TAHOE NATIONAL FOREST, AMERICAN RIVER RANGER DISTRICT BIG HOPE PROJECT FIRE & FUELS SPECIALIST REPORT

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1 TAHOE NATIONAL FOREST, AMERICAN RIVER RANGER DISTRICT BIG HOPE PROJECT FIRE & FUELS SPECIALIST REPORT Introduction In August 2013, the American Fire burned approximately 27,400 acres, 22,500 acres on the American River Ranger District of the Tahoe National Forest and 4,900 acres on adjacent private lands. The fire burned roughly 38 percent of the North Fork of the Middle Fork of the American River Watershed, with portions of the Black, Secret, Manila and Screwauger Canyon watersheds experiencing the highest vegetative burn severity resulting in large areas of standing dead trees. The Big Hope Project is being proposed as a management response to the American Fire. The proposed management actions are designed to recover the economic value of fire-killed trees, reduce public safety hazards along portions of roads and trails and at trailheads and recreation sites, reduce the danger and difficulty of suppressing future wildfires, and re-establish forested conditions and habitats in burned forest stands. Purpose and Scope The purpose of this report is to analyze and compare predicted current and future wildfire characteristics from the proposed alternatives (action and no action) addressed in the Big Hope Project Environmental Analysis (EA) on the American River Ranger District, Tahoe National Forest, Placer County, California. In particular, this analysis will focus on the following effects: The direct effect of the proposed action and no action alternatives on existing and future wildfire potential characteristics within the treated areas. The indirect effect of the proposed action and no action alternatives on existing and future wildfire characteristics and probable control options adjacent to the treated areas. The cumulative effect of the proposed action and no action alternatives on existing and future wildfire potential characteristics within the Big Hope Analysis Area. The direct, indirect and cumulative effects of the proposed action and no action alternatives on air quality. Background Before the American fire, the Big Hope Project area was comprised of even-aged mixed conifer plantations, dense white fir stands and scattered uneven aged sierran mixed conifer stands. There were no recorded instances of wildfire in the majority of the fire area since 1908, the earliest reliable date available. Elevations in the fire area range from 2240 feet above sea level along the North Fork of the Middle Fork of the American River to 7080 feet at Duncan Peak. Slopes range from near flat to near vertical. Prior to European settlement, the average natural fire return interval for the Big Hope area ranged from 11 to 26 years with more than 90% of the landscape burning less than 16 years (Safford et. al., 2011). The landscape has been heavily influenced over the last 100 years by mining, grazing, logging, and fire suppression activities. At the stand level, the combination of these activities had 1

2 created overstocked stands with high accumulations of surface fuels, often under an unbroken fuel ladder of understory vegetation extending to the forest canopy. Illustration 1 below shows the 2013 American Fire, with historic fire areas shown from Illustration 1. American River Ranger District Fire History Post-fire conditions were assessed through remote sensing and field observations. The burn severity of the fire was mapped utilizing The Rapid Assessment of Vegetation Condition after Wildfire (RAVG) process. The RAVG products are based on a seven-class basal area loss layer modeled from the relative differenced Normalized Burn Ratio surface. In the context of RAVG analysis, basal area loss measures the percent change in basal area or tree cover (relative number of live trees on the site) from the pre-fire condition. Basal area loss is expressed as four classes of percent change in tree cover and is measured in square feet. Basal area loss does not describe a permanent loss of basal area within a forest, but simply describes the amount of change in the live tree cover immediately (30 days after) wildfire containment. The seven-class layer is grouped into four classes for the Geographic Information Systems (GIS) overlay analysis and subsequent RAVG table and map generation. The data tables and maps are created using existing vegetation maps overlain with basal area loss results. Existing Vegetation Types (EVTs) are grouped and used for the GIS overlay analysis. The seven-class basal area loss layer contains the following classes: Class 1 = 0% basal area (BA) loss 2

3 Class 2 = 0% - less than 10% BA loss Class 3 = 10% - less than 25% BA loss Class 4 = 25% - less than 50% BA loss Class 5 = 50% - less than 75% BA loss Class 6 = 75% - less than 90% BA loss Class 7 = 90% or greater BA loss The seven-class basal area loss layer is grouped into the following four classes for the GIS overlay analysis: Class 1 = 0% - less than 25% BA loss Class 2 = 25% - less than 50% BA loss Class 3 = 50% - less than 75% BA loss Class 4 = 75% - 100% BA loss In the low severity burn areas (GIS overlay classes 1 and 2), fifty to ninety percent of existing surface fuels were consumed, with most trees less than ten inches diameter at breast height (dbh) killed. Most trees over ten inches dbh have varying degrees of scorch, but initially survived. In the moderate severity burn areas (GIS overlay classes 2 and 3), pockets of trees in all size classes are completely killed. In the high severity Burn areas (GIS overlay classes 3 and 4), up to one hundred percent of the trees are dead, with most foliage completely consumed. Surface fuels and associated ground cover in moderate and high severity burn areas has been greatly reduced, if not entirely eliminated. Illustration 2 below shows the RAVG burn severity for the American Fire. The areas of highest fire severity were not confined to specific elevations, slopes, or aspects. Overall, fire severity was a mix of low and moderate severity with several large patches of high burn severity. 3

4 llustration 2. RAVG burn severity for the American Fire Table 1 quantifies the Fire Severity within the Big Hope Project Area and the total American Fire Area. Table 1.Basal Area Mortality from the American Fire Fire Severity (BA Mortality) 0-50% 50-75% > 75% Total Project Area (Acres/Percent) 4,354 Acres 43% 923 Acres 9% 4,811 Acres 48% 10,088 Acres* Total American Fire Area (Acres/Percent) 16,879 Acres 62% 2,325 Acres 8% 8,222 Acres 30% 27,436 Acres *The total acreage of the burn severity categories within Big Hope treatment areas is less than the total acreage of proposed treatment area. 477 acres of the treatment unit area fall outside of the RAVG burn severity GIS data. Guiding Regulations and Policies The Big Hope Fire Recovery Project is designed to fulfill the management direction specified in the 1990 Tahoe National Forest Land Resource Management Plan (LRMP) as amended by the 2004 Sierra Nevada Forest Plan Amendment (SNFPA). Proposed management activities are designed to comply with the standards and guidelines as described in the LRMP and SNFPA. The American Fire area falls within six Management Areas (MAs) described in the LRMP: 4

5 Management Area 84 (Humbug-Sailor). This MA is located on the gently to moderately sloped uplands overlooking the North Fork of the American River canyon. Of the approximately 215 acres of the fire area that fall within this MA, 50 acres of restoration treatments including tree planting, salvage logging and roadside hazard tree removal are proposed. The major resource emphasis for this MA is vegetation management. Management Area 90 (Divide). This MA encompasses the Foresthill Divide Road from the Chicken Hawk area to the junction of the Soda Springs Road. Of the approximately 2080 acres of the fire area that fall within this MA, 1100 acres of restoration treatments including tree planting, salvage logging and roadside hazard tree removal are proposed. Roadside visual quality and fuel break construction and maintenance are major resource management emphases for this MA. Management Area 91 (Sunflower). This MA is encompassed by Sunflower Hill on the north, MA 89 (French) on the south and east, and Duncan Peak on the west. Of the approximately 1635 acres of the fire area that fall within this MA, 185 acres of restoration treatments, primarily roadside hazard tree removal are proposed. Timber and range management are major resource management emphases for this portion of MA 91. Management Area 92 (Peavine). Approximately acres, 68 percent of the American fire area falls within this MA. Approximately 8100 acres of restoration treatments including tree planting, salvage logging and roadside hazard tree removal are proposed in this MA. Timber and range management are major resource management emphases for MA 92. Management Area 98 (Eldorado). This MA is located primarily in the Middle Fork of the American River watershed. Of the approximately acres of the fire area that fall within this MA, 1060 acres of restoration treatments including tree planting, salvage logging and roadside hazard tree removal are proposed. Timber and range management are major resource management emphases for this portion of MA 98 Management Area 99 (Mosquito). This MA contains the roadside corridor (visual foreground) of the Mosquito Ridge Road from the western forest boundary to Red Star Ridge. Of the approximately 110 acres of the fire area that fall within this MA, 70 acres roadside hazard tree removal are proposed Roadside visual quality and fuel break construction and maintenance are major resource management emphases. Management Area 104 (Grouse Falls). This MA is located on Grouse Creek, a mile above its confluence with the North Fork of the Middle Fork American River, just outside the American Fire perimeter. The falls are in a steep, rugged canyon, reached only by a primitive trail. Because of its location and the steep canyons of Grouse Creek and North Fork of the Middle Fork of the American River, the area receives limited recreation use. No restoration activities are planned for this MA. Management Intent and Objectives The 2004 SNFPA Appendix A, Part D directs the forests to determine the need for ecosystem restoration projects following large, catastrophic disturbance events (including wildfire) and that salvage harvest of dead and dying trees may be conducted to recover the economic value of this material and to support objectives for reducing hazardous fuels, improving forest health, reintroducing fire, and/or re-establishing forested conditions. 5

6 Broad-scale forest plan goals include: Treating fuels in a manner that accelerates dispersal of coarse woody debris compared to untreated areas, thereby contributing to more effective fire management. Treating hazardous fuels in a cost-efficient manner to maximize program effectiveness. Actively restoring fire-adapted ecosystems by accelerating development of mature forest habitat. Strategically placing treatments across landscapes to interrupt potential fire spread and facilitate wildfire management tactics and objectives. Overall Big Hope Project objectives for fire and fuels management include: Reducing volume of standing dead timber, thereby reducing the danger and difficulty of managing future wildfires. Reducing snag hazards on roads, trails and other areas that typically provide access, egress and staging areas for fire suppression, fuels management, and other forest operations and projects. Reestablishing the fuel characteristics of resilient, fire-adapted forests. Intensity Criteria Pertaining to Resource The effects of treatment on fuels and potential fire behavior are evaluated using the following measurement indicators. Surface Fuel Load: The predicted surface fuel loads (tons per acre), as computed by the Fire and Fuels Extension to the Forest Vegetation Simulator (FFE/FVS) are reported under the direct and indirect effects for each alternative. FFE/FVS is a model used to summarize current stand conditions, predict future stand conditions under various management alternatives, and update inventory statistics (Dixon, 2002). Fuel loads are reported in tons per acre for the following fuel classes: Forest duff. Forest duff is the fermentation and humus layers of the forest floor. It does not include the freshly cast material in the litter layer. The top of the duff is where needles, leaves, and other castoff vegetative material have noticeably begun to decompose. Individual particles usually will be bound by fungal mycelium. When moss is present, the top of the duff is just below the green portion of the moss. The bottom of the duff is mineral soil. Forest Litter. Forest Litter is the surface layer of the forest floor and consists of freshly fallen leaves, needles, twigs, bark, and fruits (Brown 1974). Downed woody material from one to three inches in diameter. Downed woody material from three to six inches in diameter. Downed woody material from six to twelve inches in diameter. Downed woody material greater than twelve inches in diameter. Herbs (grasses, forbs, etc.) and shrubs. Standing trees greater than three inches dbh, both live trees and dead snags 6

7 The volume and condition of surface fuels is critical in determining fire potential. Fine (less than three inches in diameter) dead surface fuels respond to ambient environmental conditions and determine the rate of spread and intensity at the fire front. Larger dead surface fuels respond more slowly to environmental conditions, but may extend fire residence times and be more difficult to extinguish. Live surface fuels typically become more susceptible to ignition as the dry season progresses. In the post-fire environment, standing dead trees greater than three inches dbh present considerable challenges to fire management resources. These snags are not only susceptible to ignition from wildfires, but are more likely to fall suddenly the longer they stand. Fire suppression forces often cannot safely attack fires burning in areas of high snag density, regardless of fire intensity or rate of spread. The volume of surface fuels remaining after the American Fire vary with fire intensity, but begin to rise quickly as new vegetation colonizes the burned area, and fire killed and damaged vegetation begins to decompose and fall to the forest floor. The volume of standing dead trees peaks within a year of the fire event, then gradually declines as the trees fall. Reduced surface fuel volumes and lower volumes of standing dead snags greater than three inches dbh under the proposed action represent desired conditions for fire and fuels management. Flame Length: Flame length (measured in feet) is influenced by fuel type, fuel arrangement, fuel moisture, and weather conditions. Fuel type and fire intensity in turn influence fire line production rates by different suppression resources. Increased flame lengths indicate an increase in fire intensity and the likelihood of high mortality in naturally regenerated, newly planted and fire-survived stands. Predicted flame lengths that do not significantly increase under the proposed action represent acceptable conditions for fire and fuels management. Tools Used to Predict Impacts Effects of the proposed alternative on fuels and future wild fire characteristics are compared to the no-action alternative. FFE/FVS was used predict surface flame lengths, surface fuel loads, and standing dead timber greater than three inches dbh before and after the proposed treatments. Forest stand data collected before the fire was burned in a simulated wildfire under severe and moderate fire weather conditions. These outputs were then compared to post-fire field observations for representative accuracy. The model was used to quantify existing conditions and to predict the effects of alternative treatments on fuel loads and high intensity fire potential. Modeled results are used to highlight the relative differences resultant of the proposed action against the no action alternative. Assumptions Made: Baseline stand data is representative of conditions in the pre-fire Big Hope Project area. Model outputs predict existing and future potential wildfire effects under severe and moderate fire weather and fuel moisture conditions within the treatment areas. While rare, severe weather conditions occur annually during the summer fire season. Historically, ignitions occurring under severe weather and fuel moisture conditions exceed initial attack suppression capabilities and become large, high severity wildfires. 7

8 Alternative 1, the Proposed Action (see Chapter 2 of the EA for a full description of the proposed action) Ground-based harvesting and follow-up fuels treatments Fire killed trees greater than twelve inches dbh would be considered for commercial timber harvest. Non-merchantable fire killed trees may be felled and left in place, or left standing. In the majority of the treated stands activity generated fuels will be lopped and scattered to a depth not to exceed 18 inches (particularly in areas of low to nonexistent surface fuels) as a follow-up fuels treatment and site preparation for tree planting. Mechanical treatments may be used to disperse activity fuels and prepare sites for tree planting. Mechanical treatments may include masticating, or machine piling and burning activity and residual fuels. Tree planting activities would include site preparation (as needed), variable spacing, cluster planting, establishment of founder stands, or natural regeneration (where appropriate), and follow up release treatments. Cable harvesting and follow-up fuels treatments Fire killed trees greater than twelve inches dbh would be considered for commercial timber harvest. Non-merchantable fire killed trees may be felled and left in place or left standing. In the majority of the treated stands activity generated fuels will be lopped and scattered to a depth not to exceed 18 inches (particularly in areas of low to nonexistent surface fuels) as a follow-up fuels treatment and site preparation for tree planting. Hand treatments may be used to disperse activity fuels and prepare sites for tree planting. Hand treatments may include lopping and scattering to a depth not to exceed 18 inches or piling and burning activity and residual fuels. Tree planting operations will include site preparation (as needed), variable spacing, cluster planting, establishment of founder stands, or natural regeneration (where appropriate), and follow up release treatments. Roadside hazard tree removal Hazard trees would be identified using the Hazard Tree Guidelines for Forest Service Facilities and Roads in the Pacific Southwest Region (Angwin et al. 2012). Merchantable fire-killed trees would be felled and removed. Non-merchantable fire killed trees may be felled and left in place, or left standing. (The analysis of direct and indirect effects assesses standing snags greater than 3 inches dbh (in tons per acre).) In the majority of the treated areas activity generated fuels will be lopped and scattered to a depth not to exceed 18 inches (particularly in areas of low to nonexistent surface fuels) as a follow-up fuels treatment and site preparation for tree planting. Mechanical treatments within the hazard tree removal areas may be used to disperse activity fuels and prepare sites for tree planting. Mechanical treatments may include masticating, or machine piling and burning activity and residual fuels. 8

9 Tree planting operations will include site preparation (as needed), variable spacing, cluster planting, establishment of founder stands, or natural regeneration (where appropriate), and follow up release treatments. Tree planting in high severity burn areas Tree planting will generally occur in identified areas of moderately high to very high fire severity, as well as all salvage harvest areas and identified areas of roadside hazard tree removal. Tree planting operations will include site preparation (as needed), variable spacing, cluster planting, establishment of founder stands, or natural regeneration (where appropriate), and follow up release treatments. Alternative 2, No Action No treatments would occur in any areas. DIRECT, INDIRECT AND CUMULATIVE EFFECTS ANALYSIS Alternative 1, Proposed Action American Fire area includes approximately 22,500 acres of national forest land and 5,000 acres of private land. Within this area, approximately 3,443 acres (thirteen percent) would be salvage logged. 5,519 acres (fifteen percent) would host roadside hazard tree removal operations. A total of 7,295 acres (twenty seven percent) would be reforested. Under the proposed action, approximately thirty eight percent of the entire fire area would host fire restoration treatments (Table 2.) Table 2. Summary of the Big Hope Project proposed action treatment activities Activities Acres Treated Total Salvage Harvest 1 3,443 Tractor Salvage Harvest 3,008 Aerial Salvage Harvest 435 Total Roadside Hazard Tree Removal 2 5,519 Total Tree Planting 3 7,295 Tree Planting Areas With Mechanical Site Preparation and Release 3,624 Mastication on 2,476 acres Mechanical Piling on 1,148 acres Tree Planting Areas With Hand Site Preparation and Release 445 Tree Planting Areas With Mechanical Release Only (no site preparation) 1,332 Tree Planting Areas With Hand Release Only (no site preparation) 1,894 Total Footprint of Treatment Areas 4 10,566 1 Roadside hazard tree removal overlaps 2,248 acres of the identified salvage harvest and planting areas. 2 Calculation assumes 200 feet along both sides of road segments; however, hazard tree frequencies and distances are extremely variable. 3 The tree planting total includes the 3,443 acres planned for planting within salvage harvest areas. 1 Roadside hazard tree removal overlaps 2,248 acres of the identified salvage harvest and planting areas. 2 Calculation assumes 200 feet along both sides of road segments; however, hazard tree frequencies and distances are extremely variable. 3 The tree planting total includes the 3,443 acres planned for planting within salvage harvest areas. 4 The total footprint acreage figure does not include overlap with other treatment areas. It represents the actual landscape footprint. 9

10 4 The total footprint acreage figure does not include overlap with other treatment areas. It represents the actual landscape footprint. Direct and Indirect Effects Analysis Salvage Harvest and Roadside Hazard Tree Removal Treatment in these areas is assumed to consist of removal of merchantable fire-killed trees. Fire-killed trees are burned trees that either (1) have no green needles or (2) meet the criteria of a 0.7 Probability of Mortality (Pm) in the Marking Guidelines for Fire-Injured Trees in California, Report # RO (Smith and Cluck 2011). A major criterion used would be evidence of significant wood boring and bark beetle activity as detailed in (Smith and Cluck 2011). Commercial-sized trees being considered for this project are a minimum of 12 inches dbh, however, the minimum diameter could increase during project implementation to ensure harvest of sound, utilizable timber. Non-commercial trees may be felled and left on site to reduce public safety hazards along roads, trails, and recreation sites, to reduce overhead hazards of future tree planting efforts or to provide soil stability. Non-commercial trees that remain standing would eventually fall and add to surface fuel loadings on site. Where feasible and appropriate, activity generated fuels (logging slash, etc.) would be removed by burning or biomass utilization. Activity generated fuels not removed would be lopped and scattered to a depth not to exceed 18 inches or masticated (particularly in areas of low to nonexistent surface fuels) as a follow-up fuels treatment and site preparation for tree planting. Hazard trees would be felled along roads and recreation trails, as well as at trailheads and other recreation sites within the Big Hope Project Area. Hazard trees with commercial value (generally greater than 10 inches dbh depending on timing of removal) would be commercially harvested. The limbs and tops of cut trees would generally be lopped and scattered to a depth not to exceed 18 inches. Non-merchantable hazard trees could also be felled and left on site. Chart Series 1 illustrates expected results from salvage harvest and hazard tree removal in areas of high burn severity. Chart 1.1 Average Surface Fuels in High Severity Burned Stands 10

11 50.00 Surface Fuel High Severity Stands Average Tons per Acre Existing Condition 12 in min dbh Cut Year Chart 1.1 illustrates the predicted trend in surface fuel loads under the proposed action ( 12 in min dbh Cut ) and no action ( Existing Condition ) alternatives. Prior to the fire there was an average of approximately 30 tons per acre of total surface fuels. After the fire, there is approximately 10 tons per acre. If no action is taken, average surface fuels would increase to approximately 45 tons per acre within 20 years. Under the action alternative surface fuels consumed in the 2013 fire are replaced with material brought to the ground with the salvage harvest. Because the majority of large snags would be removed and not allowed to remain in the stand, fuel loadings are expected to remain relatively constant within the treatment areas for the next 20 years. No activity fuels are removed in this illustration, any activity fuels removed by site preparation or plantation release activities could further lower fuel loads under the proposed action. Chart 1.2 Average Number of Snags Greater Than 3 dbh in High Severity Stands Standing Snags > 3" dbh High Severity Stand Average Tons per Acre Existing Condition 12 in min dbh Cut Year Chart 1.2 illustrates the predicted volume of standing snags greater than 3 inches dbh under the proposed ( 12 in min dbh Cut ) and no action ( Existing Condition ) alternatives. While not completely eliminated, the hazard to future firefighters, forest workers and forest visitors 11

12 from falling snags in the treatment areas are reduced from approximately fifty tons per acre under the no action alternative, to under ten tons per acre under the proposed action. Chart 1.3 Average Flame Lengths in High Severity Stands FL (feet) Flame Length High Severity Stands Average Year Existing Conditions/High Fire Danger Proposed Action 12 min dbh Cut/High Fire Danger Existing Conditions/Moderate Fire Danger Proposed Action 12 min dbh Cut/Moderate Fire Danger Chart 1.3 illustrates predicted future flame lengths under the proposed ( 12 in min dbh Cut ) and no action ( Existing Conditions ) alternatives during high and moderate fire danger conditions in the fire areas that experienced high severity in the American Fire. In both alternatives, predicted flame lengths increase to over ten feet under high fire danger conditions, and remain under four feet (generally recognized to be the limit of control for direct attack fire suppression methods (Deeming et al. 1977)) under moderate fire danger conditions (which is approximately ninety percent of overall fire conditions, based on fire weather records from the last ten years). This increase is primarily due to the increased ratio of fine dead surface fuels to larger and live fuels after the fire, and the predicted higher midflame windspeeds due to reduced vegetation in the burned area. While the predicted flame lengths are initially somewhat higher under the proposed action, they become statistically equal over time. No activity fuels are removed in this illustration, any fuels removed or dispersed by site preparation or plantation release activities could further reduce flame lengths under the proposed action. Chart Series 2 illustrates expected results from salvage harvest and hazard tree removal in areas of low to moderate fire severity. Chart 2.1 Average Surface Fuels in Low and Moderate Severity Burned Stands 12

13 Tons per Acre Surface Fuel Low/Moderate Severity Stands Average Year Existing Condition 12 in min dbh cut Chart 2.1 illustrates the predicted trend in surface fuel loads under the proposed ( 12 in min dbh Cut ) and no action ( Existing Condition ) alternatives. Prior to the fire there was an average of approximately 30 tons per acre of total surface fuels. After the fire, there is approximately 10 tons per acre. If no action is taken, average surface fuels would increase to approximately 20 tons per acre within 20 years. The similarity in results for both alternatives reflected in this chart illustrates the relatively low number of trees greater than 12 inches dbh killed by the fire in stands with low to moderate vegetation burn severity, thus the lower volume of salvage logging activity generated fuels. Surface fuels brought to the ground with the salvage harvest are initially somewhat higher than those accumulating under the no action alternative, but become statistically equal over time. The surface fuel load increases at a virtually equal rate under both alternatives. No activity fuels are removed in this illustration, any fuels removed by site preparation or plantation release activities could further lower fuel loads under the proposed action. Chart 2.2 Average Number of Snags Greater Than 3 dbh in Low and Moderate Severity Stands Standing Snags > 3" dbh Low/Moderate Severity Stands Average Tons per Acre Existing Condition 12 in min dbh cut Year 13

14 Chart 2.2 illustrates the predicted volume of standing snags greater than 3 inches dbh under the proposed ( 12 in min dbh Cut ) and no action ( Existing Condition ) alternatives. While not completely eliminated, the hazard to future firefighters, forest workers and forest visitors from falling snags in the project area are reduced from approximately six tons per acre under the no action alternative, to under two tons per acre under the proposed action. Chart 2.3 Average Flame Lengths in Low and Moderate Severity Stands FL (feet) Flame Length Low/Moderate Severity Stands Average Year Existing Conditions/High Fire Danger Propsed Action 12 min dbh Cut/High Fire Danger Existing Conditions/Moderate Fire danger Proposed Action 12 min dbh Cut/Moderate fire Danger Chart 2.3 illustrates predicted future flame lengths under the proposed ( 12 in min dbh Cut ) and no action ( Existing Condition ) alternatives. In the low to moderate burn severity stands, predicted flame lengths remain under four feet in both alternatives and under moderate and high fire danger conditions for twenty years. Predicted flame lengths are statistically equal. No activity fuels are removed in this illustration, any fuels removed or dispersed by site preparation or plantation release activities could further reduce flame lengths under the proposed action. Plating Trees in Burned Areas Areas of national forest lands that experienced moderate to high vegetation burn severity effects would be hand planted with 1 and 2-year-old mixed conifer seedlings. Planting strategies designed meet desired future conditions may include variable spacing, cluster planting, and establishment of founder stands. Surviving and colonizing hardwoods would be retained and encouraged. Site preparation and future release activities would be determined by planting area conditions (e.g., slopes, soils, quantity of downed trees, quantity of small diameter snags, resprouted vegetation, etc.). Site preparation and future release are done utilizing mechanized equipment or by hand, based on site conditions. Fire killed and/or resprouting vegetation within planting areas (standing and/or on the ground) may be lopped and scattered, masticated, chipped, or piled and burned to provide a safe, operable planting area and to benefit future fire and fuels management objectives (see explanation of tree planting strategy in Chapter 2 of the EA). To release the planted seedlings, competing vegetation may be similarly treated within one, three, or five years after planting. The effects of reforestation on future wildfire behavior cannot be accurately modeled for the Big Hope Project due to the highly variable nature of existing fuel conditions, and the 14

15 different locations, degrees, and techniques of site preparation, planting, and plantation release activities. Consideration of the purpose, need and long term objectives of planting trees in the Big Hope Project support the following basic conclusions: Proposed planting areas generally burned with moderate to high severity in the American Fire. Surface fuels are greatly reduced, if not completely consumed. This reduction of fuels reduces the likelihood, size, and severity potential of future wildfires until these surface fuels regenerate. Site preparation and plantation release activity generated fuels that are not removed from the site (e.g. mastication) would be dispersed to the surface, accelerating decomposition and reducing heavy concentrations of dead fuel. Depending on existing surface fuel conditions (quantities), this management strategy may increase the risk of plantation loss to wildfire until the activity fuels decompose. Site preparation and plantation release activities that remove fuel (e.g., burning, biomass utilization) would maintain low surface fuel loads and prevent the development of ladder fuels, significantly decreasing the probability of high intensity fire for ten or more years into the future. Summary of Direct and Indirect Effects for Alternative 1 Significant reduction to near total elimination of surface and small understory (ladder) fuels is a persistent characteristic of the areas that burned with moderate and high severity effects within the Project Area. This change in fuel loading and composition is expected to reduce wildfire intensities and rates of spread for several years. However, high snag densities and a complex arrangement of fallen trees, broken tops and branches intermixed and suspended within an increasingly heavy shrub component would eventually limit the ability of firefighters to safely and effectively control future wildfires, particularly in strategic locations that could be used for future fire suppression actions. Salvage logging and planting trees in moderate and high fire severity fire areas would generate some surface fuel, but the important factors in future fire behavior would be the naturally sprouting vegetation, the planted trees, and the wildfire-reduced volume of fine dead surface fuels. Reestablishment of a mixed conifer forest through planting would result in a wildfire risk (principally to the planted trees) in or immediately adjacent to these plantations. The potential for higher fire severity increases approximately five years after planting. Without plantation management, predicted fire severity increases until the trees overtop competing shrubs and begin to self-prune. Salvage logging and planting trees in low fire severity fire areas may generate concentrations of surface fuel, principally where the trees are felled. These pockets would produce a temporary and localized increase future fire severity potential as the activity fuels disperse and decompose. Since the majority of the dominant and co dominant trees in these areas survived the fire, naturally sprouting vegetation and associated development of surface and ladder fuels is expected to be less than moderate and high severity stands. The American fire reduced mean surface fuel loads by over sixty percent even in low severity burn areas. Consequently, the areas of elevated fire severity potential (from harvest generated slash) are relatively small, isolated, and surrounded by large areas of drastically reduced fuels. 15

16 The primary adverse effect of the proposed action is the risk to reforested areas as surface fuels accumulate and the planted trees grow. While fire severity levels would remain reduced throughout the burn area, future fires could ruin tree planting efforts under high fire danger conditions. Established plantation management practices (Site preparation, variable stocking, thinning, pruning, weeding, brush removal, etc.) greatly reduce the possibility of a plantation killing wildfire. Mastication of competitive vegetation in or near plantations would contribute positively to tree health and vigor, but would not necessarily reduce future fire danger due to fuels remaining on site. Removal of on-site fuels through burning or biomass utilization is most effective in reducing the possibility of a plantation killing wildfire. The American Fire dramatically reduced surface fine fuel loads, old deep duff and litter layers, and ladder fuel continuity across a wide area. This overall reduction in potential severe fire behavior is expected to persist for years. The proposed action would temporarily contribute to the surface fuel load, but not enough to significantly increase fire danger. As they grow and without future management, plantations could be vulnerable to wildfires under high fire danger conditions. Cumulative Effects for Alternative 1 In order to understand the contribution of past actions to the cumulative effects of the proposed action and alternatives, this analysis relies on current environmental conditions as a proxy for the impacts of past actions. This is because existing conditions reflect the aggregate impact of all prior human actions and natural events that have affected the environment and might contribute to cumulative effects. This cumulative effects analysis does not attempt to quantify the effects of past human actions by adding up all prior actions on an action-by-action basis. There are several reasons for not taking this approach. First, a catalog and analysis of all past actions would be impractical to compile and unduly costly to obtain. Current conditions have been impacted by innumerable actions over the last century (and beyond), and trying to isolate the individual actions that continue to have residual impacts would be nearly impossible. Second, providing the details of past actions on an individual basis would not be useful to predict the cumulative effects of the proposed action or alternatives. In fact, focusing on individual actions would be less accurate than looking at existing conditions, because there is limited information on the environmental impacts of individual past actions, and one cannot reasonably identify each and every action over the last century that has contributed to current conditions. Additionally, focusing on the impacts of past human actions risks ignoring the important residual effects of past natural events, which may contribute to cumulative effects as much as human actions. By looking at current conditions, we are sure to capture all the residual effects of past human actions and natural events, regardless of which particular action or event contributed those effects. Third, public scoping for this project did not identify any public interest or need for detailed information on individual past actions. Finally, the Council on Environmental Quality issued an interpretive memorandum on June 24, 2005 regarding analysis of past actions, which states, agencies can conduct an adequate cumulative effects analysis by focusing on the current aggregate effects of past actions without delving into the historical details of individual past actions. The cumulative effects boundaries considered in this analysis begin with the proposed treatment areas themselves. Changes in fire behavior potential are most readily evident and easily modeled within the treated areas. FFE/FVS predictions of future fuel characteristics 16

17 and surface flame length was modeled for twenty years after the 2013 fire and salvage logging operations. After twenty years successfully reforested areas are expected to begin overtopping resprouting shrubs. In other areas, brush and shrubs will become the dominant vegetation for the foreseeable future. The proposed treatments are also expected to positively influence wildfire behavior outside of the treated areas. (Finney 1999) suggests that fire spread rates can be reduced, even outside of treated areas, if a fire is forced to flank areas where fuels have been reduced or otherwise modified. The treated areas, particularly those with reduced fuels from site preparation and/or plantation release activities would slow the spread and reduce the intensity of oncoming fires, thereby reducing severe fire effects in both treated and untreated areas. There are also cumulative effects associated with the American fire area as a whole. Typically, wildfire scars support varying but consistently reduced degrees of fire intensity many years after they occur (Collins et al 2008). As a result of the fuels consumed in the 2013 fire, it is likely wildfires within the American fire perimeter will be smaller, less destructive and easier to control for ten or more years to come, depending on the fuel conditions at the point of ignition. Future fires will likely exhibit lower intensity and rates of spread upon entry into the American area for at least the next five to ten years. Expected effects of the Big Hope proposed actions, together with cumulative effect of the fire itself are less intense, more easily and economically managed future wildfires within the entire Big Hope analysis area. Suppression and suppression repair actions taken during and immediately after the American Fire affected the environment. They included aerial drops of water and fire retardant chemicals, burning and chipping of fuels along control lines, construction of containment lines by heavy equipment and hand crews, live-tree and snag falling, and construction of personnel and equipment staging areas, helicopter landing areas, and cleared areas to provide for firefighter safety. Fire suppression repair activities included returning roads, containment lines, staging areas, helicopter landing areas, safety zones to as close to preincident conditions as possible, applying erosion control measures to containment lines; removing debris resultant of suppression actions from stream channels, and covering exposed soil with natural vegetation to protect soil structure. These activities alter the environment by removing vegetation, compacting soils or introducing or spreading invasive species. Such activities generally caused localized effects, but are not considered significant relative to fuels, fire, and air quality. Burned Area Emergency Rehabilitation (BAER) activities were taken to mitigate effects of the fire which might cause imminent danger to life, property, or natural resources. Rehabilitation efforts focused on restoration and improvement of drainage functions, mastication of dead vegetative material to reestablish soil cover in high severity burn areas, reduce erosion and limit damage to roads. Actions taken for BAER did not have measurable effects relative to fuels, fire, or air quality. The Hoedad Planting Project is designed to re-establish young plantations on approximately 557 acres that were lost during the American Fire (Illustration 3). This includes site preparation prior to planting and future release (manual or mechanical removal of competing vegetation). The site preparation is being done to reduce competing vegetation around 17

18 planted seedlings. Since this project reestablishes previously existing young plantations, does not involve salvage of merchantable timber, is widely dispersed and covers approximately two percent of the fire area, it is not considered significant relative to fuels, fire, and air quality. Illustration 3. Hoedad Planting Project Area The Ford Roadside Hazard Tree Removal Project (Illustration 4) is designed to remove roadside hazard trees (approximately 5 miles or up to 250 acres) within the American Fire area on two motor ways that provide access to large portions of the District and are heavily used by the public. The majority of hazard trees proposed for removal occur in high severity burned areas; however, hazard trees in mixed severity burned areas would also be included wherever burned trees pose a risk to the roadway. Since this project covers approximately one percent of the fire area, it is not considered significant relative to fuels, fire, and air quality. Illustration 4. The Ford Roadside Hazard Tree Removal Project 18

19 The Tahoe National Forest personal use firewood program allows the purchase of a permit to cut and remove wood for fuel from National Forest lands. Most of this material consists of fallen trees found along forest roads, and non-merchantable logs from past logging operations. Unused material left behind by firewood gathering does not contribute significantly to the surface fuel loading due to the dispersed nature of these activities. Areas of the Big Hope Project analysis area not hosting salvage or roadside hazard tree removal operations will be open to seasonal firewood cutting, with activity areas opening after logging operations. Firewood would continue to be removed near forest system roads, resulting in a cumulative reduction of large fuels within the analysis area. Several commercial logging operations on private property within and near the analysis area are currently active. Approximately 5,000 acres, or nineteen percent of the American Fire area, burned on private land within the greater Tahoe National Forest. The California Department of Forestry has approved harvest plans for 3,168 acres, 62 percent of the private land and eleven percent of the overall burned area in It is unlikely any additional salvage logging will occur on private land, due to topographical constraints and the necessity for expedience when harvesting dead or dying trees. The apparent management strategy for these areas is timber salvage, with rapid reforestation for commercial timber production as a long term goal. Sub merchantable timber and woody debris is being piled and burned on these projects, greatly reducing surface fuel loads. These treatments are expected to positively influence wildfire behavior within and outside of the logged areas. Cumulative Effects Summary for Alternative 1 19

20 The 2013 American Fire dramatically reduced surface fine fuel loads, old deep duff and litter layers, and ladder fuel continuity across a wide area. The Big Hope project, combined with past, present and reasonably foreseeable future actions described above, would have minor cumulative effects on existing and future wildfire characteristics and potentially significant positive cumulative effects on wildfire control operations within the Big Hope analysis area. Alternative 2, No Action Direct and Indirect Effects Analysis Under this alternative, no treatments would occur in any areas. The charts illustrating surface fuel loading, amounts of standing snags, and flame lengths in high vegetation burn severity and low/moderate vegetation burn severity presented for Alternative 1 in the preceding sections also display effects for Alternative 2 (displayed as existing condition in the charts). Under Alternative 2, many historically forested areas would not return for decades, replaced by dense shrub and brush fields. Surface and ladder fuels will reestablish and begin to accumulate. Initially, lack of fuels in the burned area generally will not support large high intensity wildfires. As fire killed vegetation falls into a growing volume of live vegetation, wildfires may be expected to grow in intensity, size and suppression difficulty, and the trend of increasing stand replacing wildfire, with associated ecosystem impacts, will not change (Miller et al 2008). Because the Tahoe National Forest Fire Management Plan (TNF FMP) requires all wildfires be fully controlled as soon as possible, naturally occurring low intensity fires will be extinguished upon discovery. As wildfire intensities or a high volume of standing dead trees preclude direct suppression with ground forces, indirect tactics, heavy equipment and aircraft would be utilized. Burned areas and suppression and emergency rehabilitation costs would increase. Cumulative Effects Surface fuel loads will increase as grasses, shrubs and trees re-colonize the burned area and fire killed trees decay and fall. Fine dead surface fuel layers (the result of generations of plant life cycles) take much longer to regenerate. While the large dead standing and fallen snags influence future fire intensity and residence times (the duration of thermal impact of the fire on a specific area) in their immediate vicinity, they do not directly dictate overall fire behavior. Large dead snags primarily affect suppression efforts by posing an unacceptable level of risk to firefighters. Dead snags ignite easily from, and produce airborne firebrands which complicate control measures. Standing dead trees, burning or not, may fall without warning at any time and in any direction. Decayed trees may fall as a direct, unintentional result of typical fire suppression or other forest activities. Fallen trees block existing roads and trails, and may significantly reduce fuel break construction rates and compromise fire control lines. Existing and future projects are the same as those listed in the proposed action. The proposed action s objectives of reducing the danger and difficulty of managing future wildfires, reducing snag hazards, and reestablishing the fuel characteristics of resilient, fireadapted forests would not be met. While the beneficial impacts of other past, present, and reasonably foreseeable future actions on fire and fuels management would be realized under the no action alternative, long-term beneficial effects under the proposed action, particularly those related to opportunities for safe and efficient future fire suppression tactics and more rapidly re-establishing forested conditions, would not be realized. The cumulative effect 20