A deceptively deadly force is slithering its way through the Florida Everglades. Sinuous and stealthy, this invasive species is one of the greatest threats to the ecosystem. And it’s not a python.

Old World climbing fern, Lygodium microphyllum, is arguably the worst of many invasive species in the Everglades.

“It grows quickly, spreads easily, and is changing the entire ecosystem,” says Kristina Serbesoff-King, the associate director of conservation for the Conservancy’s Florida chapter.