Dr. Barry R. Flamm, Dr. David S. Wilcove, Karin P. Sheldon, Jean C. Durning, Melanie J. Rowland, and H. Michael Anderson of The Society's staff reviewed and commented on draft manuscripts. Staff in The Society's Washington State, Oregon, and California regional offices provided useful information for the study.
We are grateful for the many volunteers who assisted with computer software and hardware operations, digitizing, map preparation, and field verification. Among them are Jeff Ladd, Dave Lilly, Beatrice Booth, Sue Clark, Ron Nims, Joel Stocker, Jack Wheeler, Nathan Shumaker, Ciel Sanders, Linda Wilkinson, Don Dewitt, J. P. Roseland, Angela Miller, David Werntz, Tom Schrieber, and Rick Vanslow. We end with a special note of thanks to Dr. Roger Morrison for his support of this project and to Michael J. Wilburn who provided funding for an AST Premium 386/33 computer and tape drive system in memory of Joe and Nell Wilburn and Donna, Meagan and Mark McDonald.
It is not possible to determine all important old-growth characteristics from aerial photographs or satellite images. Even existing field plots often do not provide adequate information about log and snag densities in old-growth stands.Therefore, forest stands were mapped as old growth when analysis of surrounding plot data and of canopy characteristics observable on aerial photographs indicated the stands exhibited most of the ecological characteristics of old-growth forests. As a result, old growth shown on the map may not meet all of the criteria in the Forest Service and Bureau of Land Management Old-Growth Task Group's definition for old growth. And, some borderline old-growth stands may be included in the "other ancient forest" category. The spectral characteristics on satellite images for some areas of younger and older forests can be similar. Due to this limitation, some error in classification of these forests exists.