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Table of Contents Introduction ................................................................................................................................. 1 Silvicultural Overview ................................................................................................................ 1 Need for action ........................................................................................................................ 1 Project objectives..................................................................................................................... 2 Regulatory Framework ............................................................................................................ 2 Effects Analysis Methodology ........................................................................................................ 4 Background ............................................................................................................................. 4 Specific Assumptions .............................................................................................................. 7 Affected Environment/Environmental Consequences ........................................................... 11 Environmental Consequences ....................................................................................................... 17 Alternative 1 - No Action .......................................................................................................... 21 Direct and Indirect Effects ..................................................................................................... 21 Cumulative Effects ................................................................................................................ 24 Alternative 2 - Proposed Action ................................................................................................ 24 Product Removal ................................................................................................................... 28 Design Features ..................................................................................................................... 28 Direct and Indirect Effects ..................................................................................................... 30 Cumulative Effects ................................................................................................................ 32 Alternative 3 – Non-commercial alternative ............................................................................. 32 Direct and Indirect Effects ..................................................................................................... 33 Cumulative Effects ................................................................................................................ 36 Comparison of Alternatives ........................................................................................................... 36 Comparison of Alternatives-Simulated Wildfire under 97th Percentile Conditions ................. 41 Summary ....................................................................................................................................... 42 References ..................................................................................................................................... 43 Appendix A -Forest pests and diseases of concern ....................................................................... 46 Appendix B- Metrics for Density Measurement of Tree Vegetation ............................................ 51 Appendix C-Sequoia National Forest Hazard Tree Guidelines ..................................................... 53 Appendix D - Sugar Pine Management ......................................................................................... 54 i Glossary (Terms, Abbreviations and Acronyms) Basal Area (BA) – See Appendix B, this document for explanation; the cross-sectional area of all stems in a stand measured at breast height (4.5 feet) and expressed per unit of land area, generally square feet per acre. California Wildlife Habitat Relationship (CWHR) – A vegetative classification system developed in California to classify wildlife habitats and vegetative structures. Clearcut (clearcutting) – removal of the entire stand in one cutting with reproduction obtained artificially or from seeds germinating after the clearing operation. Common Stand Exams (CSE) – Inventory plots installed to collect stand data and information Diameter @ Breast Height (DBH) – height at which tree diameter is normally measured specified as 4.5 feet above ground base of the tree. Fuelwood – material collected Individual tree selection (free thinning) – removal of individual trees based on project objectives. Pounds per Square Inch (PSI): The number of pounds of ground pressure exerted over one square inch of soil; a metric to assess soil compaction and to define equipment limits. Quadratic Mean Diameter (QMD): The square root of the arithmetic average of the squared values across a particular inventory (Avery and Burkhart 2002). Shade-tolerance – Species that have a tolerance to shading by other species. Shade tolerant species will grow and regenerate under a stand’s over-story. Stand density index (SDI): See Appendix B, this document for explanation; a metric for measuring forested stand density. For this document, averages are reported within the treatment units, where stand examination inventories have been conducted. This is an FVS modeled average for this document. Stocking – an indication of growing space occupancy relative to a pre-established standard, such as basal area or trees per acre. Trees per acre (TPA): The number of trees, on average, on an acre of land where stand examination inventories have been conducted; this is a modeled average for this document. Weighted average: for this document, the forest metric of interest (QMD, TPA, SDI, etc.) multiplied by the sum FVS output times the number of acres divided by the total acres affected. Uneven-aged: Forest stand composed of intermingling of trees that differ markedly in age (Avery and Burkhart 2002) Upper Diameter Limit (UDL) – the diameter at which removal of trees is restricted or meets the objectives of the silvicultural prescription. This may be a hard value or a flexible estimate depending on the type of thinning and the objectives of the silvicultural prescription. i Introduction This report summarizes the potential effects on forest vegetation resources from silvicultural activities proposed for the Rancheria Forest Restoration Project of the Kern River Ranger District of the Sequoia National Forest. This assessment addresses how the different alternatives impact the forest vegetation within the project area proposed by the Rancheria EA document. The report also addresses the scientific and analytical basis for the comparison of alternatives as presented in this report. This specialist report is being prepared for the Rancheria Forest Restoration Environmental Analysis (EA). Silvicultural Overview This assessment addresses how the different alternatives impact forest vegetation, as measured by stand density (basal area or stand density index, and indirectly crown canopy cover), stand composition (trees per acre by species), and stand structure (trees per acre by diameter class, ). These measurements are correlated to appropriate stocking levels, and stand conditions to maintain stand growth and health, including resistance to epidemic levels of insects and disease. This report addresses current and desired stand conditions and the silvicultural treatment options. The Rancheria Project proposes to treat vegetation to achieve several goals and objectives, which includes improving forest health by treating vegetation for insect and disease. Silvicultural treatments will reduce tree density, alter stand composition and stand structure creating conditions which will control insect populations, maintain them at endemic levels and improve the growth of trees, forest stands, and the vegetation across the landscape. Tree and forest health conditions also contribute significantly to the fire risk; therefore silvicultural treatments that improve forest health and lower risk of insect and disease outbreaks, would contribute to altering fire risk and behavior. For example, in certain stand structure conditions, the amount of vegetation mortality from insect/disease conditions, can increase both crown fire potential and contribute to increased fuel levels now and over time. Thinning forest stands to specific standards contributes to maintaining forest health while achieving fire behavior objectives. Mechanical thinning operations have the ability to effectively (both economically and ecologically) remove trees of varying sizes while managing the reduction of canopy cover, and residual fuel levels. Need for action Vegetation conditions in the project area are departed from historic norms, and are at or beyond the range of natural variability. Large ponderosa pine (Pinus ponderosa), Jeffrey pine (P. jefferyii), and California black oak (Quercus kelloggii) were logged from the Greenhorn Mountains around the mid-1800’s, in concert with the development of local mining, agriculture, tourism, ranching and town of Bakersfield. The result of a 100 year policy of fire suppression combined with historic logging is a dense second-growth forest with trees that are smaller, more uniform, and of different relative species composition than were historically present, leaving