Leaves and branches slow the rate of rain hitting the ground, and roots help prevent soil erosion.
During downpours, rainwater can wash away soil and carve small gullies in people's yards and gardens. And it can overwhelm stormwater systems, flooding city roads and sidewalks.
But there's a simple way for cities and towns to reduce the risk of flooding - planting trees.
A tree's leaves and branches catch some of the rain as it falls, so less hits the ground. And what does trickle through falls more gently, instead of slamming into the soil and causing erosion.
Under the tree, fallen leaves and vegetation also trap some of the water, so less rushes into storm drains all at once.
And a tree's roots can also help. By snaking through the dirt, tree roots aerate the soil, which enables more water to soak underground instead of pooling on the surface. And by holding the soil in place around them, tree roots help reduce erosion during heavy storms.
Research by the nonprofit Climate Central has estimated that trees help prevent nearly 400 billion gallons of runoff each year across the United States.
As the climate warms, heavy downpours are becoming more common in many parts of the country, so the flood-preventing powers of trees are increasingly important.
Reporting credit: Ethan Freedman / ChavoBart Digital Media
This article first appeared on Yale Climate Connections and is republished here under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.