West Cook News

Riverside is set to witness a natural spectacle this spring as Brood XIII, a group of 17-year periodical cicadas, emerges. This rare event, anticipated to take place from late May to early June 2024, will introduce millions of cicadas into the community, filling the air with their unique buzzing chorus.

Brood XIII comprises species such as Magicicada septendecim, renowned for their synchronized mass emergence. These cicadas have spent the past 17 years underground as nymphs, feeding on tree roots. Once the ground temperature reaches approximately 64 degrees Fahrenheit, they will surface, molt into adults, mate and lay eggs. This completes their life cycle in just a few weeks.

Although periodical cicadas do not pose a threat to humans or animals, they can cause damage to young trees. Female cicadas lay their eggs in small branches leading to a condition known as "flagging," where affected branches die off. This poses particular concern for newly planted or young trees.

There are several ways to protect your trees from potential cicada damage:

- Netting: Cover young or vulnerable trees with fine-mesh netting to prevent cicadas from laying eggs in the branches. Ensure the netting is applied by early May and removed once the cicada activity has ceased.

- Planting: Consider delaying new tree planting until fall to avoid potential damage.

- Insecticides: The use of insecticides is generally not recommended as they are ineffective against cicadas and can harm other beneficial insects.

Residents should prepare for the sight of cicadas on trees, shrubs and other surfaces. The males' mating calls will fill the air during this time and while their presence might be overwhelming, it’s a temporary phenomenon lasting only 4-6 weeks.

This event offers an opportunity to witness one of nature's incredible events up close. Despite its potential inconvenience, it's an occasion for observing these fascinating insects and educating children and community members about cicadas. This can foster a greater appreciation for our local ecosystem.

For more detailed guidance on how to protect your trees, visit the Morton Arboretum's Cicada Page.