Stand-Density Study of Spruce-Hemlock Stands in Southeastern Alaska

摘要

The lack of growth and yield information for young even-aged western hemlock (Tsuga heterophylla (Raf.) Sarg.)-Sitka spruce (Picea Sitchensis (Gong.) Carr.) stands in southeastern Alaska served as the impetus for a long-term stand density study begun in 1974. The study has followed permanent growth plots in managed stands under various thinning reigmes. Between 1974 and 1987, 272 plots were established at 59 locations throughout Southeastern Alaska. Remeasurement of the plots occurs every two to four years and will continue until harvest. Additional thinnings will occur on a portion of the plots. Future plans include extending the study through establishment of installations in stand types not currently represented. Once data for an entire rotation are obtained, a comprehensive set of growth and yield tables for various management regimes can be developed. This information will answer questions forest managers have on whether and when to thin a stand, at what level of intensity, and how frequently to enter the stand.