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July 2013

Restoration is a major focus area for the USDA Forest Service in managing its 193 million acres of forests and grasslands and in influencing management on hundreds of millions of acres of private and urban lands.  Restoration efforts seek to help repair ecosystems that have been damaged or degraded by factors such as invasive plants and insects, disease, extreme weather, fire exclusion and over exploitation.

Featured Scientist

Paul Schaberg

Dr. Paul Schaberg

Paul Schaberg is a Research Plant Physiologist with the Northern Research Station and his research is all about stress; specifically the impacts of stress from human activities and extreme weather events on tree health. 

Schaberg is currently the coordinator of a diverse group of scientists from the USDA Forest Service (Northern, Southern and Pacific Northwest Research Stations), the University of Vermont and other institutions that evaluate the influence of various stressors on the ability of trees to survive and thrive.  Trees experience stress in the face of factors such as air pollution, water pollution, climate change, and associated extreme weather.  These stresses affect a tree’s tolerance of cold, the ability to take up nutrients from soil, and leaf pigmentation (fall colors).  

A recently published report by Schaberg and his collaborators documented the long-term impacts from a severe winter injury (freeze-induced foliar mortality) event that hit the northeastern U.S. in 2003 and damaged more than 90% of the red spruce trees in the region.  The researchers began assessing damage on trees in Vermont, New Hampshire and Massachusetts shortly after the storm and continued to monitor tree health over the next 10 years.  Results of the study indicated growth declines in the red spruce trees, especially in the higher elevations, that lasted 7 years.  Surprisingly, more recently, the red spruce trees injured in 2003 are now experiencing a growth surge. Yearly growth is now the highest it has ever been and trees are growing at nearly 2 times the average for the last 100 years.  New research is examining the cause(s) of this recent growth surge. 

By understanding how trees respond to environmental stress we can take actions to prevent decline or loss of forest tree species and help ensure the continued delivery of ecosystem services trees provide.


Find out more on Paul Schaberg's scientist profile

Featured Product

Foresters tally seedlings during an inventory of an oak stand.

SILVAH, short for Silviculture of Allegheny Hardwoods, is a decision support software tool developed in the 1970’s by Northern Research Station scientists.  Originally developed for managers of Allegheny Hardwood forests, SILVAH was expanded with the help of the Pennsylvania Bureau of Forestry to address mixed oak forests in 2002.

The SILVAH computer program takes site-specific inventory data and management objectives provided by the user and through its science-based “expert system” provides a silvicultural prescription, or “how to”, that enables managers to move their forest stands toward the desired condition. SILVAH has a particular emphasis on promoting adequate regeneration for sustaining forests.  This knowledge transfer is critical to sustaining Allegheny Hardwood and mixed oak forests and the benefits they provide in the upper Appalachian region. 

The SILVAH computer program is just one part of a much larger SILVAH approach, which includes intensive week-long training sessions for managers of Northern Hardwood and mixed oak forests. Both the training sessions and software are continually updated to incorporate the latest research on sustaining forests.  Since initial development, the NRS has provided training on software use to more than 2,500 land managers from at least 19 states and 4 countries. 

More information on SILVAH 6.2  
More information on the SILVAH partnership

Featured Research

Understory red spruce in a forest with northern hardwoods in the overstory.

Red spruce was once a dominant species in the cool, moist, high elevations of West Virginia.  However, exploitative logging in the early 1900s along with subsequent fires has decreased red spruce presence significantly.  A range of efforts, including recent research by Northern Research Station scientists and their collaborators, has focused on restoring the high elevation red spruce forests that had been largely ignored by forest research and management efforts for decades. 

Northern Research Station scientists identified specific site characteristics historically associated with the presence of red spruce to help define restoration goals and identify potential restoration sites.  This information will increase the likelihood of success by land managers in their restoration efforts.  Making this research particularly important is the fact that the recently de-listed federally endangered Virginia northern flying squirrel is endemic to these high elevation spruce forests.   

In addition to recent research efforts on restoration of high elevation red spruce, the NRS is a founding member of the Central Appalachians Spruce Restoration Initiative (CASRI) and was a leader in organizing the 2009 Conference on the Ecology and Management of High-Elevation Forests in the Central and Southern Appalachians.

Featured Partnership

Research scientists and industry cooperators discuss management options for northern white-cedar in Maine.

Known familiarly as the “Cedar Club” a group of researchers from the Northern Research Station (NRS), the University of Maine, Laval University (Quebec), the Canadian Forest Service and the Quebec Ministry of Natural Resources have been working together for more than 10 years to learn more about the ecology and silviculture of northern white-cedar. 

Northern white-cedar is a common tree species throughout the Northeast, the Lake States and nearby Canada.  The species is significant from both an ecologic and economic perspective, however prior to this research partnership it had been one of the least studied commercially valuable tree species in its range.  With concerns about the long-term viability of northern white-cedar due to problems with cedar regeneration, the research team sought to fill this knowledge gap, through a collaborative and targeted research effort.  

In 2012 the NRS published the “Silvicultural guide for northern white-cedar (eastern white cedar)” as a General Technical Report (GTR NRS-98).  The guide presents a compilation of the knowledge gained through the research partnership effort.  The volume includes a description of the cedar resource in the northeastern United States, Quebec and Ontario, Canada, silvics of cedar and common associates, and recommendations for managing and regenerating cedar in pure and mixed-species stands.  This information will play a critical role in effective forest management and long-term sustainability of the northern white-cedar resource.