15. Attachment 3 - SERAL_FEIS_2022Feb.pdf

Social and Ecological Resilience Across the Landscape Final Environmental Impact Statement Volume I. Chapters 1 through 6 and Appendices

Forest Service Stanislaus National Forest February 2022

Cover photo: Stanislaus National Forest staff: Photo taken from near Forest Service Road 5N17, looking west into the SERAL project area on 8/27/2020. A layer of smoke from fires burning outside the Stanislaus National Forest can be seen in the background.

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Social and Ecological Resilience Across the Landscape (56500)

Final Environmental Impact Statement Stanislaus National Forest

Lead Agency: USDA FOREST SERVICE

Responsible Official: JASON KUIKEN, FOREST SUPERVISOR Stanislaus National Forest 19777 Greenley Road Sonora, CA 95370

For Information Contact: BENJAMIN COSSEL, PUBLIC AFFAIRS OFFICER Stanislaus National Forest 19777 Greenley Road Sonora, CA 95370 Benjamin.Cossel@usda.gov

Abstract: The final environmental impact statement (FEIS) identifies the Responsible Official’s preferred alternative (Alternative 1) and two additional action alternatives to (Alternatives 3 and 4) designed to reduce wildfire risk and to improve forest health and resilience. The actions proposed include forest thinning, fuel reduction, prescribed fire, limited salvage, fuelbreaks, and non-native invasive weed control. The FEIS also presents a focused analysis addressing the potential direct, indirect, and cumulative environmental effects related to issues that may occur from the proposed actions as well as the effectiveness of the proposed treatments.

Submit Objections Online: https://www.fs.usda.gov/project/?project=56500 Under “Get Connected” – “Comment / Object on Project” link.

Mail Objections to: JENNIFER EBERLIEN, REGIONAL FORESTER USFS Region 5

ATTN: SERAL

1323 Club Drive Vallejo, CA 94592

Opportunity to Object: The 45-day Opportunity to Object starts after the Notice of Availability (NOA) of the FEIS is published in the Federal Register and newspaper of record the Union Democrat.

Objector’s Note: Individuals or entities who submitted timely, specific written comments during a designated opportunity for public comment are eligible to file an objection1. Objections must be based on previously submitted timely, specific written comments unless based on new information arising after the designated comment opportunities. Objections must include the following information2: (1) Objector’s name and address, with telephone number, if available; (2) Objector’s signature or other verification of authorship; (3) identification of a single lead objector when applicable; (4) project name, Responsible Official name and title, and name of affected National Forest; (5) description of the aspects of the project being objected to, including specific issues related to the proposed project; (6) specific reasons for, and suggested remedies to resolve, the objection; and (7) description of the connection between the objection and the objector’s prior comments, unless the objection concerns an issue that arose after the designated opportunities to comment.

1 (36 CFR 218.5(a)) 2 (36 CFR 218.8(d)) mailto:kathryn.wilkinson@usda.gov https://www.fs.usda.gov/project/?project=56500

Table of Contents Summary

1. Purpose of and Need for Action

1.01 Increase Landscape Resilience to Natural Disturbances (drought, insects, disease, wildfire) by Restoring Resilient Forest Conditions as Guided by the Natural Range of Variation

1.02 Provide Economic Opportunities to Local Communities

1.03 Maintain Safe Access to Public Lands

1.04 Reduce the Spread of Invasive Non-Native Weeds

2. The Alternatives Alternatives Considered in Detail

Comparison of Alternatives

Management Requirements

Alternatives Considered but Eliminated from Detailed Study

3. The Environmental Consequences

3.01 Issues Related to the Alternatives

3.02 Ability of the Alternatives to Meet the Purpose and Need

4. List of Preparers

4.01 Interdisciplinary Team

4.02 Additional Technical Advisors and Contributors

4.03 Yosemite Stanislaus Solutions Collaborators

5. List of Agencies, Organizations, and Persons to Whom Copies of the Statement are Sent

5.01 Federal, State and Local Agencies

5.02 California State Agencies

5.03 Local Elected Officials

5.04 Tribes

5.05 Individuals and Organizations

6. Regulatory Review of Other (than NEPA) Law, Regulation, and Policy Compliance

6.01 National Forest Management Act (NFMA) — Land Management Plan Consistency and Compliance

6.02 Endangered Species Act

6.03 Forest Service Sensitive Species (Forest Service Manual 2670)

6.04 Management Indicator Species (Forest Service Manual 2630)

6.05 Invasive Species Management (Forest Service Manual 2900, Executive Order 13112)

6.06 National Historic Preservation Act (NHPA) – Section 106 Review

6.07 Soil Quality and Hydrologic Function (FSM 2500 – USDA 2010)

6.08 Soil Conditions (FSM 2500 Chapter 2550 Supplement – USDA 2012)

6.09 Water Quality Management Handbook (FSH 2509.22, Chapter 10 - USDA 2011)

6.10 National Best Management Practices for Water Quality Management on National Forest System Lands (Vol. 1 – National Core BMP Technical Guide. FS-990a)

6.11 Protection of Wetlands (Executive Order 11990) and Floodplain Management (Executive Order 11988) 132

6.12 Clean Water Act (CWA)

6.13 Migratory Bird (Executive Order 13186)

6.14 National Forest System Land Management Planning Rule (36 CFR 219)

6.15 Clean Air Act (CAA), Air Quality, and Smoke Emissions

6.16 Environmental Justice (Executive Order 12898, as amended by EO 14008)

6.17 Consideration of Climate Change

Appendix A: Additional Tables Appendix B: Project-Specific Forest Plan Amendments

Terminology Used in Proposed Forest Plan Amendments

Proposed Project-Specific Forest Plan Amendments

Appendix C: Literature Cited Appendix D: Glossary Appendix E: Using Landscape Condition Metrics and ForSys Appendix F: California Spotted Owl Pre-Implementation Process

California Spotted Owl Site Remapping and Project Requirements Compliance

Appendix G: Response to Comments

List of Tables Table 1: General vegetation types in the project area Table 2. High risk SDI thresholds (USDA 2021(c)) Table 3: Habitat quality categories for CSO nesting and roosting based on structural characteristics of forests.

Table 4: Acres of California spotted owl habitat at multiple scales Table 5: California spotted owl management objectives and desired conservation outcomes Table 6: Existing understory vegetation and dead fuel loads across the landscape Table 7: Acres of estimated fire return interval departure by condition class (CC) category Table 8. Expected fire type Table 9. Acres of predicted vegetation burn severities Table 10. Acres of conditional flame length categories Table 11. Acres of annual burn probabilities from FSim modeling Table 12. Alternative 1 forest thinning DBH limits Table 13: Desired structure within forested stands based on NRV Table 14. Approximate Stand Density Index (SDI) range by forest type and topographic position under Alternative 1 Table 15. Potential forest thinning modifications when faced with insect-, disease-, or drought-mortality Table 16: Summary of acres of proposed fuelbreak treatments Table 17: Fuelbreak treatment specifications Table 18. Non-native Invasive plants known to occur within the project area Table 19: Alternative 3 DBH limitations Table 20. Alternative 4 DBH limitations Table 21. Comparison of proposed treatments among action Alternatives (Alt. 1, 3, and 4) Table 22. Upper diameter at breast height limits for mechanical treatments Table 23. Issues Table 24. Acres of existing high-quality and best-available CSO habitat Table 25. Issue 1A direct and indirect effects. PAC acres are mutually exclusive in this table Table 26: Issue 1B acres of direct and indirect effects Table 27: Comparison of DBH limits among action alternatives Table 28. SDI threshold categories Table 29. Issue 3A direct and indirect effects (acres, all lands combined) Table 30: Issue 4 direct and indirect effects

Table 31. WSR segments and ORVs potentially affected by the SERAL proposed actions Table 32. Issue 5 direct and indirect effects Table 33. Issue 6A effects – Acres reported for territories include the overlapping PAC acres Table 34. Issue 6B effects Table 35. Issue 6C effects Table 36. Issue 8 direct and indirect effects Table 37. Need 1 effectiveness Table 38. FVS post-treatment results of representative stands found within the SERAL project area Table 39: Miles of access roads on NFS lands within the project area Table 40. Miles of roads on NF lands with Potential Hazard Tree Removal Table 41: Effect Determination for Endangered Species Act species and habitat Table 42. Effect determinations for Forest Service Sensitive Species Table 43: Application of the Directly Related Substantive Requirements

List of Figures Figure 1. Project area vicinity map Figure 2. Current landscape structure of Yellow Pine/Dry Mixed Conifer and Fir/Moist Mixed Conifer forest types compared to historic conditions Figure 3: Schematic displaying the inner-core and outer-core fuelbreak zones Figure 4. Example of a shaded fuelbreak in a conifer forest Figure 5. Example of a fuelbreak in an oak woodland. .................................... Error! Bookmark not defined.

Figure 6. Log decay classes Figure 7. Percentage of conifer forests within the SERAL project area at risk of density-related mortality. .. 73 Figure 8: Acres of conifer forests within the SERAL project area at varying risk levels of density-related mortality Figure 9: Acres of pine-dominant forests in the SERAL project area above and below thresholds associated with density-related mortality Figure 10 Acres of fir-dominant forests in the SERAL project area above and below thresholds associated with density-related mortality Figure 11. A comparison of post-treatment landscape structure of the yellow pine / dry mixed conifer forest types among the alternatives compared to historic conditions Figure 12. A comparison of post-treatment landscape structure of the fir / wet mixed conifer forest types among the alternatives compared to historic conditions

List of Acronyms BA Biological Assessment or Basal Area BMP Best Management Practices Cal-IPC California Invasive Plant Council CC Condition Class CCF Hundred Cubic Feet CDFA California Department of Food and Agriculture CFR Code of Federal Regulations CSO California Spotted Owl CWA Clean Water Act CWE Cumulative Watershed Effects CWHR California Wildlife Habitat Relationship DBH Diameter at Breast Height DEIS Draft Environmental Impact Statement EEC Expected Environmental Concentration EIS Environmental Impact Statement ESA Endangered Species Act ESD Emergency Situation Determination FERC Federal Energy Regulatory Commission FIA Forest Inventory and Analysis FRID Fire Return Interval Departure FSH Forest Service Handbook FSIM the large-fire simulation system FSM Forest Service Manual FVS Forest Vegetation Simulator GIS Geographic Information System GTR General Technical Report HRCA Home Range Core Area HQ Hazard Quotient HUC Hydrologic Unit Code HVRA Highly Valued Resource and Asset LIDAR light detection and ranging LMU Land Management Unit LOP Limited Operating Period MCL Maximum Contaminant Level MDBM Mt. Diablo Base and Meridian MSDS Material Safety Data Sheet NCFS Northern California Fire Severity Prediction System NF National Forest NEPA National Environmental Policy Act NFS National Forest System NOA Notice of Availability NOAEC No observed adverse effect concentration NOEL No-observed-effect-level NRV Natural Range of Variation OHV Off-highway vehicle PAC Protected Activity Center

PIF Project Input Form ORV Outstandingly remarkable values POD Potential Operational Delineations PPE Personal protective equipment QMD Quadratic Mean Diameter RfD Human Reference Dose ROD Record of Decision SDI Stand Density Index S&G Standards and Guidelines SPI Sierra Pacific Industries TOC Threshold of Concern TPA Trees Per Acre USDA United States Department of Agriculture USFS United States Forest Service WHR Wildlife Habitat Relationship WSR Wild and Scenic River WUI Wildland Urban Interface

SUMMARY

The Social and Ecological Resilience Across the Landscape (SERAL) project has been developed to restore forest resilience and the ability of the landscape across the project area to persist with fire as a natural process.

The SERAL project is centrally located on the Stanislaus National Forest, within the Yosemite Stanislaus Solutions collaborative area, with portions located on the Calaveras, Mi-Wok, and Summit Ranger Districts (Figure 1). The SERAL project area is located south and east of the North Fork Stanislaus River and north and west of the North Fork Tuolumne River. The project area is also almost entirely to the north and west of Highway 108 (T2N-T5N, R14E-R18E; MDBM).

Figure 1. Project area vicinity map.

Project Purpose and Need After comparing the exiting and desired conditions of the project area’s landscape and reviewing public feedback received during scoping, the Forest identified and refined the following purpose needs for the project:

• Increase Landscape Resilience to Natural Disturbances (drought, insects, disease, wildfire) by Restoring Resilient Forest Conditions as Guided by the Natural Range of Variation o Increase forest heterogeneity (within- and between stands) o Reduce stand densities o Retain large, old, and structurally diverse trees and snags o Increase the relative abundance of fire-tolerant and shade-intolerant trees o Reduce surface and ladder fuels o Increase management use of fire through larger, watershed scale efforts that mimic the natural range of fire severity and frequency o Construct and maintain a network of fuelbreaks to support prescribed fire and wildfire operations o Salvage drought, insect, disease, and wildfire disturbed areas for NRV-based restoration and conservation benefits

• Provide Economic Opportunities to Local Communities

• Maintain Safe Access to Public Lands

• Reduce the Spread of Invasive Non-Native Weeds.

Concerns Identified by the Public (Issues) Issues were identified from public comments received during scoping and the DEIS comment period.

Issues summarize concerns or perceived issues submitted by the public related to the actions proposed.

These public concerns were molded into cause-effect statements to describe what aspect of the proposed actions or EIS content a concern is related to and the environmental effect(s) or impacts expected to result from that specific action or actions. These cause-effect statements serve to highlight effects or unintended consequences that may occur from the proposed actions and action alternatives and to focus the EIS analysis. The FEIS presents an analysis which directly addresses and resolves each of the perceived issues. Table 23 presents each of the main concerns submitted by the public.

The key concerns or perceived issues submitted by the public were related to DBH limits, potential impacts to CSO habitat, concerns regarding the proposed project-specific forest plan amendments, the use of herbicides, and the potential impacts to wild and scenic river characteristics.

Response to DEIS Comments During the 45-day opportunity to comment on the DEIS, 23 unique individual letters and 38 form+ letters were submitted from private individuals, organizations, groups, agencies, and industry professionals (Table G.X). Letters included comments expressing support for and / or concerns regarding certain aspects of the proposed actions and other DEIS content. Updates have been made to the FEIS and supporting documentation in response to many of the comments and written responses to each comment, including reference to any updates that were made are provided in Table G.X.

Alternatives Considered in Detail The action alternatives – Alternative 1, 3, and 4 and the no-action alternative – Alternative 2, are considered in detail. There are 94,383 acres of NFS lands within the SERAL project area and all of the actions proposed are located on these NFS lands. The action alternatives include proposed actions which respond to current and future (to a limited degree) restoration needs.

A partnership of scientists and land managers considered experts in their field worked collaboratively to develop relevant, high-quality landscape conditions metrics which were used to inform where treatments were needed and located across the project area. The developed metrics fall into 6 main categories:

landscape resilience, wildfire risk, CSO habitat, economics, forest structure, and fire dynamics and behavior. The scenario planning tool, ForSys, was used to synthesize the information provided by the metrics. As a team, we selected two metrics as the overarching drivers to inform which areas were selected for treatment because they best represented the overall purpose of the project – To increase the landscape’s resilience to natural disturbances. These chosen objectives identified areas across the project area where the predicted fire effects were most negative and where forest structure was most departed from reference conditions. The total acres proposed for treatment was partially based on the restoration need informed by an assessment comparing existing forest structure to average pre-settlement landscape conditions and was incorporated into ForSys runs as a constraint. The preferred alternative also limits mechanical treatments within CSO PACs to areas most departed from reference conditions and to a maximum of 100 acres per PAC.

Alternative 1 (Preferred Alternative)– was developed in collaboration with Yosemite Stanislaus Solution collaborative group and incorporates the management approaches and conservation measures presented in the 2019 Conservation Strategy for the California Spotted Owl in the Sierra Nevada (hereafter referred to as the CSO Strategy). Application of the CSO Strategy is only included in Alternative 1 and made possible by the suite of proposed project-specific forest plan amendments (Appendix B, Table B-1).

Actions proposed in Alternative 1 include, forest thinning, fuel reduction, prescribed fire, fuelbreak maintenance and construction, salvage, hazard tree abatement, temporary road construction, and non-native invasive weed control and eradication.

Alternative 3 varies in comparison to Alternative 1 to comply with current management direction (USDA 2017). Alternative 3 does not include any project-specific forest plan amendments or adopt the management approaches or conservations measures presented in the CSO Strategy.

Alternative 4 was developed to comprehensively address comments, concerns, and suggestions received during scoping and further refined in response to comments received during the 45-day DEIS opportunity to comment. Like Alternative 3, Alternative 4 was developed to comply with current management direction (USDA 2017) and does not adopt the CSO Strategy or include forest plan amendments. Unlike Alternative 1 and 3, however, Alternative 4 does not propose mechanical treatments within CSO PACs, salvage, hazard tree abatement, or herbicide use for the control and eradication of non-native invasive weeds.

Comparison of Alternatives Summary Table S- 1. Proposed treatments among action Alternatives (Alt. 1, 3, and 4).

Proposed Activity How? Where? Restoration Needs Alternative 1 Alternative 3 Alternative 4

Forest Thinning

Timber Harvest, Biomass

Removal, or Mastication

In dense conifer stands where average diameters are greater than 6 inches and canopy covers are greater than 40%.

- Increase forest heterogeneity by restoring the proportion of different size and density classes across forested areas best mimic natural, historic conditions

- Reduce stand densities

- Increase the relative abundance of fire-tolerant and shade-intolerant trees.

-Provide wood products

30,498 26,471 25,234

Fuel Reduction Mastication, or piling and burning, In areas with small conifers with average diameters less than 6 inches, conifers with diameters greater than 6 inches and canopy cover less than 40%, or oaks, shrubs, or other herbaceous vegetation types generally occurring on slopes averaging less than 35% within WUI defense zones or within 250 feet of a level 2, 3, 4, or 5 road.

- Reduce and maintain low levels of surface and ladder fuels. 7,437 7,460 7,448

Fuelbreak Construction and Maintenance.

Timber harvest, biomass removal, mastication, hand thinning, or piling and burning

Where fire and fuels staff delineated the linear feature.

To achieve the goal of returning fire to the entire landscape at regular intervals. 13,430 Same as

Alt. 1 Same as

Alt. 1

Proposed Activity How? Where? Restoration Needs Alternative 1 Alternative 3 Alternative 4

Follow-up Prescribed Fire Prescribed Fire

Wherever forest thinning, fuel reduction, or fuelbreak work has occurred

-Reduce and maintain low levels of surface and ladder fuels.

- Apply or reintroduce fire to the landscape at larger, more regular intervals to mimic the natural range of fire severity and frequency.

51,366 47,361 46,292

Prescribed fire Prescribed Fire

Where no other treatments are proposed and therefore prescribed fire is the primary treatment.

- Reduce and maintain low levels of surface and ladder fuels.

- Apply or reintroduce fire to the landscape at larger, more regular intervals to mimic the natural range of fire severity and frequency.

19,763 21,007 21,304

Forest Thinning, Mastication, Fuelbreak Network, and Prescribed Fire 71,121 68,307 67,518

Summary Table S- 2. Additional Treatments Proposed to respond (in a limited manner) to future disturbance which result in tree mortality rates exceeding the natural range of variation or to maintain safe access to public lands.

Proposed Activity How? Where? When? Alternative 1 Alternative 3 Alternative 4

Salvage of Insect-, Disease-, or Drought-Killed Trees

Timber Harvest

Within 0.25 miles of Level 2, 3, 4, and 5 National Forest system (NFS) roads; in mixed conifer/fir, mixed conifer/pine, and pine dominated areas with large conifers greater than 6 inches in diameter and located outside of PACs and the proposed W & S River corridors. This equates to an area of approximately 37,243 acres where salvage may potentially occur. Salvage of insect-, disease-, or drought killed trees may not occur outside of this defined area of potential salvage. Much of the area of

When patches containing more than 75% beetle, diseased, or drought killed trees exceed 10 acres in size or when multiple mortality patches combined exceed 15 percent of a HUC 6 watershed.

-When will not exceed CWE TOC.

Yes Yes No

Proposed Activity How? Where? When? Alternative 1 Alternative 3 Alternative 4 potential salvage overlaps areas with other treatments proposed.

Only 2,416 or 3,374 acres (in Alternative 1 or Alternative 3) are unique areas without any other proposed treatments.

Salvage of Wildfire-Killed Trees

Timber Harvest Up to 500 acres per HUC 6 watershed with maximum of 3,000 acres in the project area.

In areas burned at high severity (>75% mortality) which exceed 10 % of a HUC 6 watershed -When will not exceed CWE TOC.

Yes Yes No

Hazard Tree Removal

Timber Harvest, Biomass

Removal, Felling

Along the 285 miles of public access roads traversing forest service lands in the project area.

Any tree identified as a hazard within 1 tree length of a road following current regional standards and direction.

Yes Yes No

Summary of Major Conclusions The analysis presented to address the issues related to the proposed actions and the alternatives (Section 3.01) and the ability of the proposed actions to meet the purpose and need of the project (Section 3.02) clearly demonstrate that Alternative 1 best addresses each issue and most effectively meets the purpose and needs of the project. Alternative 3 and 4 are also effective to varying degrees, but despite seemingly small differences between these alternatives and Alternative 1, their differences will likely impact implementation: economically, feasibility, and duration to completion

1. PURPOSE OF AND NEED FOR ACTION

1.01 Increase Landscape Resilience to Natural Disturbances (drought, insects, disease, wildfire) by Restoring Resilient Forest Conditions as Guided by the Natural Range of Variation

Past management actions, including fire suppression and historic logging practices, over the last one and a half centuries have extensively altered current forest conditions and ecosystem processes in the Sierra Nevada. Some of the key changes in yellow pine and mixed conifer forests include loss of old, large-diameter, fire-resistant trees and associated large, downed logs; shift in tree species composition towards shade-tolerant species; denser forests with multiple canopy layers and ladder fuels that facilitate crown fire; and more densely forested landscapes with continuous high fuel levels. These trends have led to forest stands, watersheds, and landscapes that are highly susceptible to threats such as large, high severity wildfires, widespread drought- and insect-induced tree mortality, as well as climate change (Safford and Stevens, 2017).

Modeled estimates for the Sierra Nevada indicate temperatures will increase by 5.4 to 10.8 degrees Fahrenheit (3 to 6 degrees Celsius) during the twenty-first century. Climate change projections indicate many of the low- and mid-elevation forests in the Sierra Nevada are vulnerable to conversion to woodlands, shrublands, and grasslands (USDA 2019). Projected increases in temperature and decreases in snowpack for the Sierra Nevada (Safford et al. 2012) are likely to continue the increasing trend in the size of stand-replacing fires and proportion of landscape impacted by high severity fires (Stephens et al.

2013), as well as triggering insect species population increases and subsequent tree mortality (Millar and Stephenson 2015).

Natural Range of Variation (NRV) assessments provide baseline information on the composition, structure, and function of forested ecosystems that can be compared to current conditions to develop an idea of trend over time and an idea of the level of departure from their natural state (Safford and Stevens 2017). Restoring forest composition, structure, and processes based on NRV conditions has been linked to greater resilience to wildfire, climate change, and other stressors and is a central and guiding principle of the Conservation Strategy for the California Spotted Owl in the Sierra Nevada (USDA 2019). The concept of restoring the landscape into closer alignment with historic reference conditions is rooted in the assumption that the structural composition of forests occurring in pre-settlement times, were, and would still be, more resilient to disturbances such as insects, disease, drought, and climate change, and less susceptible to large-scale, high severity wildfires. Pre-settlement reference conditions represent forests where ecological processes and adaptive capacity can continue to evolve together. Aligning the landscape with NRV is the first step towards an eventual resilient future range of variation (USDA Forest Service 2019).

The current forest structure in the SERAL project area is considerably departed from the reference conditions described in Safford and Stevens (2017) and Meyer and North (2019) (Figure 2). In both the Yellow Pine/Dry Mixed Conifer (e.g., pine-dominant mixed conifer) and Fir/Moist Mixed Conifer (e.g., fir-dominant mixed conifer) forest types, current departure is pronounced in both mid- and late-developmental stages, with the current landscape containing much more closed canopy and much less open canopy in both developmental stages. These general vegetation types represent more than two thirds of the project area (Table 1, Map 1).

Figure 2. Current landscape structure of Yellow Pine/Dry Mixed Conifer and Fir/Moist Mixed Conifer forest types compared to historic conditions.

Table 1: General vegetation types in the project area3.

General Vegetation Type Total Acres / Percent of Total (NFS and non-NFS lands)

NFS Land Acres / Percent of Total NFS Lands

(NFS lands only) Yellow Pine / Dry Mixed Conifer 73,030 / 61% 58,143 / 61%

Oak Woodland 21,421 / 18% 17,737 / 19% Shrub 15,321 / 13% 11,736 / 12%

Fir / Moist Mixed Conifer 6,753 / 6% 6,113 / 6% Herbaceous 1,104 / <1% 489 / <1%

Non-Vegetated 1,166 / <1% 562 / <1%

TOTAL4 118,795 / 100% 94,779 / 100%

A comparative assessment between the current forest structure and the reference conditions broadly informed the proportion of the project area in need of restoration as well as the type of restoration needed (Appendix A, Table A.2 and Table A.3). The restoration needs to increase resiliency include (1) increase within- and between-stand heterogeneity; (2) reduce stand densities; (3) increase the large tree component on the landscape; (4) increase the relative abundance of fire-tolerant and shade-intolerant tree species; (5) reduce surface and ladder fuels; (6) increase management by fire, both prescribed and managed wildfire;

and (7) actively restore habitat after disturbances that do not align with NRV (USDA 2019). Each of these desired conditions are further addressed in items A though G below.

Increase Forest Heterogeneity (within- and between stands) Based on the NRV assessment of conifer forest types in the SERAL project area, there is a need to increase the amount of open canopy habitat and reduce the proportion of closed canopy conditions in mid-and late-seral stages (Figure 2) to get a patchy distribution of diverse stand types across the landscape. To best mimic NRV conditions and achieve within-stand and multi-stand diversity, applied silviculture and prescribed fire treatments need to create a pattern of individual trees, clumps of trees, and openings containing various sizes of clumped trees and openings. The understory of mid- and late-seral areas should be managed for a patchy distribution of shrubs, forbs, tree regeneration patches, and bare ground to increase diversity, and reduce fuel continuity.

3 F3 derived (Huang et. al 2018); “Forest Type”.

4 F3 derived data are raster-based products and acres are approximate and explain why the total project area and NFS land acres do not equal 118,808 and 94,823 acres respectively.

Reduce Stand Densities Native insects and diseases are major contributors to natural disturbance, ecosystem dynamics, and nutrient cycling in forests. Much of the time, their impacts are minor and localized, but the synergistic effects of high tree densities, coupled with drought, create conditions that are optimal for intense insect infestations and outbreaks. Low- to mid-elevation coniferous forests of the Sierra Nevada range have recently experienced one of the largest tree mortality events in recent history. Since 2010, more than 10 million trees have been killed within the Stanislaus National Forest, according to U.S. Forest Service Forest Health Protection’s Aerial Detection Survey Data (2019). Between 2014 and 2017, tree mortality levels increased more than 100-fold in many areas of the southern Sierra Nevada. During this period, 55% of the California spotted owl (CSO) Protected Activity Centers (PACs) on the southern Sierra national forests (Sierra, Sequoia, and Stanislaus) experienced tree mortality of more than 20 trees per acre with greater loss in larger-diameter trees (USDA 2019, Koontz 2021). The vast majority of these millions of dead trees remain on the landscape, and tens of thousands of acres of live trees in the SERAL project area remain at risk to insect outbreaks and associated widespread, ecosystem-altering mortality due to current densities of live trees.

Recent results from USFS insect and disease aerial detection surveys (ADS) have shown moderate insect activity throughout the SERAL project area. While level of insect activity and tree mortality has fluctuated in recent years (2014-2021), some areas have started to become significantly impacted, particularly with pine mortality, though landscape-scale outbreaks have not yet occurred. Among recent years, 2016 saw the most activity of insect-related damage, with groups of mortality ranging from 15-30 trees/acre; activity was also clustered in the southwestern end of the project boundary, primarily in ponderosa and sugar pines. If drought and above-average temperature days persist into 2022, increased tree mortality is expected to be visible this summer and into next year (2023).

Prevention strategies for minimizing further tree mortality by reducing water stress and competition are critical. Hayes et al. (2009) reported that stand density, measured as basal area or stand density index (SDI) is the most important predictor of western pine beetle-caused tree mortality at large spatial scales in California, likely due to the effect of stand density on individual tree vigor and water availability.

Multiple studies have shown that forest thinning can relieve competitive stress among residual trees, improve their vigor, and make them less prone to successful attack by bark beetles (Restaino et al. 2019, Fettig 2012, Hayes et al. 2009).

A common metric used to quantify the level of competition in forested areas is stand density index (SDI), which is based on the number of trees per unit area—trees per acre, for example—and the diameters of those trees. It can be used to describe “how dense” trees in a forest are growing and is also an indicator of forest health. In general, higher stand densities predispose trees to damage and/or mortality from drought, bark beetles and other forest pests due to increased inter-tree competition for limited resources (Oliver 1997). Hayes et al. (2009) reported that stand density, measured as basal area or stand density index (SDI), is the most important predictor of western pine beetle-caused tree mortality at large spatial scales in California. Areas with the highest stand densities tend to experience the highest levels of tree mortality on both an absolute (trees/acre) and proportion (percentage of mortality) basis (Hayes et al. 2009, Fettig 2012). Research supports lowering stand densities as a critical component of promoting healthy, resilient forests with vigorous trees that are resilient to insect attacks (Hayes et al. 2009, Fettig 2012, Long and Shaw 2012), specifically maintaining densities below approximately 60% of the maximum SDI levels to provide for reduced density-related mortality and relatively high vigor (Oliver 1995). Modeling by Hayes et al. (2009) suggests that it might be appropriate to consider even lower SDI thresholds under some conditions, such as during elevated bark beetle populations as associated with extended drought (Fettig 2012), and also to ensure treatments are effective for some period of time before they again approach the 60% of maximum SDI threshold.

Current SDI values of conifer stands within the SERAL project area are often close to 100% of maximum SDI, which is the “theoretical maximum” (similar to the concept of “carrying capacity” in ecology) for combinations of mean diameter and density of trees. Recent research of historic SDI values in the Sierra Nevada suggests that relative SDI in pre-settlement stands averaged 23-28% of the maximum SDI, and that "tree densities on average increased by six to seven-fold while average tree size was reduced by 50%" between 1911 and 2011 (North et al. 2022). They suggest that managers could use a range of 14- 36% of maximum SDI "to create stands with higher relative SDIs on sites with greater soil moisture availability and lower potential fire intensity, and lower relative SDI values on drier, steeper slopes more prone to drought and higher intensity burns."

USDA Forest Health Protection has utilized SDI thresholds in order to identify forested areas considered to be at high risk of drought- and bark beetle-induced tree mortality and which also have a high likelihood of experiencing stand-replacing wildfire (Table 2). Current SDI values within the SERAL project area average approximately 240 in pine-dominant stands and 280 in fir-dominant stands, with more than 48,000 total acres of conifer forest stands having SDI values considered to be at “High-risk” to mortality from drought, insects, disease, and wildfire (USDA 2021(c)). Left unmanaged, high levels of inter-tree competition would persist and continue to increase. Stand vigor will stagnate, and resilience to drought-, insect-, disease-, and wildfire-related mortality will continue to decline.

Table 2. High risk SDI thresholds (USDA 2021(c)).

Forest Type Stand Density Index (SDI) Yellow Pine / Dry Mixed Conifer >220

Fir / Moist Mixed Conifer >330

Retain Large, Old, and Structurally Diverse Trees and Snags The California spotted owl (CSO) requires both highest-quality nesting and roosting habitat and sufficient habitat diversity / heterogeneity to provide for foraging (USDA Forest Service 2019). The status of the existing CSO habitat within the SERAL project area was assessed at multiple scales (PAC, Territory, HRCA, and HUC 6 Watershed).

For the purposes of SERAL, WHR size and density as well as canopy cover, were modeled using the F3 framework (Huang et al. 2018). F3 extrapolates the details of forest inventory plots (FIA) and individual-tree model outputs to a spatially-contiguous landscape by fusing tree-list field measurements, individual tree growth and yield models, remote sensing including lidar, and environmental geospatial datasets.

Using these imputed size, density, and canopy cover metrics, habitat quality categories for CSO nesting and roosting based on structural characteristics of forests were classified into two general categories: 1) highest-quality habitat and 2) best-available habitat (Table 3).

Table 3: Habitat quality categories for CSO nesting and roosting based on structural characteristics of forests.

Habitat Quality Categories Based on Structural Characteristics WHR Classification Tree Size Canopy Cover

Highest-Quality 5D, 5M, 6 More than 24-inches 40 to 100 Percent Best-Available 4D, 4M 11 to 24 inches 40 to 100 Percent

Defining habitat quality using these data provides a rough metric to quantify, in acres, the existing quality of structural characteristics of nesting/roosting and foraging habitat at multiple scales across the project area (Table 4). Table 4 presents the acres of CSO habitat at multiples, but the quantification presented was calculated simply on the size and density of the trees as the lone indicator of habitat quality. Other factors such as high-risk densities, mid-story canopy densities, high fuel loads, competition, drought conditions, insect and disease infestations, and warming temperatures are not accounted for in Table 4 but are no less important. These other abiotic parameters should be considered when assessing and defining habitat quality and when determining where retention of large, old, structurally diverse trees and snags are appropriate.

Table 4: Acres of California spotted owl habitat at multiple scales5.

Land Allocation Highest-Quality Best Available All Other Total Acres

PAC 3,157 10,696 1,868 15,722

Territory/HRCA6 3,422/3,308 19,080/13,509 11,485/1,950 33,987/18,768 All Other6 3,887/4,001 39,532/45,103 25,680/35,215 69,099/84,318

Total 10,466 69,308 39,034 118,808

Management objectives and desired conservation outcomes vary across each land allocation as it relates to CSO habitat (Table 5). Each of these objectives and desired conservation outcomes helped to identify the need for management actions across the project area. Knowing the quantity and quality of the existing habitat also provides the foundation in which to analyze each alternative’s effectiveness of maintaining quality habitat.

Table 5: California spotted owl management objectives and desired conservation outcomes.

Land Allocation Overall Management Objective Desired Conservation Outcome

PAC

Maintain high-quality habitat at occupied nest sites for the CSO while more resilient habitat is developed across the landscape

Manage PACs for resiliency and sustainability while minimizing potential near-term effects of resiliency treatments

Territory

Maintain and increase high- quality nesting, roosting, and foraging habitat while increasing habitat heterogeneity and resilience

Maintain and promote 40 to 60 percent of a territory in mature tree size classes with moderate and high canopy cover for nesting, roosting and foraging.

HRCA Manage these areas to retain their value as suitable owl habitat.

Maintain (1) at least two tree canopy layers; (2) at least 24 inches DBH in dominant and co-dominant trees; (3) a number of very large (greater than 45 inches DBH) old trees; (4) at least 50 to 70 percent canopy cover; and (5) higher than average levels of snags and down woody material.

Watershed Matrix

(HUC 6)

Restore resilient forest conditions guided by NRV

The desired conservation outcome for multiple territories comprising more than 75 percent of a watershed is to maintain 30 to 50 percent of the watershed in mature tree habitat at moderate and high canopy cover.

Currently, approximately 20% and 68% of the mapped CSO PACs structural habitat characteristics associated with the highest-quality or best-available habitat, respectively (Table 4). When locating treatments and assessing treatment needs, the management objectives and desired conservation outcomes as well as forest plan direction must be met and followed.

5 PAC and HRCA acres are located only on NFS-lands. Territory and All Other acres include non-NFS lands. Total 118,808 acres includes all lands: NFS and non-NFS lands.

6 Territory / HRCA: Two values are presented for each cell to represent the acres calculated for CSO Territories or CSO HRCAs. Alternative 1 proposes to adopt CSO Territories while Alternatives 3 and 4 would retain CSO HRCAs. Therefore, assessing the acres for either territory or HRCA is important throughout the FEIS. The values presented for Territory/HRCA do not include the overlapping PAC acres.

After a desired condition evaluation conducted for each individual territory based on the proportion of each territory comprised of the highest-quality or best-available habitat we found that all but one territory (fully located within the project area) met the desired condition to contain 40 to 60 percent of the area in mature tree size classes with moderate and high canopy cover for nesting, roosting, and foraging (in order of descending priority: 6, 5D, 5M, 4D, and 4M). In all but five of territories with at least 70% of the area within the SERAL project area, the desired condition is met either completely or primarily by best-available habitat, because either highest-quality habitat does not exist or it is very limited (e.g., less than 2%). Extra attention is needed to ensure treatments are designed to meet the desired condition while promoting resilient CSO habitat throughout the landscape.

Territories (and HRCAs) comprise more than 75% of all six of the HUC 6 watersheds located within the SERAL project area. The composition of mature tree sizes and moderate and high canopy cover falls within the desired range of 30 to 50% in each of the HUC6 watersheds (Wildlife BE Table CSO7).

However, very little (less than 10 percent) of the mature tree size classes are in the CWHR 5D and 5M categories associated with the highest-quality habitat.

Management activities that maintain the structural characteristics of highest-quality habitat while protecting it from risk of loss from high severity wildfire and other natural disturbances, require trade-offs. Balancing the retention of highest-quality habitat with necessary treatments to increase resiliency, may cause short-term decreases in habitat quality. To minimize near-term effects of resiliency treatments, such treatments should be implemented only when needed (e.g., where landscape is vulnerable to natural disturbance and loss of habitat) and should be designed to maintain the most important habitat components, such as areas of high canopy cover (more than 55 percent) in large/tall trees within PACs.

It is important to note that maintaining or improving CSO habitat is complex and requires a multi-faceted evaluation. It is imperative to avoid putting an over-emphasis or narrow focus on structural habitat characteristics and failing to consider that areas containing these desirable structural owl habitat characteristics may contain other characteristics that put them at high-risk from natural disturbances such as insect-, disease-, drought-, and high severity wildfires (e.g., high SDIs; accumulated surface and ladder fuels, and too few shade-intolerant and fire-tolerant trees).

It is well documented that a forest, PAC, or Territory containing the large trees and high canopy cover (structural characteristics of the highest-quality and best-available habitat), can also be overly dense, lack forest openings, contain lush understory vegetation which act as ladder fuels, and experience the same climate related stressors (lack of precipitation, warmer temperatures,) as the rest of the landscape across the Sierra Nevada. Characteristics which are supported indicators to assess the landscapes vulnerability to natural disturbances are just as critical to maintain and improve CSO habitat quality. To fail to comprehensively evaluate all of the habitat characteristics when assessing habitat quality and developing a project would be inconsistent with the overall CSO Strategy and fail to promote resilient CSO habitat throughout the landscape.

The SERAL project needs to find a balance between maintaining structural characteristics associated with the highest-quality and best-available habitat while promoting resilient CSO habitat across the landscape.

Increase the relative abundance of fire-tolerant and shade-intolerant trees Throughout Sierra Nevada montane forests, many decades of fire suppression have led to a major shift from dominance of shade-intolerant species, such as pines and oaks, to dominance of shade-tolerant species, primarily white fir and incense cedar (Safford and Stevens 2017). The intent here is to promote species compositions more in line with NRV, by decreasing the abundance of shade-tolerant species (for example, white fir and incense cedar) and promoting the growth of fire-resistant, shade-intolerant species (for example, ponderosa pine, sugar pine, and black oak). Historically, more fire-resistant and shade-intolerant pine and oak trees represented a greater proportion of trees across the landscape than current conditions. To correct this imbalance, these shade-intolerant species would be favored for retention during forest thinning and prescribed fire treatments. Tree removal would target smaller trees and fire-sensitive species, primarily white fir and incense cedar, that would not be as abundant under a natural fire regime (USDA 2019).

Reduce Surface and Ladder Fuels A mosaic or NRV of vegetation and fuel load conditions across the landscape was most likely commonly found in the Sierra Nevada, but that was in the context of a frequent fire regime when surface and ladder fuels were regularly consumed. Historically fires burned so often in yellow pine / mixed conifer forests that it is unlikely that much large woody material survived repetitive fire processes long enough to decompose fully (Skinner 2002 in Safford and Stevens 2017). Accumulated surface and ladder fuels, including coarse woody debris and tall, dense shrubs, increase the risk of higher flame lengths, increase residence or burning time, increase resistance to control a fire, and/or may increase fire severity (i.e., vegetation mortality). Collectively these effects are likely to result in loss of wildlife habitat and community infrastructure and impact the stability and health of soil and water.

The suite of 40 fire behavior fuel models (Landfire 2016 [updated for tree mortality conditions in 2017], Scott and Burgan 2005) enables an assessment of different dead and downed fuel and understory vegetation loading and structural categories that contribute to the leading edge, or head of the fire. This fuel modeling effort provides a descriptive and partially qualitative assessment of the existing understory vegetation and dead fuel loads across the landscape within the SERAL project area and spatially outlines the need for treatment (Table 6).