Background
Florida scrub is a rare and rapidly disappearing community that can be found on dry, sandy soils lying within a matrix of associated xeromorphic plant communities (longleaf pine sandhill and xeric hammock [a forest type dominated by broadleaf evergreens]) and surrounding wetland areas (United States Fish and Wildlife Service [USFWS] 1995). All of these associated ecosystems are dependent on fires for persistence and are interconnected physiographically. These communities are found on a number of military installations where they support a variety of uses, such as the Department of Defense (DoD) training and testing mission, threatened, endangered and sensitive species (TES)* conservation, and recreation/open space. Some scrub may sustain intense land-use pressures, while other areas may serve simply as a buffer zone between military operations and civilian lands. Despite the fact that the primary mission of the DoD is military training and testing, installa tions are required to maintain robust populations of TES species into the foreseeable future.
Historically, management practices that protect TES, plant communities, and other natural resources reflected the need to address immediate and local problems. Although this approach can be rewarding and effective for an individual installation, it precludes any organized understanding of land-use impacts, or sharing of lessons learned, and can sometimes lead to repeated, inefficient efforts to solve similar problems throughout a region of the country. Duplication of effort needs to be reduced or eliminated.
This report is one product of an inter-laboratory effort between the U.S. Army Construction Engineering Research Laboratories (CERL) and the U.S. Army Engineer Waterways Experiment Station (WES) to generate habitat-based management strategies for TES on DoD lands in the southeastern United States (Strategic Environmental Research and Development Program [SERDP] work unit"Regional Guidelines for Managing T&E Species Habitats"; Martin et al. 1996). This effort is directed at developing strategies to manage TES and their habitats on a plant community basis, using methods that apply to multiple species and that apply across the southeastern United States. Any increase in understanding of the habitat requirements of listed TES will assist training and natural resource personnel in complying with the Endangered Species Act (ESA), while giving them the information they need to reduce restrictions on the military mission. Further more, the results detailed in this report suggest that a great deal of additional effort is required before the process will be guided by solid scientific information (as required by the ESA).
Objectives
The objectives of this research were to compile known information, identify gaps in knowledge, and stimulate future research efforts on the potential positive and negative effects of human activities on the plant communities that serve as high-quality habitat for TES in the southeastern United States.
This SERDP work unit, in particular, was undertaken to reduce duplication of effort towards conservation of TES within the southeastern region. It is intended that this review of information be used to improve the ecological and economic effectiveness of TES habitat management. By understanding the ecological requirements of TES and the environmental resilience or sensitivity of TES habitats, installations acquire increased control over TES management and land-use decisions.
Approach
To identify potential impacts, researchers reviewed the available literature and conducted interviews with community ecologists throughout the southeastern United States, with an emphasis on interviewing those people who have been involved in plant TES and plant community survey work on military installations. Potential impacts were also discussed with military natural resources personnel, botanists, community ecologists, and military contractors, and the staff at other environmental organizations, such as The Nature Conservancy (TNC) or state Natural Heritage Program (NHP). Information also was taken from installation TES survey reports in which impacts and management were addressed. Land Condition Trend Analysis (LCTA) data, Land Rehabilitation and Maintenance (LRAM) reports, and academic and Federal agency literature on recreational effects on plant communities were also reviewed.
Scope
Within the context of the larger DoD mission, TES populations can be maintained through the following framework: (1) identify mission requirements, (2) identify TES requirements, (3) identify ideal compromises for meeting both TES and mission requirements, and (4) pursue these compromises and develop realistic, workable plans. The fourth step should be executed through professional management of TES populations, at the installation level, to reduce restrictions on the military mission. This document partially contributes to the total TES and land management process. It provides information to assist in identifying the needs of TES (step 2), and perhaps will assist in identifying options for compromise as well (step 3). The content of this report is not intended to provide the "bottom line" for management of TES on military lands - only to provide information from literature review for the consideration of installation land managers.
This report focuses on plant communities because they provide habitat for multiple species. By managing for plant communities, DoD has the opportunity to conserve multiple TES simultaneously. Plant communities are less ambiguous entities than complete ecosystems, and have been described and cataloged for many decades by ecologists and biogeographers. They provide a useful basis on which to understand and manage the natural systems that support military training and other land uses.
Scrub communities are closely associated with xeric longleaf pine sandhills and other pyrogenic plant communities. Earlier reports from this SERDP work unit include summaries of management recommendations for a number of these associated communities (Harper et al. 1997 and Harper, Trame, and Hohmann, 1998). While conducting research for this report, researchers found management recommendations pertaining to species inhabiting both scrub and longleaf pine woodlands that tended to be biased toward longleaf pine. Some of the species mentioned herein, particularly the vertebrate TES, are found in several other community types that may or may not be associated with Florida scrub. However, any management recommendations that pertain to these organisms are written solely within the context of ecosystem management for the scrub community.
The intent of this document is to provide managers with the information needed to develop community-based, site-specific management plans for Florida scrub on installations within the state of Florida. An assessment of impacts has been provided. Based on this assessment and the current quality of the community, recommendations for management, restoration, and land use have been provided.
Due to the scope of this report, specific recommendations are intended to be considered only for areas that trainers and resource managers recognize and manage as endangered species habitat. These recommendations are not intended to be applied across entire DoD installations (e.g., on areas required for use as maneuver training zones).
Mode of Technology Transfer
This report is to be used by DoD natural resource policy makers, installation land managers, and the natural resource research community, in conjunction with associated documents produced under this SERDP work unit (e.g., Trame and Harper 1997; as well as Trame and Tazik 1995) to (1) develop ecosystem-based approaches to describe natural communities and TES habitat in relation to military activities, (2) evaluate military-related effects on those communities, (3) develop community-based strategies for supporting both military land use and TES habitat management, and (4) develop management solutions for military impacts to natural communities when management for TES habitat is a priority for a particular location.
Results of this report will be presented at the annual SERDP Symposium. In addition, this and companion volumes have been identified for life-cycle technology demonstration and support in the Conservation Technology Infusion effort being developed under the Army's environmental science and technology process.
* The acronym "TES" instead of "T&E Species"will be used in this report to conform to standard DoD terminology. We also include Candidate Species (former C1 Species), defined as those plant and animal species that, in the opinion of the United States Fish and Wildlife Service (USFWS) or National Marine Fisheries Service, may qualify for listing as threatened or endangered pursuant to the Endangered Species Act; and Species of Concern, or former C2 species.