The University of San Francisco USF Scholarship: a digital repository @ Gleeson Library | Geschke Center Master's Projects and Capstones Theses, Dissertations, Capstones and Projects Spring 5-23-2020 The relationship between forest fires and forest dynamics in California’s North Coast Bioregion: How altered fire regimes have affected the vegetative outcomes of oak woodlands and mixed conifer forests Max Bencomo [email protected] Follow this and additional works at: https://repository.usfca.edu/capstone Part of the Forest Management Commons Recommended Citation Bencomo, Max, "The relationship between forest fires and forest dynamics in California’s North Coast Bioregion: How altered fire regimes have affected the vegetative outcomes of oak woodlands and mixed conifer forests" (2020). Master's Projects and Capstones. 1031. https://repository.usfca.edu/capstone/1031 This Project/Capstone is brought to you for free and open access by the Theses, Dissertations, Capstones and Projects at USF Scholarship: a digital repository @ Gleeson Library | Geschke Center. It has been accepted for inclusion in Master's Projects and Capstones by an authorized administrator of USF Scholarship: a digital repository @ Gleeson Library | Geschke Center. For more information, please contact [email protected]. This Master's Project The relationship between forest fires and forest dynamics in California’s North Coast Bioregion: How altered fire regimes have affected the vegetative outcomes of oak woodlands and mixed conifer forests by Max Bencomo is submitted in partial fulfillment of the requirements for the degree of: Master of Science in Environmental Management at the University of San Francisco Submitted: Received: ...................................……….. ................................…………. Max Bencomo Date Stephanie Siehr, Ph.D. Date TABLE OF CONTENTS TABLE OF CONTENTS ............................................................................................................................................... I LIST OF FIGURES ..................................................................................................................................................... II LIST OF TABLES ..................................................................................................................................................... III ABSTRACT ............................................................................................................................................................. IV 1. INTRODUCTION .............................................................................................................................................. 1 1.1 RESEARCH QUESTIONS ............................................................................................................................................... 4 1.2 METHODS ............................................................................................................................................................... 5 1.2.1 Case Study Analysis ....................................................................................................................................... 6 1.2.2 Comparative Analysis ................................................................................................................................... 7 1.2.3 SWOT Analysis .............................................................................................................................................. 8 1.2.4 Literature Review .......................................................................................................................................... 8 2. BACKGROUND ................................................................................................................................................ 9 2.1 DESIGNATION OF BIOREGION & CLIMATE .................................................................................................................... 10 2.2 HISTORY OF NORTHERN CALIFORNIA COASTAL WILDFIRES .............................................................................................. 12 2.3 ECOREGIONS OF STUDY: OAK WOODLANDS AND MIXED CONIFER FORESTS ........................................................................ 13 3. FIRES AND FORESTS...................................................................................................................................... 15 3.1 FIRE REGIMES ........................................................................................................................................................ 15 3.2 FIRE ADAPTATIONS IN BIOREGIONS............................................................................................................................. 21 4. FIRE AND INVASIVE SPECIES ......................................................................................................................... 22 5. FINDINGS ON FORESTS, FIRES, AND INVASIVES ............................................................................................ 25 5.1 INVASIVE INFLUENCES .............................................................................................................................................. 26 5.1.1 Mixed Conifer Forests ................................................................................................................................. 26 5.1.2 Oak Woodlands........................................................................................................................................... 30 5.1.3 Does Fire Regime Change Lead to Greater Invasive Populations? .............................................................. 32 5.2 CONFLICTED CONIFERS ............................................................................................................................................. 34 5.3 ENCROACHED OAKS ................................................................................................................................................ 40 6. MANAGEMENT FINDINGS AND RECOMMENDATIONS ................................................................................. 47 6.1 INVASIVE MANAGEMENT METHODS ........................................................................................................................... 47 6.1.1 Mastication ................................................................................................................................................. 47 6.1.2 Prescribed Burning ...................................................................................................................................... 52 6.2 MANAGEMENT OF MIXED CONIFER FORESTS................................................................................................................ 57 6.3 MANAGEMENT OF OAK WOODLANDS ......................................................................................................................... 60 7. CONCLUSIONS .............................................................................................................................................. 64 8. REFERENCES ................................................................................................................................................. 67 i LIST OF FIGURES Figure 1: Research Methods (Author) Figure 2: Map of California Ecological Zones. Taken from Fire in California Ecosystems (Van Wagtendonk et al., 2018) Figure 3: Figure 3: California Biomes (AP Environmental Science) (https://civilizedape.weebly.com/biomes-of-california.html) Figure 4: Visual key of common oak species within North Coast bioregion. (CNPS, 2019) Figure 5: Examples of conifer needles. (https://www.growforagecookferment.com/foraging-for- pine-needles/) Figure 5: Description of Heinselman’s Fire Regimes. Sugihara et al., 2018 Figure 6: Assessment of fire severity. (Welch et al., 2015) Figure 7: Visual representation of grass-fire cycle. (D’Antonio and Vitousek, 1992) Figure 8: Diagram of Findings: 3 Impacts (Author) Figure 9: Recorded distribution and abundance counts of invasive species across both NRI and TNC plots. (Klinger et al., 2006) Figure 10: Representation of the mean coverage of invasive species in Yosemite National Park. (Klinger et al., 2006) Figure 11: The historic fire regimes (pre-Euro American settlement) of related forest types with emphasis on Fire Return Interval (FRI). Based upon CALVEG (Classification and Assessment with Landsat of Visible Ecological Groupings) (USDA, 2013) classification. (Welch et al., 2016) Figure 12: Abundance changes of plant groups after Cedar Fire in San Diego (Franklin et al., 2006) Figure 13: Common conifer species located in study sites. (Welch et al., 2016) Figure 14: The progression of mean and median conifer seedling densities as determined by fire severity. (Welch et al., 2016, Safford et al., 2012) Figure 15: Representation of how the lack of historic fire regime enhances conifer encroachment. (Cocking et al., 2012) ii Figure 16: The time expectancy for different stages of conifer encroachment to occur. (Cocking et al., 2015) Figure 17: The four stages of conifer encroachment (Cocking et al., 2015) Figure 18: Representation of the change in species dominance following the Chips Fire. (Nemens et al., 2018) Figure 19: Photos of mastication and the resultant material debris (mulch). (Wilkin et al., 2017) Figure 20: “SWOT” Analysis of Mastication methods (Author) Figure 21: Abundance of native and non-native grasses present following management efforts. (Potts and