URBANA – Summer storms have damaged trees, some more than 100 years old, in communities across the state. Homeowners in theses communities, including Woodridge and Naperville which were hit by an EF-3 tornado this spring, are now struggling to find the best ways to clean up after a tree is damaged and the proper way to restore trees in their communities.

From watching the light flicker through a tree's green canopy in summer to enjoying the falling cascade of red, yellow, and brown leaves in the fall, trees serve as a symbol for many homeowners. Storms can damage or destroy long-living trees and the memories they carry with them.

What happens after a storm damages trees?

Get The Latest News!

Don't miss our top stories and need-to-know news everyday in your inbox.

When a tree becomes damaged by a storm, or another type of disturbance, it not only affects the immediate area, but also the surrounding trees.

“Trees are usually very resilient to damage,” says University of Illinois Extension horticulture educator Ryan Pankau. “But when a storm or disease takes out parts of a tree, it exposes the other trees in the area differently, and you may see damage to them years down the line.”

After a disturbance, sunlight can now reach the understory, which exposes the soil and creates opportunities for new plants to fill those gaps. Those gaps can be filled by younger trees or plants, but also by less desirable plants, such as invasive weedy species. And, a thinning tree canopy from storm damage can reduce a tree's capacity to filter wind.

“Trees with thicker canopies act like a sail during high winds,” says Christopher Enroth, Illinois Extension horticulture educator. “But when thinned, small, new branches have a very weak attachment to the tree itself, making it less stable overall.”

How to select and replant trees

“The most important thing to consider when replanting trees after a storm is diversity,” says Extension Forester Chris Evans.

Planting a variety of new trees, especially native trees, recreates a natural ecosystem, and leads to fewer pest issues, diseases, and invasive species.

Replacing damaged trees with native ones will add to the biodiversity of that area, letting insects, birds, and other organisms flourish in a healthier ecosystem. A study published in the journal Ecological Entomology in 2020 found the displacement of native plant communities is the main cause of a collapse in insect and bird populations around the world. To see if a tree is native, check at the USDA-approved hardiness zones located on the plant tag or online at planthardiness.ars.usda.gov.

Research specific species to see if it would be a good fit for your landscape and ask a certified arborist for verification. Some species, such as oak trees, have a competitive advantage. Compared to shady beech and maple trees, oak trees will take 40% to 60% of the available sunlight to compete with other plants and leave other species to die off.

Why should you replace trees?

When trees are knocked down, it can change a community. Wildlife no longer has a place to nest, children lose a place to play, and homes are no longer shaded from the summer heat.

Trees provide a lot of unappreciated services in the background. They create habitat for insects, birds, and other native wildlife, and take up water which reduces flooding impacts. They also increase an area’s air quality and trap carbon dioxide, a greenhouse gas, to slow the rate of global warming. In the warmer months, trees that shade homes will reduce energy bills and in the winter months, bare branches allow sunlight to heat homes.

Of all green spaces, trees seem to have a special impact on people’s mental health. Research from University of Illinois has found that when people have experiences with nature, they're healthier, happier, learn better, and have stronger social ties. Green spaces are also tied to lower rates of depression and anxiety disorders.

“We, as humans, are meant to be in nature, and when you put us in an environment that takes it away, we behave and feel badly,” says Pankau.

How can homeowners respond to a disturbance?

After a storm has passed and the scene is safe, the first thing to do is clear out the obvious broken, hanging limbs. Then, look at the angle of the leaves on branches still attached to the tree, as they will give away tree limbs that might be broken and could fall later.

Avoid areas with downed power lines, as they may still be active and are very dangerous.

“The next course of action is to have a tree care professional or a certified arborist assess the damage,” says Article continues after sponsor message