DIVERSITY | Offering a place for everyone
15 July 2008
Repelling the Invasives
From estuarine waters to the vast forests and valleys of public lands, to the gardens of everyday homes, plant species invasion is a major environmental problem in the United States and many other parts of the world.
It begins with the unwitting import, or the deliberate but ill-considered introduction, of a plant that comes from an entirely different ecosystem. Dropped into a new environment, without the natural controls of its own delicately balanced ecosystem, an exotic plant can choke out species native to an ecosystem, sometimes to the point of overwhelming them completely. In some cases, this invasion can threaten the very survival of native plants that are unique to the distinctive environmental conditions of a habitat.
The well-intentioned but environmentally unsound introduction of species to the American continent dates to the earliest years of European settlement, long before the biological and environmental consequences of such actions were understood. Full recognition of the invasive species problem in the national parks came in the 1960s with publication of the landmark Leopold Report, named for a prominent biologist who led a study of the parks’ ecological management.
Today, the National Park Service is tackling the invasive species problem with Exotic Plant Management Teams (EPMTs). EPMTs were established to provide a framework and a first response to exotic plant invasions in parks. The 16 teams are stationed across the United States, each serving a regional network of parks. EPMTs are playing an increasing role as regional experts in vegetation and invasive species management. Teams also assist parks with vegetation management plans and environmental compliance. Over the last five years, EPMTs have managed or treated more than 35,000 acres (some 14,000 hectares), worked in more than 200 parks, and treated more than 300 invasive plant species. Invasive plants are managed through a variety of control techniques -- including hand pulling, chemical, biological, and mechanical -- all with the objective of controlling the spread or reducing the density of growth.
The work of the teams has been bolstered by more than 25,000 volunteer hours in support of conservation. Likewise, the Student Conservation Association, a nationwide youth volunteer organization working to improve public lands, has been an important partner in this work to control invasive species.
The Park Service also enlists the aid of the youngest generation of park lovers to help control invasive species. A few months ago, NPS Director Mary A. Bomar was in Florida’s Everglades National Park with First Lady Laura Bush and a group of schoolchildren. The students helped remove Brazilian pepper, an exotic invasive species common around south Florida. While there, the students became honorary Junior Rangers and assisted park staff in planting 15 native trees and shrubs in the area.
