An introduction toOplismenus undulatifolius(Ard.) Roem. & Schult. (wavyleaf basketgrass), a recent invader in Mid-Atlantic forest understories1,2

Abstract

A critical aspect of early-stage invasive species management is determining the niche and assessing the impact of a new species. A multi-scale strategy to predict potential habitat and impacts at the ecosystem, community and species level presents a robust, efficient, and cost effective tool for invasive species management. Regional scale maximum entropy modeling and local scale field studies were used to characterize species-environment and species-species interactions of Oplismenus undulatifolius, a recent invader in Mid-Atlantic forest understories. Oplismenus undulatifolius was first discovered in the U.S. near Baltimore, Maryland in 1996 and is currently found in 13 counties in Maryland and Virginia. At the landscape scale the USDA estimates that 30 percent of the U.S. is suitable for the establishment of O. undulatifolius. Regional scale modeling indicated that 22% of the area modeled was suitable for O. undulatifolius, with 1% highly suitable. Local scale field studies indicated that O. undulatifolius thrives at low light levels (2–11 mols m−2 day−1) across a wide range of litter depths (0–6 cm) and that light and litter depth are involved in dominance of O. undulatifolius over Microstegium vimineum. Interactions with Fagus grandifolia result in decreased O. undulatifolius cover and dominance, and areas of high O. undulatifolius cover typically have low species richness. Oplismenus undulatifolius has the ability to invade a far greater portion of the forest than M. vimineum, and more research on the community and ecosystem-level effects of this new invasive forest understory species is needed.