It sounds like a decent setup for a horror movie: an area plagued with "extremely active, aggressive" worms that can jump a foot into the air and have "voracious appetites." That's a reality California is staring down right now, according to multiple reports on recent sightings of the Amynthas agrestis, which also goes by the names Asian jumping worm, Alabama jumper, and crazy snake worm, reports the Guardian. It hails from east Asia and was first identified in the US in 2013, having made their way here via imported landscaping plants.
They were spotted in California in July, and the state's Department of Food and Agriculture (CDFA) offers this unpleasant description of them: "True to their name, they jump ... and thrash immediately when handled, behaving more like a threatened snake than a worm, sometimes even breaking and shedding their tail when caught." But the worms' weird behavior isn't the concerning part; its destructive behavior is. While the CDFA notes that while earthworms are often "considered friends of the ecosystem due to their ability to loosen and aerate soil," that's most definitely not the case here. These worms can wreak havoc in hardwood forests thanks to their ability to rapidly eat their way through the leaves that blanket forest floors.
Many tree species "rely on thick layers of leaf litter that serve as rooting medium," per the CDFA, and the worms obliterate it, "turning the soil into grainy, dry worm castings that cannot support understory forest plants" (SFGate likens the aftermath to looking like "taco meat"). Suggested methods of dealing with the worms sound a bit involved: One is to handpick them from the earth, put them in bags, place the bags in the sun for a minimum of 10 minutes, and then deposit the bags in the trash. The other involves forcing the worms to the surface using a mix of water and yellow mustard seeds, then topping the soil with a sheet of transparent polyethylene for several weeks to drive up the soil temps and kill off the worms' cocoons. (Read more invasive species stories.)