Identification and Management of Multiple Threats to Rare and Endangered Plant Species
RC-1542
Objective
Effect of deer herbivory on forest understory plants. Deer are excluded on the right of fence and have access to plants on the left.
Forests in the eastern United States have undergone dramatic changes, and many plant species now exist in isolated or small populations considered to be threatened, endangered, or at-risk. Threats to long-term survival range from general habitat loss and fragmentation to overabundant deer populations; invasive plants, animals, and diseases; acid rain; nutrient deposition; and climate change. Ideally, any management of plant populations or of various threats would be informed by (1) an analysis of the severity of a particular threat or of the cumulative threat posed by different stressors and (2) how a particular plant species/population responds to management of different stressors. Guidelines for such an approach are not available to land managers at military installations or elsewhere.
The objective of this project is to assess the importance of both biotic (deer herbivory and plant, earthworm, slug, and insect invasions) and abiotic (phosphorous and nitrogen levels) stressors on threatened and endangered (T&E) plant species. Specifically, this project aims to model the relative contribution of these stressors to plant demography; create “vulnerability indices” of select plant species to deer, slug, and insect herbivory as well as the influence of nutrient addition to the interaction of plants and their herbivores; and assess current and potential future threats resulting from stressor-induced changes in growing conditions and palatability.
Technical Approach
Life Table Response Experiments (LTRE) will be used to assess the role of various stressors on population growth rates of T&E plant species. Experimental manipulations of deer, earthworms, slugs, and root weevil abundance and invasive plants will be used to assess their contribution to the demography of select T&E plant species. Data obtained from these experiments, as well as monitoring at the field site, will be used in demographic modeling to identify the contribution of different stressors to population growth rates. In addition, feeding trials (using slugs, insects, and deer in the presence/absence of earthworms or with and without nutrient addition) with multiple native and introduced plant species will be used to explore the potential for creating “vulnerability indices” for select T&E plant species. This information will subsequently be used to determine whether plant nutritional traits and defense chemistry, which may change with earthworm presence/absence or changes in nutrient deposition, can explain the feeding preferences of deer, insects, and slugs. Restoration techniques using seed addition or transplants of well-established seedlings will be examined to assess the potential for restoration in the presence/absence of different stressors.
Benefits
At present, land managers have little quantitative evidence to support different management activities for T&E plant species. Should the focus be on deer management, management of invasive plants, prevention of earthworm invasions, or reductions in nutrient inputs? This assessment of the relative contribution of various stressors to several T&E plant species and their demography will illuminate the severity of single or combined threats and allow prioritization of efforts to address these threats in support of more cost-effective management of stressors. The reseeding and replanting experiments also will provide recommendations for plant restoration, where necessary. Together, these efforts will help maintain the ability of Department of Defense installations to protect natural resources while sustaining military missions. (Anticipated Project Completion – 2012)
Symposium & Workshop
FY 2013 New Start Project Selections
Points of Contact
Principal Investigator
Dr. Bernd Blossey
Cornell University
Phone: 607-255-5314 xCell 607.227.1572
Fax: 607-255-0349
Program Manager
Resource Conservation and Climate Change
SERDP and ESTCP
Document Types
- Fact Sheet - Brief project summary with links to related documents and points of contact.
- Final Report - Comprehensive report for every completed SERDP and ESTCP project that contains all technical results.
- Cost & Performance Report - Overview of ESTCP demonstration activities, results, and conclusions, standardized to facilitate implementation decisions.
- Technical Report - Additional interim reports, laboratory reports, demonstration reports, and technology survey reports.
- Guidance - Instructional information on technical topics such as protocols and user’s guides.
- Workshop Report - Summary of workshop discussion and findings.
- Multimedia - On demand videos, animations, and webcasts highlighting featured initiatives or technologies.
- Model/Software - Computer programs and applications available for download.
- Database - Digitally organized collection of data available to search and access.