Updated: July 6, 2025

Cicadas are fascinating insects that capture the attention of gardeners and nature enthusiasts alike, especially during their emergence periods. Among the various species, brown cicadas are commonly spotted around plants and gardens, prompting many to wonder: Are brown cicadas harmful to your plants? This article explores the impact of brown cicadas on plants, their lifecycle, behavior, and how to manage them in your garden.

Understanding Brown Cicadas

Brown cicadas belong to the family Cicadidae and are typically characterized by their large size, robust bodies, and prominent wings. They are often brown or tan in color, which helps them blend into tree bark and foliage. These insects are most famous for their distinctive loud buzzing or clicking sounds produced by males to attract females.

Unlike some garden pests that feed destructively on leaves or stems, cicadas have a unique feeding habit. They use their specialized mouthparts to pierce plant xylem—usually tree roots when young and branches or twigs as adults—to suck sap.

The Cicada Lifecycle and Plant Interaction

To understand whether brown cicadas harm plants, it’s critical to look at their lifecycle:

  1. Egg Stage: Female cicadas lay eggs in slits they make in small branches or twigs of trees and shrubs.
  2. Nymph Stage: After hatching, the nymphs fall to the ground and burrow underground, where they feed on root sap for several years (often 2-17 years depending on species).
  3. Emergence: Mature nymphs emerge from the soil, climb nearby vegetation, molt into adults, mate, and begin the cycle anew.

Potential Plant Damage by Cicadas

  • Egg-Laying Damage: Female brown cicadas use their ovipositors to cut slits in small branches to deposit eggs. This activity can cause “flagging,” where the ends of twigs die and droop. In large numbers, this can lead to twig dieback and stunted growth.

  • Feeding Damage: Both nymphs (feeding on roots) and adults (feeding on branches) extract xylem fluid from plants. While this does not typically kill plants, it may stress young or weak plants if infestations are heavy.

  • Physical Damage: The emergence of large numbers of cicada nymphs tunneling out of the ground can disturb soil structure around plant roots but generally does not cause significant harm.

Are Brown Cicadas Harmful to Your Plants?

The answer depends on several factors such as cicada population density, plant type, and plant health.

Generally Low Risk to Mature Plants

Most mature trees and shrubs tolerate cicada feeding well. The extraction of sap from branches and roots usually does not affect overall plant vitality significantly because:

  • Xylem sap contains relatively little nutrient value.
  • Healthy plants can compensate for minor losses.
  • Feeding sites heal over time without lasting damage.

Young Plants Are More Vulnerable

Seedlings or recently transplanted young trees can suffer more due to:

  • Stress from egg-laying damage leading to twig dieback.
  • Reduced root function caused by nymph feeding underground.
  • Overall decreased vigor making them susceptible to other stresses.

In these cases, cicada activity could slow growth or cause some dieback but rarely kills plants outright.

High-Density Emergence Can Cause Noticeable Damage

During mass emergences (such as periodical cicada outbreaks), thousands of cicadas may swarm an area causing:

  • Significant twig flagging due to egg-laying.
  • Increased feeding pressure on roots.
  • Larger disturbance in soil structure from nymph emergence tunnels.

These conditions increase the risk of plant stress but still seldom result in plant death unless combined with drought or disease stress.

Crop Plants and Orchards

Certain crop trees like fruit orchards may experience cosmetic damage reducing market value. For instance:

  • Egg-laying scars on fruit tree branches.
  • Temporary branch dieback affecting fruit production.

Farmers may need to monitor cicada activity more closely during major emergences.

Identifying Cicada Damage on Plants

Signs that brown cicadas might be affecting your plants include:

  • Dead or wilted twig ends (flagging).
  • Small egg slits or scars on young branches.
  • Sudden yellowing or wilting in very young plants.
  • Emergence holes in soil around tree bases.

Hearing loud buzzing sounds during warm months is also a strong indicator of adult cicada presence nearby.

Managing Brown Cicada Impact in Gardens

While brown cicadas generally cause minor damage that resolves naturally, certain steps can protect vulnerable plants:

1. Protect Young Trees

Wrap tree trunks with fine mesh nets during peak egg-laying periods (usually late spring to early summer) to prevent females from reaching twigs.

2. Prune Affected Branches

Removing flagged twigs after egg-laying reduces stress load on trees and can prevent secondary infections at damaged sites.

3. Maintain Plant Health

Strong, well-watered plants withstand feeding better. Avoid drought stress during emergence periods through appropriate irrigation.

4. Avoid Pesticides Unless Necessary

Most insecticides are ineffective against adult cicadas due to their short above-ground life span and widespread dispersal. Use chemicals only if absolutely necessary and with caution not to harm beneficial insects.

5. Encourage Natural Predators

Birds, spiders, and other predatory insects help control cicada populations naturally over time.

Conclusion: Should You Worry About Brown Cicadas?

Brown cicadas are largely harmless to established plants and trees. Their unique lifecycle means their impact is usually limited to minor twig damage during egg-laying and minimal feeding stress on plant sap.

However, young or stressed plants can experience noticeable damage that might require intervention such as physical barriers or pruning damaged twigs. Mass emergences increase risk temporarily but do not usually result in long-term harm if proper care is taken.

Understanding the habits of brown cicadas allows gardeners to appreciate these intriguing insects while minimizing any negative effects on prized plants. In most cases, patience and good horticultural practices are all that’s needed during cicada season!


By learning about brown cicadas’ behavior and potential impact on plants, gardeners can better manage their gardens without unnecessary alarm while supporting biodiversity.

Related Posts:

Brown Cicada