Golden Gardens Park Vegetation Management Plan Prepared for City of Seattle Department of Parks & Recreation 1600 South Dakota Street Seattle, WA 98108 Prepared by Sound Tree Solutions - Duvall, WA Elizabeth Walker Arboriculture and Restoration – Seattle, WA Paul West DECEMBER 2003 EXECUTIVE SUMMARY...............................................................................................1 CHAPTER 1 - OVERVIEW.............................................................................................2 1.1 Introduction .............................................................................................2 1.2 Site Location and Context ......................................................................2 CHAPTER 2 – GOALS, OBJECTIVES AND POLICIES RELATING TO VEGETATION AT GOLDEN GARDENS..............................................3 2.1 Overall Goals...........................................................................................3 2.1.1 Seattle Parks COMP Plan (2000) 2.1.2 Urban and Wildlife Management Plan & Update (2000) 2.1.3 Seattle Parks Tree Policy (2001) 2.1.4 Department Best Management Practices (BMPs) (2002) 2.2 Golden Gardens Park Related Plans .....................................................6 2.2.1 Planting Plan for Golden Gardens Wetland (2001) 2.2.2 North Salmon Bay Community Forestry Strategic Plan (1997) 2.3 Golden Gardens Vegetation Management Plan Goals and Objectives 6 CHAPTER 3 – PLAN CONTEXT...................................................................................8 3.1 Site Character .........................................................................................8 3.2 Park History.............................................................................................8 3.3 Citizen Activities and Concerns .............................................................9 3.4 Interested Organizations ......................................................................10 3.5 Vegetation-related Uses........................................................................11 CHAPTER 4 – ASSESSMENT OF EXISTING CONDITIONS ................................12 4.1 Geology and Soils...................................................................................12 4.2 Slope Stability and Erosion ..................................................................13 4.3 Streams and Wetlands ..........................................................................15 4.4 Forest Character and Condition – Qualitative Description ..............15 4.4.1 Forest Greenspace 4.4.2 Hazard Trees 4.5 Wildlife Habitat.....................................................................................18 4.6 Human Impacts.....................................................................................18 CHAPTER 5 – FINDINGS & DESCRIPTION OF MANAGEMENT AREAS........20 5.1 Geographic Division of Park Areas .....................................................20 5.1.1 Beach 5.1.2 South 5.1.3 Central 5.1.4 North Central 5.1.5 North End 5.1.6 Upper Hillside 5.2 Data Collection Methods.......................................................................22 5.2.1 Forested Hillside Golden Gardens Vegetation Management Plan Sound Tree Solutions Page i December 2003 5.2.2 Hazard Trees 5.3 Findings – General Forest Conditions.................................................24 5.3.1 Overstory 5.3.2 Understory 5.3.3 Decaying Wood Features 5.3.4 Tree Regeneration 5.4 Classification of Management Areas and Overlays............................27 5.4.1 Maple Management Area 5.4.2 Erosion Control Management Area 5.4.3 Conifer Management Area 5.4.4 Re-sprouted Maple Management Area 5.4.5 Wetland Management Area 5.4.6 Border Management Area 5.4.7 Invasive Management Overlay 5.4.8 Gap Management Overlay 5.4.9 Bare Soil Management Overlay 5.4.10 Quality Habitat Management Overlay 5.4.11 Edge Management Overlay 5.5 Hazard Tree Assessment Areas............................................................31 5.5.1 Beach Area 5.5.2 South: Wetland Area 5.5.3 South and Central: Middle Golden Gardens Avenue/Parking Lot Area 5.5.4 Central: Upper Meadow/Main Stair Area 5.5.5 Central: Upper Hillside Conifer Area 5.5.6 North Central: Upper Golden Gardens Avenue Area 5.5.7 North End: Trail Area CHAPTER 6 – VEGETATION MANAGEMENT RECOMMENDATIONS...........33 6.1 Vegetation Management Overview......................................................33 6.1.1 Management Objectives 6.1.2 Adaptive Management Approach 6.1.3 Project Prioritization 6.2 Long-term Targets for Each Management Area................................36 6.3 Prescriptions by Management Area and Overlay ..............................37 6.3.1 Maple Management Area 6.3.2 Erosion Control Management Area 6.3.3 Conifer Management Area 6.3.4 Re-sprouted Maple Management Area 6.3.5 Wetland Management Area 6.3.6 Border Management Area 6.3.7 Invasive Management Overlay 6.3.8 Gap Management Overlay 6.3.9 Bare Soil Management Overlay 6.3.10 Quality Habitat Management Overlay 6.3.11 Edge Management Overlay 6.4 Other Management Prescriptions........................................................43 6.4.1 Vegetation Work on Slopes 6.4.2 Hazard Tree Management 6.5 Other Park Management Issues...........................................................46 6.5.1 View Obstruction with Trees Golden Gardens Vegetation Management Plan Sound Tree Solutions Page ii December 2003 6.5.2 Off-Trail Damage to Slope and Vegetation 6.5.3 Railroad Corridor Safety 6.5.4 Encampments/Party Sites 6.5.5 Noise from Park Users 6.5.6 Dumping 6.5.7 Mountain Beaver Activity 6.5.8 Adjacent Private Property Management CHAPTER 7 – VEGETATION MANAGEMENT & MAINTENANCE PRACTICES ...........................................................................................................................................49 7.1 Project Planning ....................................................................................49 7.2 Managing Laminated Root Rot............................................................49 7.2.1 Symptoms 7.2.2 Signs 7.3 Amending Soils ......................................................................................51 7.4 Creating Snags and Down Woody Debris...........................................52 7.5 Planting ..................................................................................................53 7.5.1 Trees 7.5.2 Shrubs 7.5.3 Live Stakes 7.6 Mulching ................................................................................................55 7.6.1 Trees 7.6.2 Shrubs 7.7 Watering.................................................................................................56 7.8 Three Year Care and Establishment ...................................................57 7.9 Pruning and Removal ..........................................................................59 7.10 Weed and Invasive Control ..................................................................59 7.10.1 Tree Species 7.10.2 Shrub and Vine Species 7.10.3 Herbaceous Species 7.10.4 Listed Noxious Weeds 7.11 Hazard Tree Management Practices ...................................................67 7.11.1 Removal 7.11.2 Inspection 7.11.3 Pruning 7.11.4 Monitoring CHAPTER 8 – PLAN IMPLEMENTATION...............................................................69 8.1 Implementation Priorities.....................................................................69 8.2 Implementation Strategies....................................................................70 8.2.1 Community Partners 8.3 Budget Estimate.....................................................................................70 CHAPTER 9 – MONITORING.....................................................................................75 Golden Gardens Vegetation Management Plan Sound Tree Solutions Page iii December 2003 APPENDICES Appendix A- Field Forms..................................................................................................77 A-1: Vegetation Plot Data Sheet .........................................................................77 A-2: Hazard Tree Assessment Sheet ....................................................................82 Appendix B- Recorded Slides in the Golden Gardens Vicinity ........................................83 Appendix C- Existing Plant Species in Golden Gardens Park ..........................................84 Appendix D- Suggested Plant Communities for Re-vegetation and Enhancement Projects in Golden Gardens ......................................................................86 Appendix E- Restoration Plant List for Golden Gardens Park..........................................91 Appendix F- Vegetation Project Planning Forms..............................................................93 Appendix G- Monitoring Forms........................................................................................96 Appendix H- Public Involvement & Citizen Comment ....................................................98 Appendix I- Bibliography ...............................................................................................103 Appendix J – Vegetation Maps .......................................................................................106 J-1: Existing Conditions ................................................................................................107 J-2: Soils map ..................................................................................................................108 J-3: Habitats on Seattle Public Lands (SUNP) for Golden Gardens & Vicinity ............109