This time of year, the feathery leaves of Bald Cypress trees, conifers that thrive in wet soil in the southeastern United States, begin to change to an intense bronzy orange color. But this lone cypress is surrounded by a noxious plant floating on the surface of the water that was only very recently discovered on Caddo Lake. In 2006, the Giant Salvinia, an invasive aquatic fern from Brazil that was first imported for use as an ornamental plant, was found in the lake. It can double its biomass in days and threatens the health of the ecosystem in which it thrives. Locals call it the “lake-eating monster.” Efforts to control the Salvinia have been partially successful and the introduction of a weevil that feeds only on Salvinia has been a potential solution that might eventually eradicate the problem.