The staff of Research Work Unit NE-4152, in Warren, Pennsylvania, conducts basic and applied forest ecosystem research to enhance understanding of Allegheny Plateau forests. We provide basic scientific understanding leading to management guidelines and management unit indicators for forest ecosystems in Pennsylvania, the Allegheny Plateau, and adjacent regions, focused on sustaining values of biological diversity, economic and ecological productivity, forest health and vitality, and contributions to carbon cycles. Our research is conducted in the Allegheny Plateau region, at the stand, stand aggregate, and landscape level. Through this regional research, we contribute to basic understanding of forest ecosystems and sustainable forest management.

RESEARCH PROBLEM AREAS... Forest Renewal The key to sustaining forests is successfully renewing all their elements after disturbance, across landscapes and through time. Our research is aimed at strengthening our understanding of the relationships among certain elements of forest communities in stands of different ages, species composition, and disturbance history. Specifically, we build on our databases and mechanistic understanding of woody and herbaceous plants, songbirds, small mammals, amphibians and forest carbon. Uunderstanding the factors that control regeneration and renewal of each of these communities, the responses of these communities to disturbance, and the impacts of selected disturbances on forest carbon pools and sequestration rates are critical. We aim to provide managers with tools to ensure diverse new forests, for a variety of management objectives. Stand Development and Intermediate Treatments Intermediate treatments, or non-stand-replacing disturbances, create predictable changes in forest conditions. Our goal in this problem area is to strengthen our understanding of the effects of intermediate treatments on wood production, wildlife habitat, herbaceous plant communities, and carbon sequestration, and develop associated guidelines and indicators of sustainability. Historically, intermediate treatments in forested stands have been undertaken primarily for their contribution to wood products objectives. We study the effects of these treatments on wood production, but as our understanding of the relationships between wildlife species and important habitat components increases, we recognize that intermediate treatments may also be used to promote specific kinds of wildlife habitat. Stress and nutrient relationships for Allegheny Plateau plant species Our research on sugar maple decline on the Allegheny Plateau and across northeastern North America has heightened our attention to the distribution of nutrients across the landscape and its relation to glaciation, landscape position, and atmospheric deposition. It has also increased our appreciation of the differences in nutrient requirements among plant species, and how these nutrient requirements can increase or decrease the resilience of forests to stressors such as defoliation and drought. We plan to strengthen our understanding of the relationships among nutrients, landscapes, glacial history, Allegheny Plateau plant species, and forest health, and to develop guidelines to assist managers in integrating this understanding into management strategies. This work will continue to focus primarily on sugar maple, and include development of both maps and indicator plant associations to aid managers in sustaining Northern Hardwood forests. As resources permit, we will add other species to this work.