Ah, it’s fall foliage season. For my money, there’s no more beautiful season in Iowa than when the trees start changing colors. But this year, many people are noticing something unusual in the trees – odd grey tent-like structures, covering up much of the beautiful foliage. This is the work of an species of moth, known as the fall webworm, with a taste for leaves and a very distinctive decorating style. While the moth isn’t considered an invasive species – it’s native to North America – it’s become a fast-growing pest that is considered a risk for defoliation. While these unsightly additions to our hardwood trees aren’t likely to kill the trees, many people are wondering – is this a permanent addition to fall foliage season? Here’s everything you need to know about the fall webworm in Iowa.

As you criss-cross the Hawkeye State, it's impossible to avoid the sight of beautiful fall foliage - but some trees are looking a little different.
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Those strange tent-like structures that appear in trees are the work of the fall webworm, a species of moth that spins protective nets over tree branches as they devour the leaves.
Alison Hunter/Wikipedia
Each of these nets contains countless caterpillars, each busily munching away.
Alison Hunter/Wikipedia
Eventually, the caterpillars will become moths like this one, which aren't any danger to the leaves they heartily consumed as a larva.
TampAGS/Wikipedia
The favored dining options of the fall webworm are hardwood trees - which just so happen to be the ones that display the most stunning fall foliage.
Bruce Marlin/Wikipedia
The good news is, the only effect these moths have on trees is defoliation, which is unsightly but not damaging in the long term. Still, if you wish to get rid of these moths in your tree, the Iowa DNR recommends using a stick to cut open the silk net, exposing the caterpillars to the many predators out there.
Carlos Lopez-Vaamonde/Wikipedia

Have you spotted the telltale signs of the fall webworm in Iowa? Tell us about where you’ve seen their handiwork, and let us know your favorite spots for viewing fall foliage in Iowa in the comments section. You can find out more about the fall webworm in the official Iowa DNR press release. If you’re planning any fall foliage hikes this year, make sure to subscribe to AllTrails Plus for interactive trail maps and other features.

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