Invasion Ecology and Response to Fire of the Nonnative Fern Lygodium microphyllum in the South Florida Everglades

Abstract

Lygodium microphyllum (Old World Climbing Fern (OWCF)) is a climbing fern native to tropical and subtropical regions of Australia, Asia, and Africa. First introduced to Florida as an ornamental in the 1960s, the fern has become a serious invasive in numerous Florida habitats, severely degrading native herbaceous and woody vegetation and altering fire behavior. One area with the greatest increase in OWCF cover is the sawgrass marsh of southern Everglades National Park (ENP), where prescribed fire is used for both maintenance of sawgrass marshes and management of OWCF infestations. However, the efficacy of OWCF control using fire in this habitat is uncertain. This dissertation investigated the response of individual OWCF plants in coastal sawgrass marshes over two years following a prescribed burn. As some OWCF occurs in brackish conditions, salinity tolerance of the fern was assessed under greenhouse conditions. Additionally, nectar production, which can influence biological control agent success, was examined in OWCF and related species.