Are Bush Cicadas Harmful to Plants and Trees?

Cicadas are fascinating insects known for their distinctive buzzing sound and periodic mass emergences. Among the various types of cicadas, bush cicadas are a common sight in many gardens, woodlands, and rural areas. While they contribute to the natural ecosystem in many ways, gardeners and plant enthusiasts often wonder: Are bush cicadas harmful to plants and trees?

In this article, we will explore the biology of bush cicadas, how they interact with plants and trees, and whether their presence poses any significant threat to your greenery. We will also discuss how to manage or mitigate any potential damage caused by these insects.

Understanding Bush Cicadas

Before diving into their impact on vegetation, it’s essential to understand what bush cicadas are.

What Are Bush Cicadas?

Bush cicadas belong to the family Cicadidae, a group of insects characterized by their stout bodies, broad heads, clear wings, and loud mating calls produced by males. Unlike some other cicada species that emerge in large broods every 13 or 17 years, bush cicadas often have shorter life cycles and tend to be more regularly visible year after year.

They typically reside in bushes, shrubs, and trees—hence the name “bush cicada.” These insects feed on plant fluids by piercing stems or branches with their specialized mouthparts.

Life Cycle of Bush Cicadas

Understanding their life cycle is crucial for assessing their potential harm:

• Egg Stage: Female cicadas lay eggs in slits they cut into small branches or twigs.
• Nymph Stage: After hatching, nymphs drop to the ground and burrow into the soil where they feed on root sap for several years.
• Adult Stage: Once mature, nymphs emerge from the soil, molt into adults, mate, lay eggs, and die within a few weeks.

The length of the nymph stage varies among species but typically ranges from 2 to 5 years for many bush cicadas.

How Bush Cicadas Interact With Plants and Trees

The relationship between bush cicadas and plants is complex. While they depend on plants for nutrition and reproduction, their activities can cause varying degrees of impact.

Feeding Behavior

Both nymphs and adults feed on plant sap:

• Nymphs feed underground on root xylem vessels.
• Adults feed above ground by inserting their mouthparts into stems or branches.

This feeding usually does not kill plants outright but may stress them, especially if populations are high.

Egg Laying Damage

One of the most notable ways bush cicadas affect trees is through egg laying:

• Females use their ovipositor (a sharp appendage) to cut slits into small branches or twigs.
• They deposit eggs inside these slits.
• This process can cause twig dieback or “flagging” where branches turn brown and die.

The damage is generally confined to small branches but can be unsightly or problematic for young or weak plants.

Are Bush Cicadas Harmful to Plants and Trees?

The short answer is: They can cause some damage but are rarely harmful enough to kill mature plants or trees.

Let’s break down this assessment further:

Minor Physical Damage

Egg laying causes physical wounds on twigs which may lead to:

• Premature branch death (flagging).
• Reduced growth in affected twigs.

However, because egg-laying usually targets smaller branches rather than main trunks or large limbs, the overall structural integrity of mature trees remains intact.

Stress From Feeding

Feeding by adults and nymphs extracts sap from plants:

• Adults primarily feed on twigs and branches; heavy infestations might weaken parts of the plant.
• Nymphs feeding on roots can stress young or potted plants more than established ones.

Despite this sap removal, most healthy plants tolerate it well without long-term effects.

Impact on Young Plants

Young trees or shrubs with thin bark are more vulnerable to damage from egg laying and feeding:

• Repeated attacks can stunt growth.
• Heavy infestation may increase susceptibility to secondary infections or pests due to open wounds.

Gardeners should monitor young plants during cicada seasons for signs of damage.

Disease Transmission

Unlike some other insects such as aphids or leafhoppers that transmit plant diseases, there is no evidence that bush cicadas spread viral or bacterial pathogens to plants.

Their feeding is relatively benign from a disease perspective.

Ecological Benefits of Bush Cicadas

While bush cicadas may cause minor plant damage, they provide valuable ecological services:

• Soil Aeration: Nymph burrowing aerates soil around roots.
• Nutrient Cycling: Post-mortem decomposition returns nutrients to soil.
• Food Source: They serve as prey for birds, mammals, reptiles, and other insects.
• Pollination: Some incidental pollination benefits occur as adults move among flowers.

These benefits often outweigh their minor drawbacks in natural settings.

Managing Bush Cicada Damage in Gardens

If you find bush cicada damage concerning in your garden or orchard, here are management tips:

Monitor Populations

• Regularly inspect twigs for egg-laying scars during late summer when adult females lay eggs.
• Check for twig flagging indicating egg insertion sites.

Prune Damaged Branches

• Remove heavily infested or dead twigs during winter pruning.
• Proper disposal (burning or bagging) prevents larvae from overwintering in cuttings.

Protect Young Trees

• Use physical barriers such as garden netting around young trees during peak emergence periods.
• Avoid planting susceptible species prone to twig dieback where cicada populations are high.

Avoid Chemical Control

Pesticides generally offer limited effectiveness due to cicada life stages underground and above ground:

• Broad-spectrum insecticides may harm beneficial insects.
• Use chemical control only as a last resort under professional advice.

Encourage Natural Predators

Promote habitats for birds and predatory insects that help keep cicada populations balanced naturally.

Conclusion

Bush cicadas are an intriguing part of the ecosystem with unique life cycles and behaviors. Although they do cause some minor physical damage through egg laying and feeding, this rarely results in serious harm or death to mature plants and trees.

For gardeners concerned about young plants or ornamental bushes, monitoring and preventive pruning can minimize aesthetic impacts. In most cases, allowing bush cicada populations to maintain their role in nature without aggressive intervention yields the best balance between pest control and ecological health.

Understanding these insects helps us appreciate their place in our environment while managing any occasional nuisances wisely. So next time you hear that familiar buzzing from nearby bushes, remember: bush cicadas are more friend than foe when it comes to your plants!