Red Fir Ecosystems Climate Change Vulnerability, Adaptaon Strategies, and Management Implicaons General Informaon: In the Sierra Nevada, red fir forests extend near the northern California border southward to Kern County in the southern Sierras. Red fir (Abies magnifica) dominates large high elevaon areas (1829-2743 m; 6000-9000 ), preferring cool and moist climates with more precipitaon (especially in the form of snow) and soil moisture. Red fir forests are currently both within and outside their natural range of variaon, as their structure has shied with stand homogenizaon including increases in small and medium trees and decreases in large trees. Significant stressors for the red fir system include insects and pathogens, fire suppression pracces that have increased interspecific compeon, and moisture stress leading to increased mortality. Other component © Marcia Wright species include white fir (Abies concolor) and lodgepole pine (Pinus contorta).

Ecosystem Vulnerability: Moderate Red fir ecosystems occupy cool and wet microclimates. They are sensive Very Low Very High to any climate or climate-driven changes that warm or dry their habitat, including warmer air temperatures, reduced snowpack, reduced soil moisture, and altered fire regimes. A warmer and drier climate may restrict red fir forest habitat distribuon and/or alter species composion, increasing the dominance of lodgepole pine and drought-tolerant white fir while reducing the dominance of moisture-dependent red fir. Red fir ecosystems are also sensive to pathogens and insects, which can increase tree sensivity to drought and/or cause direct tree mortality. Projected Climate and Climate-Driven Impacts on Red Fir Ecosystems Changes Increased temperatures (+2.4 to +3.4˚C), • Increased potenal evaporaon with largest increases during summer • Altered establishment, distribuon, growth, and species composion (e.g., increased dominance of white fir, reduced dominance of red fir Snowpack changes: • Species composion shis (e.g., increased white fir dominance, • Decreased snowpack (-64% to -87%), reduced red fir dominance) especially in northern range • Earlier and prolonged dry season • Earlier snowmelt • Reduced soil moisture, which can affect species composion and system distribuon Increased climac water deficit by up to • Reduced soil moisture, which can affect species composion and 44%, especially in the northern range system distribuon Increased fire frequency and intensity • Long term effects are poorly understood: - Intense fires: Increased red fir mortality, retarded red fir seed producon, reduced system extent, shis in species composion - May create colonizaon opportunies for lodgepole pine Fragmented forest distribuon, limited space to migrate vercally, and Cooler areas with adequate soils, slow post-fire regeneraon increases the vulnerability of this system. Red firs are likely less resilient to climate changes than white fir and such as northern aspects and lodgepole pine. Red firs require cool, mesic condions; their dominance unoccupied uphill sites that retain within the system declines with rising temperatures, shiing freezing snowpack, could act as refugia sites levels, and reduced snowpack and soil moisture. for red fir ecosystems in the future Adaptaon Strategies for Red Fir Ecosystems Adaptaon Strategy Specific Management Acons Understand and promote • Develop an ecosystem management strategy specific to Sierra Nevada red fir fundamental ecological funcons forests by ulizing current science informaon from an interdisciplinary and processes of red fir perspecve (e.g., forest ecology, fire ecology, climate change). Consider using recruitment and growth North et al. 2009 and North 2012 as a guide. • Develop a large-scale, coordinated monitoring program (including “cizen science” groups) to detect and predict future changes in red fir ecosystems • Decrease soil moisture deficits by reducing stem density (while maintaining canopy cover) • Thin red fir stands sequenally and use prescribed fire when possible • Experiment with silvicultural techniques to see which achieve desired structure and composion Develop and maintain core • Maintain red fir ecosystems closer to their natural range of variaon using current and projected marten management techniques menoned above habitat areas and corridors

A landscape-level adapve management experiment tesng a variety of current management strategies (i.e., fire and thinning) could be used to beer understand what methods benefit the red fir system and improve tree recruitment

© USFWS © Dayene Oliveira

© Chris Jordan-Bloch

Management Implicaons This informaon can be used in a variety of ways: ✔ Forest Plan Revisions ✔ U.S. Forest Service Climate Change Performance Scorecard: Element 6 - “Assessing Vulnerability” and Element 7 - “Adaptaon Acons” ✔ Naonal Park Service Resource Stewardship Strategies, Fire and Fuel Management Plans, General Management Plans, Strategic Plans, and Wilderness Stewardship Plans

Further informaon and citaons can be found in source reports, A Climate Change Vulnerability Assessment for Focal Resources of the Sierra Nevada and Climate Change Adaptaon Strategies for Focal Resources of the Sierra Nevada, available online at the EcoAdapt Library: hp://ecoadapt.org/library.