Natural Ways to Protect Trees from 13-Year Periodical Cicada Injury

The 13-year periodical cicada is a remarkable insect known for its synchronized emergence every 13 years. While fascinating, these cicadas can cause significant damage to young trees and shrubs during their mass emergence. If you live in an area expecting a cicada emergence, understanding how to protect your trees naturally is crucial. This article explores effective, eco-friendly methods to safeguard your trees from cicada injury without resorting to harmful chemicals.

Understanding 13-Year Periodical Cicadas and Their Impact on Trees

Periodical cicadas (genus Magicicada) spend most of their lives underground as nymphs feeding on tree root sap. After 13 years, they emerge en masse to mate and lay eggs in tree branches. The females use their ovipositors (egg-laying appendages) to slit small branches and twigs, inserting eggs into these slits. This behavior, called “flagging,” causes the tips of branches to wither and die.

While mature trees typically survive these attacks with minimal long-term damage, young or small trees can suffer severe injury or even death. The damage reduces growth, weakens branches, and increases susceptibility to disease and other pests.

Why Choose Natural Protection Methods?

Some landowners may consider chemical pesticides; however, insecticides are generally ineffective against periodical cicadas because of their brief above-ground adult phase and high numbers. Moreover, widespread insecticide use can harm beneficial insects like pollinators and disrupt ecosystems.

Natural protection methods offer several benefits:

Eco-Friendly: They avoid chemical residues that can harm soil, water, and wildlife.
Sustainable: They promote health and resilience of trees.
Cost-Effective: Most require minimal investment.
Safe: Reduced risk to humans, pets, and beneficial insects.

With this in mind, here are some proven natural approaches to protect your trees.

1. Physical Barriers: Netting and Screens

The most effective way to prevent cicadas from damaging tree branches is using physical barriers that block their access.

How It Works

Cicadas are unable to penetrate dense mesh coverings placed around young trees during their active period. Netting prevents females from reaching twigs to lay eggs.

Materials Needed

Fine mesh netting (such as garden or bird netting) with holes smaller than 0.25 inches (6 mm).

Soft ties or string.
Stakes if necessary for support.

Application Tips

Cover entire young trees or shrubs before cicadas begin emerging.
Secure netting firmly at the base of the trunk so adults cannot crawl underneath.
Ensure coverage is maintained throughout the active period (typically several weeks in spring).

Remove netting carefully after cicada activity ends to avoid trapping other wildlife.

Advantages

Immediate protection.
Reusable year after year.
Non-toxic and safe around children and animals.

Limitations

Can be labor-intensive for large numbers of trees.
May slightly reduce light penetration if not properly installed.

2. Tree Wrapping and Banding

Wrapping trunks with smooth materials like plastic tree guards can deter nymphs climbing out of the ground or adults climbing up trees but is less effective against egg-laying on branches. However, it can help protect very young saplings by limiting physical damage during emergence.

Suggested Materials

Tree wrap paper or plastic guards.
Burlap strips (used cautiously).

Apply wraps loosely without restricting growth; remove after cicada season ends to prevent moisture buildup that encourages fungal infections.

3. Pruning Damaged Branches Post-Emergence

Although this method is reactive rather than preventive, timely pruning has natural benefits:

Removes damaged “flagged” branches where eggs were laid.
Encourages healthy new growth.
Minimizes potential secondary infections entering through damaged tissue.

Best Practices for Pruning

Wait until after egg hatching when damage becomes visible (usually late spring or early summer).
Use clean, sharp pruning shears or loppers.
Cut back flagged branches at least 6-8 inches below egg sites.

Dispose of pruned material away from the garden area to reduce chances of spreading pests or disease.

4. Encouraging Tree Health Through Proper Care

Strong, healthy trees recover faster from cicada damage and withstand stress better than weakened ones. Adopt good horticultural practices:

Watering

Keep soil moist but not waterlogged, especially during dry periods before cicada emergence.

Mulching

Apply organic mulch around tree bases (2-3 inches thick) to retain moisture and regulate soil temperature but keep mulch away from direct trunk contact to prevent rot.

Fertilization

Use balanced organic fertilizers such as compost or well-rotted manure in early spring to promote vigorous growth without excessive nitrogen which may make trees more attractive targets.

Avoid Stress Factors

Limit unnecessary pruning or transplanting near emergence time as added stress makes recovery harder for affected trees.

5. Plant Resistant or Less Vulnerable Species

Some tree species exhibit natural resistance or tolerance to periodical cicada injury. When planting new trees in cicada-prone regions, consider species that cope better with egg-laying damage:

Oaks (Quercus spp.)
Dogwoods (Cornus spp.)
Maples (Acer spp.)

Avoid highly susceptible species like fruit trees (apples, peaches) during heavy emergence years or take additional protective measures if planting these varieties.

6. Foster Natural Predators and Biodiversity

Maintaining biodiversity encourages natural predators that help control cicada populations indirectly by preying on vulnerable stages or competing insects:

Beneficial Predators Include:

Birds such as blue jays, crows, and robins
Small mammals like squirrels
Spiders and predatory insects including praying mantises

How to Encourage Predators Naturally:

Provide bird feeders and water sources.
Plant native flowering plants to attract beneficial insects.
Avoid broad-spectrum insecticides that kill predators indiscriminately.

7. Monitor Cicada Emergence Timing Locally

Knowing when cicadas will emerge allows you to prepare timely protection measures such as installing netting just before adults surface, usually when soil temperatures reach about 64degF (18degC) at a depth of 8 inches (20 cm).

Local cooperative extensions or university entomology departments often provide detailed regional predictions based on soil temperature data.

Conclusion

While the mass emergence of 13-year periodical cicadas can be concerning for tree owners due to potential damage from egg-laying behavior, numerous natural strategies exist for protecting your valuable trees. Combining physical barriers like fine mesh netting with vigilant tree care practices builds resilience in your landscape while preserving ecological balance.

By using environmentally sustainable methods such as netting young trees, pruning damaged limbs post-emergence, promoting overall tree health through proper watering and mulching, planting resistant species, and supporting natural predators, you can minimize cicada injury effectively without resorting to harmful chemicals. Careful planning ahead of expected emergences ensures your trees survive the fascinating but challenging cicada cycle intact, returning strong for decades until the next event arrives.

References:

University Extension Publications on Periodical Cicadas
USDA Forest Service Guides on Cicada Damage Management
Peer-reviewed studies on Magicicada ecology
Organic gardening resources on integrated pest management