Distribution and abundance of snags in the Sagehen Creek Basin, California

Abstract

The distribution of snags by tree species in the eastern Sierra Nevada of California generally reflects the associated timber type. Where present, however, lodgepole pine (Pinus contorta Dougl.) forms a large proportion of the snags present. Few snags of any species were present in the Jeffrey pine (P. jeffreyi Grev. & Balf. in A. Murr.) timber type in a study at Sagehen Creek Basin, in Nevada County. Simple regression analysis showed weak but significant relationships betweensnag density and canopy height, canopy cover, and slope. Multiple regression analysis were also weak, but revealed that snag density increased as size of natural openings increased. These results indicate that most snags in the study area were formed by the action of water (i.e.,meadows, creeks) and fire. Thus, managers could concentrate snag surveys (and protective measures) near water and natural openings. Managementof riparian areas is especially important because such areas are usually readily accessible to the public (e.g., fuelwood cutters). Aerial photography should be useful in locating areas of highest snag density; regression analysis appears to be of marginal usefulness.

Citation

Morrison, Michael L.; Dedon, Mark F.; Yoder-Williams, Michael P.; Raphael, Martin G. 1986. Distribution and abundance of snags in the Sagehen Creek Basin, California. Res. Note PSW-RN-389. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Forest and Range Experiment Station. 4 p.