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Zybach, Bob 1996. Historical Overview of Columbia Gorge Forestlands: Dynamics and Fragmentation, 1792-1996. NW Maps Co., Corvallis, OR: 67 pp. [PDF: (black and white only) 7.1 mb.]. Color maps [PDF: 3.8 mb.].

This report considers 200-years of forest fragmentation history as it pertains to northern spotted owl habitat in the area of the Columbia River Gorge, as defined by US Fish and Wildlife Service (USFWS 1995) and the Washington Forest Practices Board (WFPB 1996).


Any attempt to reduce forest fragmentation in the study area through the creation of contiguous older forest types will likely increase the potential for catastrophic forest fires. This is caused by increasing fuel loads and by linking areas of concentrated habitat with bands of flammable snags, litter, canopies and volatile ladder fuels. In other words, attempts to create larger stands of older tress than have existed during earlier times will probably result in greater risk to these stands throughout history (Zybach 1996: 65).