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The use of witness trees as pyro-indicators for mapping past fire conditions

Formally Refereed
Authors: Melissa A. Thomas-Van Gundy, Gregory J. Nowacki
Year: 2013
Type: Scientific Journal
Station: Northern Research Station
Source: Forest Ecology and Management. 304: 333-344.


Understanding and mapping presettlement fire regimes is vitally important for ecosystem restoration, helping ensure the proper placement of fire back into ecosystems that formerly burned. Witness trees can support this endeavor by serving as pyro-indicators of the past. We mapped fire-adapted traits across a landscape by categorizing trees into two classes, pyrophiles and pyrophobes, and applying this classification to a geospatial layer of witness-tree points centered on the Monongahela National Forest, West Virginia. A pyrophilic percentage was calculated for each point and spatially extrapolated via ordinary kriging to form a continuous geospatial cover. Regression analyses showed pyrophilic percentage was significantly related to a number of key environmental factors and changed along an elevation gradient from low, dry valleys (high pyrophilic percentage) to high, wet mountaintops (low pyrophilic percentage). This approach represents a significant advancement through the direct use of witness trees to depict past fire regimes applicable to both Public Land Survey and metes-and-bounds records.


Biogeography, Metes-and-bounds surveys, Kriging, Historic fire regimes, West Virginia


Thomas-Van Gundy, Melissa A.; Nowacki, Gregory J. 2013. The use of witness trees as pyro-indicators for mapping past fire conditions. Forest Ecology and Management. 304: 333-344.