as nymphs, surfacing en masse in annual or massive 13- or 17-year cycles to reproduce. While the sheer numbers and loud mating calls of adult males can be disruptive, cicadas do not sting or bite and pose no threat to humans or pets. The primary concern for most homeowners is the potential damage to young, vulnerable trees caused by egg-laying females. Understanding what naturally repels or preys upon cicadas provides the best framework for effective defense strategies during their brief time above ground.
Biological Threats and Natural Predators
The most effective “haters” of cicadas are the natural organisms that consume them or halt their reproduction. The sudden, overwhelming emergence of periodical cicadas is a feeding bonanza for nearly every local animal, a strategy known as predator satiation. Birds, squirrels, raccoons, bats, and fish quickly change their foraging habits to consume the protein-rich insects in large quantities.
A more specialized threat comes from the Cicada Killer Wasp (Sphecius speciosus). This large species paralyzes adult cicadas with a sting before dragging them back to its underground nest. The wasp lays an egg on the immobilized cicada, providing a meal for its larva upon hatching. Another biological enemy is the specialized fungus Massospora cicadina, which exclusively infects adult periodical cicadas. This pathogen turns the insect into a flying fungal spore dispenser by consuming the abdomen and reproductive organs. Infected male cicadas mimic female signaling, luring healthy males for attempted mating, which maximizes spore dispersal across the population.
Physical Protection and Barriers
The most reliable way to protect valuable plants from egg-laying damage is through physical exclusion. Female cicadas cause harm by using a saw-like ovipositor to slice into thin, pencil-sized branches and twigs to deposit their eggs. This action can cause the branch tip to brown and die, a condition known as “flagging,” which is detrimental to young saplings or ornamental trees.
Gardeners should cover vulnerable young trees, shrubs, and fruit trees with fine mesh netting or cheesecloth before the first cicadas emerge (when soil temperatures reach 64 degrees Fahrenheit). The netting should have a mesh size no larger than one-quarter inch (1/4″) to prevent adult cicadas from passing through. Securely tie the netting around the base of the trunk to prevent insects from crawling up underneath the barrier. Avoiding planting new trees or shrubs in the year preceding a known large-scale emergence is another effective strategy, removing susceptible plants from the landscape during the high-risk period.
Chemical and Scent-Based Aversion
The use of chemical sprays to repel cicadas is not recommended and proves largely ineffective. Adult cicadas emerge in such overwhelming numbers that spraying an area only provides temporary relief before new individuals move in. Broad-spectrum insecticides pose a greater threat to beneficial insect populations, including pollinators and natural predators, than the cicadas themselves.
Some anecdotal evidence suggests certain strong scents may temporarily deter cicadas from landing on treated plants. Essential oils like peppermint, eucalyptus, and lavender are cited as potential natural repellents when diluted and sprayed onto foliage. Garlic sprays and neem oil, an organic product that can disrupt an insect’s feeding and life cycle, are also used as contact-based deterrents. These natural solutions require frequent reapplication, especially after rain, since they break down quickly and do not offer the protection of a physical barrier.
Ineffective Repellents and Common Myths
Many methods people attempt to repel cicadas offer minimal to no actual protection. The belief that loud noises will drive them away is a myth, as the insects are naturally drawn to high-decibel sounds they interpret as mating calls. Operating loud machinery like lawnmowers or power tools can unintentionally attract swarms of cicadas to the area.
Simple household mixtures, such as water mixed with dish soap, are ineffective against adult cicadas. While insecticidal soaps can kill some soft-bodied insects, the sheer volume and large size of cicadas make this approach impractical for control. Attempting to use ultrasonic devices or relying on planting specific garden herbs to ward off the insects has not been scientifically validated as an effective deterrent. The best approach remains physical exclusion for young plants and waiting out the few weeks of the adult emergence.