At the corner of 16th and Race streets, insects are multiplying.
While it's hard to track official numbers, the Pennsylvania Department of Agriculture says reports and sightings are up 500% compared to last year.
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They aren't harmful to people, but they do destroy crops and vegetation.
And while no one knows quite why they love the city so much, it seems they're not very welcome here.
State officials say you can do your part. If you see them, they ask that you stomp on them.