My first thought when looking at this photo (posted by Reddit user ILikeWhereThisIsGoin, who probably doesn’t) was “oh, a lawnmower must have exploded! Look at all those grass clippings. All those perfectly innocuous, not-alive grass clippings.” But no, that’s just thousands and thousands of mayflies. Still perfectly innocuous, in the sense that they won’t hurt you, but WOW a lot more gross.

Minnesota has been experiencing its worst mayfly season in a decade, with swarms so thick they make you seriously wonder whether someone misinterpreted the “locusts” part of the apocalypse. On one local highway, the four-inch-deep carpet of flies actually caused an accident, when a car slid on a mayfly slick and careened into another vehicle. A nearby town had to send out plows to shovel the bugs off the road.

Mayflies only live for a day or two, so at least Minnesota’s problem quickly shifted to dead mayflies instead of furiously rutting mayflies. But really, neither is great.

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Here’s a video: