Enhancement of Degraded Shrub-Steppe Habitats with an Emphasis on Potential Applicability in Eastern Washington Technical Note 443 December 2013 Suggested citation: Dunwiddie, P., and P. Camp. 2013. Enhancement of Degraded Shrub-Steppe Habitat with an Emphasis on Potential Applicability in Eastern Washington. Tech Note 443. Bureau of Land Management, Spokane District, Spokane, WA. Production services provided by: Bureau of Land Management National Operations Center Information and Publishing Services Section P.O. Box 25047 Denver, CO 80225 BLM/OC/ST-14/001+6711 Cover photo: A diverse Wyoming big sagebrush/bluebunch wheatgrass steppe site above Moses Coulee in Grant County, Washington. (Photo by Peter Dunwiddie) Enhancement of Degraded Shrub-Steppe Habitats with an Emphasis on Potential Applicability in Eastern Washington Authors: Peter Dunwiddie, Affiliate Professor, School of Environmental and Forest Sciences, University of Washington Pam Camp, Ecological Consultant and former Bureau of Land Management Botanist Technical Note 443 December 2013 Photo by K. Rupp Acknowledgments A number of people generously provided their experiences and expertise for the preparation of this technical note. Katrina Strathmann (Yakama Nation), Dan Peterson (Washington Department of Fish and Wildlife), Courtney Smith (Natural Resources Conservation Service), Chuck Warner and David St. George (The Nature Conservancy), and Mel Asher (BFI Native Seeds) all enriched this technical note by sharing their restoration project experiences. Chris Sheridan and Molly Boyter (Bureau of Land Management) helped shape and improve the scope and content by providing input, guidance, and comments. Financial support for the preparation of this tech note was provided by the Bureau of Land Management. Enhancement of Degraded Shrub-Steppe Habitats with an Emphasis on Potential Applicability in Eastern Washington Technical Note 443 iii Photo by Matt Lavin Table of Contents Abstract ........................................................................................................................................ 1 1. Introduction ............................................................................................................................ 3 1.1 Emphasis and Focus of Technical Note ........................................................................ 3 1.2 Restoration of Extant vs. Potential Shrub-Steppe ......................................................... 4 2. Methods and Sources ............................................................................................................... 7 2.1 Consulting Practitioners .............................................................................................. 7 2.2 Case Studies ................................................................................................................. 7 2.3 Literature Mining ........................................................................................................ 8 3. Physical and Biological Characteristics of Shrub-Steppe ..................................................... 11 3.1 Climate...................................................................................................................... 11 3.2 Topography and Geology ........................................................................................... 12 3.3 Soils ........................................................................................................................... 12 3.4 Vegetation .................................................................................................................. 12 3.5 Ecological Dynamics ................................................................................................. 14 3.6 Sage-Grouse Habitat Requirements ........................................................................... 15 4. General Approaches to Shrub-Steppe Restoration ............................................................... 17 5. A Restoration State-and-Transition Model for Shrub-Steppe .............................................. 23 5.1 Restoration State-and-Transition Model Description ................................................. 24 5.2 Catalogue of State-and-Transition Model Starting States ........................................... 25 5.3 Catalogue of State-and-Transition Model Restored States .......................................... 26 5.4 Catalogue of Transitions ............................................................................................ 27 6. Restoration of Degraded Shrub-Steppe ................................................................................ 31 6.1 Setting Restoration Goals .......................................................................................... 31 6.2 Assessing Site Conditions and Reference Sites ............................................................ 31 6.3 Defining Explicit Restoration bjectivesO ................................................................... 35 6.3.1 Setting Species Composition and Abundance Objectives ............................. 36 6.3.2 Setting Species Distribution Objectives ....................................................... 36 6.3.3 Setting Vegetation Structure Objectives ....................................................... 37 Enhancement of Degraded Shrub-Steppe Habitats with an Emphasis on Potential Applicability in Eastern Washington Technical Note 443 v 6.4 Identifying Needed Interventions ..................................................................................................... 37 6.5 Assessing Project Feasibility .............................................................................................................. 40 6.6 Decision Tree for Shrub-Steppe Restoration ..................................................................................... 41 6.7 Identifying Restoration Treatments ................................................................................................... 44 6.7.1 Restoration Principles ......................................................................................................... 46 6.7.2 Reducing Shrub Abundance in Overly Dense Stands .......................................................... 49 6.7.3 Controlling Invasive Weeds ................................................................................................ 50 6.7.4 Increasing Native Species Where Shrubs are Absent ............................................................ 53 6.7.5 Increasing Grasses and Forbs Where Shrubs are Present ...................................................... 58 6.7.6 Species Selection ................................................................................................................. 59 6.7.7 Assessing Treatment Costs .................................................................................................. 62 6.7.8 Reconciling Treatments with Transitions ............................................................................ 67 References ......................................................................................................................................................... 69 Appendix 1. List of Practitioners Contacted Regarding Shrub-Steppe Restoration ....................................... 77 Appendix 2. Restoration Project Documentation Form .................................................................................. 79 Appendix 3. Planning Form for Restoring Degraded Shrub-Steppe .............................................................. 83 Table of Figures Figure 1. Average annual precipitation in eastern Washington, 1971-2000 ........................................................ 11 Figure 2. Basic state-and-transition model for Wyoming big sagebrush/bluebunch wheatgrass steppe ................ 14 Figure 3. Example of a sequential approach for restoring shrub-steppe habitats ................................................. 19 Figure 4. State-and-transition model for shrub-steppe in Washington, illustrating key vegetation states of importance to restoration managers ....................................................................................... 23 Figure 5. Hypothesized interactions of site physical characteristics on the likelihood of restoration success ........ 33 Figure 6. Hypothetical, staged restoration of shrub-steppe Starting State 1b (from Figure 4) ............................. 40 Figure 7. Decision tree for enhancing degraded shrub-steppe............................................................................. 43 Enhancement of Degraded Shrub-Steppe Habitats with an Emphasis on Potential Applicability in Eastern Washington Technical Note 443 vi Table of Tables Table 1. Changes in major functional groups associated with transitions from starting states and transitions from restored states ...................................................................................................... 29 Table 2. Site-related factors that may affect restoration outcomes and that should be assessed prior to commencing restoration activities ........................................................................................................ 32 Table 3. List of species, grouped by functional type, from a Natural Resources Conservation Service ecological site description of dry loamy soils in a zone with 9-15 inches of annual precipitation .......................... 39 Table 4. Causes of succession, contributing processes and components, and modifying factors .........................