Background

Through the Inter-Tribal Timber Council’s “Anchor Forests” project, we have partnered with The Nature Conservancy in Washington (TNC) to evaluate forest restoration needs and possible woody supply from forest restoration treatments across eastern Washington. These analyses are built largely upon two prior studies, the Washington Forest Biomass Assessment and the TNC-USFS R6 Joint Analysis of Forest Restoration Needs.

The TNC-USFS R6 Joint Analysis of Forest Restoration Needs evaluated where, how much, and what types of “transitions” are currently needed to restore a Natural Range of Variability (NRV) in forest structure across eastern Washington. This study builds off the conceptual framework of the LANDFIRE and Fire Regime Condition Class (FRCC) programs and is based on four primary data inputs: 1) a classification and map of forested biophysical settings (ILAP3), 2) NRV reference conditions for each biophysical setting (Landfire4), 3) a delineation of “landscape units” for each biophysical setting, and 4) a map of present day forest vegetation structure based on Oregon State University Gradient Nearest Neighbor analysis.

Our Work

Using the parcel, forestland, and simulation database developed for the Washington Biomass Supply study, we first analyzed the departure in current structure classes by biophysical setting from NRV for the North Central Cascade, South Central Cascade, and Northeast landscape units.  TNC defined transitions between structure classes as "disturbance only", "succession only', or "disturbance then succession."  These transitions were modeled from 2005 to 2035 using forest growth and treatment simulations with the Forest Vegetation Simulator.

Three harvest level scenarios were developed for eastern Washington.  The "Baseline" scenario represented a continuation of current harvest levels.  A "Forest Service Aggressive" scenario was developed to analyze the impact increased forest health treatments on Forest Service land would have on restoration needs.  The "Hybrid" scenario...

The spatially explicit nature of the Washington Biomass Supply Assessment database allowed scenarios to be implemented realistically, with treatments constrained by slope, riparian and wetland buffers, and distance from existing roads, depending on owner and treatment type.

Results

Deliverables