Landscape Conservation Forecasting Report to the Powell Ranger District, Dixie National Forest, USDA Forest Service September 2010 Western margin of the Paunsaugunt Plateau, © Joel S. Tuhy, 1998. By Joel Tuhy, Louis Provencher, and Greg Low The Nature Conservancy Moab, Utah and Reno, Nevada Table of Contents Page Executive Summary ................................................................................................. 1 Introduction.............................................................................................................................. 1 Process and Methods ............................................................................................................... 1 Key Findings ............................................................................................................................ 4 Introduction .............................................................................................................. 6 Background .............................................................................................................................. 6 Project Area ............................................................................................................................. 7 Objectives ................................................................................................................................. 9 Process and Methods .............................................................................................. 10 Vegetation Mapping ............................................................................................................... 11 Mapping Biophysical Settings and S-Classes .................................................................. 11 Biophysical Setting Descriptions and Natural Range of Variability (NRV) ................... 13 Assessment of Current Ecological Condition – Calculating Ecological Departure ............. 14 Refinement of Predictive Ecological Models ......................................................................... 15 Core Reference Models and Descriptions........................................................................ 16 Management Models ........................................................................................................ 16 High-Risk Vegetation Classes ......................................................................................... 17 Accounting for Variability in Disturbances and Climate ................................................ 17 Fire Activity ............................................................................................................... 18 Upland Variability ..................................................................................................... 18 Riparian Variability ................................................................................................... 19 Assessment of Future Ecological Condition – Minimum Management ................................. 22 Assessment of Future Ecological Condition – Alternative Management Strategies ............. 23 Objectives ........................................................................................................................ 24 Management Strategies .................................................................................................... 24 Management Scenarios .................................................................................................... 25 Computer Simulations and Reporting Variables ............................................................. 25 Return On Investment (ROI) Analysis.................................................................................... 26 Findings .................................................................................................................. 28 Current Ecological Condition................................................................................................ 28 Ecological Departure ....................................................................................................... 28 High-Risk Vegetation Classes ......................................................................................... 30 Predicted Future Ecological Condition – Minimum Management ........................................ 32 Ecological Departure ....................................................................................................... 32 High-Risk Vegetation Classes ......................................................................................... 33 Prioritizing Actions for Implementation: Return-on-Investment ........................................... 33 Management Strategies and Scenarios .................................................................. 37 Introduction............................................................................................................................ 37 Ponderosa Pine Ecological System ....................................................................................... 38 i Management Objectives................................................................................................... 38 Management Strategies and Costs ................................................................................... 39 Outcomes ......................................................................................................................... 39 Aspen–Spruce-Fir Ecological System .................................................................................... 40 Management Objectives................................................................................................... 40 Management Strategies and Costs ................................................................................... 41 Outcomes ......................................................................................................................... 41 Aspen–Mixed Conifer Ecological System .............................................................................. 42 Management Objectives................................................................................................... 42 Management Strategies and Costs ................................................................................... 43 Outcomes ......................................................................................................................... 43 Mixed Conifer Ecological System .......................................................................................... 44 Management Objectives................................................................................................... 44 Management Strategies and Costs ................................................................................... 44 Outcomes ......................................................................................................................... 45 Black/Low Sagebrush Ecological System .............................................................................. 46 Management Objectives................................................................................................... 46 Management Strategies and Costs ................................................................................... 46 Outcomes ......................................................................................................................... 47 Wyoming/Basin Big Sagebrush Ecological System ............................................................... 48 Management Objectives................................................................................................... 48 Management Strategies and Costs ................................................................................... 49 Outcomes ......................................................................................................................... 49 Montane Sagebrush Steppe Ecological System ..................................................................... 50 Management Objectives................................................................................................... 50 Management Strategies and Costs ................................................................................... 50 Outcomes ......................................................................................................................... 51 Montane-Subalpine Riparian Ecological System .................................................................. 52 Management Objectives................................................................................................... 52 Management Strategies and Costs ................................................................................... 53 Outcomes ......................................................................................................................... 53 Gambel Oak–Mixed Mountain Brush Ecological System ...................................................... 54 Management Objectives................................................................................................... 54 Management Strategies and Costs ................................................................................... 54 Outcomes ......................................................................................................................... 55 Summary of Management Scenarios ...................................................................................... 56 Conclusions ...........................................................................................................