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• 1. [Article] CEO 1 ; An Illustrated Guide to Fire in Central Oregon Forests

  This pictorial guide is primarily intended to serve as a backdrop for field tours of central Oregon that involve topics surrounding wildland fire. It also is designed to provide an overview of the role ...

  Citation × Citation Citation Abstract Copy Title: CEO 1 ; An Illustrated Guide to Fire in Central Oregon Forests Author: Tappeiner, J. C. (John C.), Eckert, Bradley E., Walstad, John D., Oregon State University. Forest Research Laboratory This pictorial guide is primarily intended to serve as a backdrop for field tours of central Oregon that involve topics surrounding wildland fire. It also is designed to provide an overview of the role of fire in the major ecosystems characteristic of this region. Topics covered include fire history, fire regimes, current fire conditions, fire behavior, fire threats to natural resources, fuel treatments, interactions with the public, and future challenges and management options. A list of key references and glossary are also included. Title: CEO 1 ; An Illustrated Guide to Fire in Central Oregon Forests Author: Tappeiner, J. C. (John C.), Eckert, Bradley E., Walstad, John D., Oregon State University. Forest Research Laboratory This pictorial guide is primarily intended to serve as a backdrop for field tours of central Oregon that involve topics surrounding wildland fire. It also is designed to provide an overview of the role of fire in the major ecosystems characteristic of this region. Topics covered include fire history, fire regimes, current fire conditions, fire behavior, fire threats to natural resources, fuel treatments, interactions with the public, and future challenges and management options. A list of key references and glossary are also included. Close

• 2. [Article] Vegetation response to prescribed fire in mountain big sagebrush ecosystems at Lava Beds National Monument, California

  Anthropogenic land use alterations such as livestock grazing and fire suppression have greatly altered sagebrush grasslands of the Great Basin, facilitating invasion of exotic annuals, increases in woody ...

  Citation × Citation Citation Abstract Copy Title: Vegetation response to prescribed fire in mountain big sagebrush ecosystems at Lava Beds National Monument, California Author: Ellsworth, Lisa M. Anthropogenic land use alterations such as livestock grazing and fire suppression have greatly altered sagebrush grasslands of the Great Basin, facilitating invasion of exotic annuals, increases in woody species, and losses of native species. Much of the current research surrounding wildland and prescribed fire in sagebrush dominated ecosystems has focused on a persistent belief that fire in sagebrush systems results in a loss of native flora and a trend toward dominance by exotic annuals. Fire was historically the dominant disturbance throughout the sagebrush steppe and the plant species that comprised these communities possess a variety of adaptations facilitating survival to the fire regime. In order to restore ecosystems, land managers will need to reintroduce natural ecosystem processes, including natural disturbance processes. To describe the response of these plant communities to fire, I examined the plant community response, seedbank response, and reproductive and density responses of three native bunchgrasses (Pseudoroegneria spicata, Achnatherum therberianum, and Elymus elymoides) as well as one native forb (Calochortus macrocarpus) following spring and fall prescribed fires at Lava Beds National Monument. Fires were applied to three Artemisia tridentata ssp. vaseyana (Mountain Big Sagebrush) plant communities with different land use and fire histories. These communities were different in composition ranging from a dominance of exotic annuals to dominance by native grasses, shrubs, and trees. Little is known about how prescribed fire affects the soil seed bank in sagebrush-dominated ecosystems. To address this, we quantified the emergence of Bromus tectorum (cheatgrass) seedlings as well as emergence of seedlings of functional groups (native forbs, bunchgrasses, and shrubs) in a seedbank germination study. At the invasive dominated site (Gillems Camp), we found 91% fewer B. tectorum seedlings germinated in spring burned sites than in controls immediately following spring prescribed burns. However, soils collected one-year following fire had 40% more B. tectorum germinants (8017 germinants/m [superscript 2]) than unburned controls (5132 germinants/m [superscript 2]). Following fall burns at this site there was a similar response, with a 56% immediate reduction in B. tectorum (as compared to unburned control) and a 59% increase in B. tectorum and 58% increase in exotic forb germinants one year following fires. There was an increase in native forb germination following spring burns (94%) and fall burns (45%) at a site dominated by native plants (Fleener Chimneys). Native bunchgrass seed germination declined following spring fire in sites dominated by sagebrush and native understory vegetation (79%), and in sites where Juniperus occidentalis (western juniper) and other woody species dominated (Merrill Caves) (71%). In invasive-dominated sites (Gillems Camp), there was a decrease in B. tectorum cover following both spring (81% decrease) and fall fires (82% decrease), and little native vegetation composition change. Shrub cover, made up predominantly of Chrysothamnus nauseosus, decreased following spring (95% decrease) and fall (93% decrease) fires. At the sagebrush, native understory site (Fleener Chimneys), there was a reduction in native bunchgrass cover (64% decrease), and an increase in native forbs (168% increase) following spring burns, with no changes following fall fires. At the juniper- woody dominated site (Merrill Caves), fire treatments resulted in a decrease in woody plant cover, with no immediate postfire differences seen in the herbaceous plant community. Density of bunchgrass species (Pseudoroegneria spicata, Achnatherum therberianum, Elymus elymoides) did not change following either spring or fall prescribed fire treatments. Fire enhanced flowering was not seen in C. macrocarpus following spring or fall burns at the native or juniper dominated sites. There was increased reproductive effort in native bunchgrass species following fires in all communities studied. Following spring fires at invasive dominated sites, there was a 245% increase in reproductive culms of P. spicata. Following fall fires in native dominated sites, we saw a 974% increase in reproductive culms of P. spicata and a 184% increase in reproductive culms of A. therberianum. Following fall fires at juniper-dominated sites, we saw in an increase in reproductive culms of P. spicata (678% increase), A. thurberianum (356% increase), and Elymus elymoides (209% increase). These results suggest that implementing prescribed fire in order to restore the natural disturbance regime in these fire-adapted ecosystems is beneficial to restoration and preservation of the native biota. Title: Vegetation response to prescribed fire in mountain big sagebrush ecosystems at Lava Beds National Monument, California Author: Ellsworth, Lisa M. Anthropogenic land use alterations such as livestock grazing and fire suppression have greatly altered sagebrush grasslands of the Great Basin, facilitating invasion of exotic annuals, increases in woody species, and losses of native species. Much of the current research surrounding wildland and prescribed fire in sagebrush dominated ecosystems has focused on a persistent belief that fire in sagebrush systems results in a loss of native flora and a trend toward dominance by exotic annuals. Fire was historically the dominant disturbance throughout the sagebrush steppe and the plant species that comprised these communities possess a variety of adaptations facilitating survival to the fire regime. In order to restore ecosystems, land managers will need to reintroduce natural ecosystem processes, including natural disturbance processes. To describe the response of these plant communities to fire, I examined the plant community response, seedbank response, and reproductive and density responses of three native bunchgrasses (Pseudoroegneria spicata, Achnatherum therberianum, and Elymus elymoides) as well as one native forb (Calochortus macrocarpus) following spring and fall prescribed fires at Lava Beds National Monument. Fires were applied to three Artemisia tridentata ssp. vaseyana (Mountain Big Sagebrush) plant communities with different land use and fire histories. These communities were different in composition ranging from a dominance of exotic annuals to dominance by native grasses, shrubs, and trees. Little is known about how prescribed fire affects the soil seed bank in sagebrush-dominated ecosystems. To address this, we quantified the emergence of Bromus tectorum (cheatgrass) seedlings as well as emergence of seedlings of functional groups (native forbs, bunchgrasses, and shrubs) in a seedbank germination study. At the invasive dominated site (Gillems Camp), we found 91% fewer B. tectorum seedlings germinated in spring burned sites than in controls immediately following spring prescribed burns. However, soils collected one-year following fire had 40% more B. tectorum germinants (8017 germinants/m [superscript 2]) than unburned controls (5132 germinants/m [superscript 2]). Following fall burns at this site there was a similar response, with a 56% immediate reduction in B. tectorum (as compared to unburned control) and a 59% increase in B. tectorum and 58% increase in exotic forb germinants one year following fires. There was an increase in native forb germination following spring burns (94%) and fall burns (45%) at a site dominated by native plants (Fleener Chimneys). Native bunchgrass seed germination declined following spring fire in sites dominated by sagebrush and native understory vegetation (79%), and in sites where Juniperus occidentalis (western juniper) and other woody species dominated (Merrill Caves) (71%). In invasive-dominated sites (Gillems Camp), there was a decrease in B. tectorum cover following both spring (81% decrease) and fall fires (82% decrease), and little native vegetation composition change. Shrub cover, made up predominantly of Chrysothamnus nauseosus, decreased following spring (95% decrease) and fall (93% decrease) fires. At the sagebrush, native understory site (Fleener Chimneys), there was a reduction in native bunchgrass cover (64% decrease), and an increase in native forbs (168% increase) following spring burns, with no changes following fall fires. At the juniper- woody dominated site (Merrill Caves), fire treatments resulted in a decrease in woody plant cover, with no immediate postfire differences seen in the herbaceous plant community. Density of bunchgrass species (Pseudoroegneria spicata, Achnatherum therberianum, Elymus elymoides) did not change following either spring or fall prescribed fire treatments. Fire enhanced flowering was not seen in C. macrocarpus following spring or fall burns at the native or juniper dominated sites. There was increased reproductive effort in native bunchgrass species following fires in all communities studied. Following spring fires at invasive dominated sites, there was a 245% increase in reproductive culms of P. spicata. Following fall fires in native dominated sites, we saw a 974% increase in reproductive culms of P. spicata and a 184% increase in reproductive culms of A. therberianum. Following fall fires at juniper-dominated sites, we saw in an increase in reproductive culms of P. spicata (678% increase), A. thurberianum (356% increase), and Elymus elymoides (209% increase). These results suggest that implementing prescribed fire in order to restore the natural disturbance regime in these fire-adapted ecosystems is beneficial to restoration and preservation of the native biota. Close

• 3. [Article] Mixed-Severity Fire Effects on Biological Legacies and Vegetation Response in Pseudotsuga Forests of Western Oregon's Central Cascades, USA

  Mixed-severity fire occurrence is increasingly recognized in Pseudotsuga forests of the Pacific Northwest, but questions remain about how tree mortality varies, and forest structure is altered, across ...

  Citation × Citation Citation Abstract Copy Title: Mixed-Severity Fire Effects on Biological Legacies and Vegetation Response in Pseudotsuga Forests of Western Oregon's Central Cascades, USA Author: Dunn, Christopher J. Mixed-severity fire occurrence is increasingly recognized in Pseudotsuga forests of the Pacific Northwest, but questions remain about how tree mortality varies, and forest structure is altered, across the disturbance gradient observed in these fires. Therefore, we sampled live and dead biological legacies at 45 one ha plots, with four 0.10 ha nested plots, stratified across an unburned, low, moderate and high-severity fire gradient. We used severity estimates based on differenced Normalized Burn Ratio (dNBR), and captured a disturbance gradient, but plots in our low-severity class underestimated fire effects because of misclassification or delayed mortality. We estimated probability of mortality for shade-intolerant (Douglas-fir, incense-cedar, sugar pine) and shade-tolerant (western hemlock, western redcedar, true fir) trees from 5,079 sampled trees and snags. The probability of mortality was higher for shade-tolerant species across all fire-severity classes, and decreased with increasing DBH except for western hemlock. Only large, shade-intolerant trees survived high-severity fire. Post-fire snag fall and fragmentation were estimated from 2,746 sampled snags and logs. The probability of snag fall decreased with increasing DBH for all species, and was positively correlated with fire severity, except for Douglas-fir that had a higher probability following low-severity fire. Snag fragmentation was positively correlated with DBH and fire severity for all species. We also estimated the coefficient of variation within- and among-plots by fire severity class, as well as across all sampled conditions. Structural attributes varied more within- than among-plots, likely a result of increasing sub-hectare patchy mortality as fire intensity increased. Although vertical and horizontal structural diversity increased at sub-hectare scales, the coefficient of variation was highest for all structural attributes when compared across all fire severity classes. Therefore, the range of fire effects observed in mixed-severity fires may be functionally important in creating structural complexity across landscapes, which is an important attribute of old-growth forests in the Pacific Northwest. Understory vegetation response to mixed-severity fires has not been characterized for these forests even though the majority of vegetation diversity is found in these vegetation layers. Therefore, we sampled forest structure (1000 m² circular plots) and understory vegetation (100 m² plots) at 168 collocated plots stratified across unburned, low, moderate and high-severity conditions 10 years (Tiller Complex) and 22 years (Warner Fire) post-fire. We focused on shrub species, but sampled forbs, graminoids, ferns and moss as functional groups. Offsite colonization and fire stimulated soil seedbanks increased the total species richness from 23 to 46. The life-history strategies of residual and colonizing species resulted in three dominant species response-curves to the magnitude of disturbance: 1) 'disturbance-sensitive', when relative abundance was highest in unburned plots and continued to decline with increasing fire severity, 2) 'disturbance-stimulated', when relative abundance was highest following low or moderate-severity fire and 3) 'disturbance-amplified', when relative abundance increased with increasing fire severity. Residual and colonizing species assemblages promoted five or six distinct understory communities, dominantly driven by legacy tree basal area rather than the proportion of basal area killed. Understory communities were rarely associated with one disturbance severity class as fire refugia, variation in overstory and understory fire severity, and compensatory conditions offset fire effects. Early-seral habitats were the most different from unburned forests, but were not the only post-fire conditions important across these burned landscapes. Interactions among live and dead forest structures following low or moderate-severity fire, and the vegetation response to these conditions, are also unique to the post-fire landscape and likely important for various wildlife species. Therefore, if ecological forestry paradigms focus dominantly on creating old-growth structure or early-seral habitats, they might exclude important conditions that contribute to the landscape structural complexity created by mixed-severity fires. Additionally, tree regeneration response to mixed-severity fires has not been characterized for these forests even though they offer insight into one aspect of the resilience of these ecosystems to disturbance. Therefore, we sampled forest structure (1000 m² circular plots) and regeneration dynamics (100 m² plots) at 168 collocated plots stratified across unburned, low, moderate and high-severity conditions 10 years (Tiller Complex) and 22 years (Warner Fire) post-fire. The largest marginal increase in tree mortality (stems ha⁻¹) occurred between unburned and low-severity fires, given preferential mortality of small trees and shade-tolerant species, but basal area mortality had the largest marginal increase moving from moderate to high-severity. Pairwise comparisons of legacy tree basal area between low and moderate-severity weren’t as significant as other comparisons, but did capture a gradient of increasing fire effects. Quadratic mean diameter and canopy base height were positively correlated with fire severity as incrementally larger trees were killed and canopy ascension followed. Regeneration density increased regardless of severity, relative to unburned forests (median density of 1,384 trees ha⁻¹), but the highest median density (16,220 trees ha⁻¹) followed low-severity fire at the Tiller Complex and moderate-severity fire (14,472 trees ha⁻¹) at Warner Fire. Plot-level average species richness was highest following these same fire severity classes, supporting the Intermediate Disturbance Hypothesis. Statistically distinct regeneration communities occurred across the fire severity gradient at both fire sites. The relative abundance of shade-tolerant tree species decreased as fire severity increased, except for a divergent response following stand-initiation at the Warner Fire. While divergent successional pathways were evident within a couple decades following stand-initiation, low or moderate-severity fires also modified successional trajectories and may be the most functionally important disturbance magnitude because it has the greatest potential to increase compositional and structural diversity. Incorporating mixed-severity fire effects into landscape management of Pseudotsuga forests could increase structural complexity at stand and landscape-scales. Title: Mixed-Severity Fire Effects on Biological Legacies and Vegetation Response in Pseudotsuga Forests of Western Oregon's Central Cascades, USA Author: Dunn, Christopher J. Mixed-severity fire occurrence is increasingly recognized in Pseudotsuga forests of the Pacific Northwest, but questions remain about how tree mortality varies, and forest structure is altered, across the disturbance gradient observed in these fires. Therefore, we sampled live and dead biological legacies at 45 one ha plots, with four 0.10 ha nested plots, stratified across an unburned, low, moderate and high-severity fire gradient. We used severity estimates based on differenced Normalized Burn Ratio (dNBR), and captured a disturbance gradient, but plots in our low-severity class underestimated fire effects because of misclassification or delayed mortality. We estimated probability of mortality for shade-intolerant (Douglas-fir, incense-cedar, sugar pine) and shade-tolerant (western hemlock, western redcedar, true fir) trees from 5,079 sampled trees and snags. The probability of mortality was higher for shade-tolerant species across all fire-severity classes, and decreased with increasing DBH except for western hemlock. Only large, shade-intolerant trees survived high-severity fire. Post-fire snag fall and fragmentation were estimated from 2,746 sampled snags and logs. The probability of snag fall decreased with increasing DBH for all species, and was positively correlated with fire severity, except for Douglas-fir that had a higher probability following low-severity fire. Snag fragmentation was positively correlated with DBH and fire severity for all species. We also estimated the coefficient of variation within- and among-plots by fire severity class, as well as across all sampled conditions. Structural attributes varied more within- than among-plots, likely a result of increasing sub-hectare patchy mortality as fire intensity increased. Although vertical and horizontal structural diversity increased at sub-hectare scales, the coefficient of variation was highest for all structural attributes when compared across all fire severity classes. Therefore, the range of fire effects observed in mixed-severity fires may be functionally important in creating structural complexity across landscapes, which is an important attribute of old-growth forests in the Pacific Northwest. Understory vegetation response to mixed-severity fires has not been characterized for these forests even though the majority of vegetation diversity is found in these vegetation layers. Therefore, we sampled forest structure (1000 m² circular plots) and understory vegetation (100 m² plots) at 168 collocated plots stratified across unburned, low, moderate and high-severity conditions 10 years (Tiller Complex) and 22 years (Warner Fire) post-fire. We focused on shrub species, but sampled forbs, graminoids, ferns and moss as functional groups. Offsite colonization and fire stimulated soil seedbanks increased the total species richness from 23 to 46. The life-history strategies of residual and colonizing species resulted in three dominant species response-curves to the magnitude of disturbance: 1) 'disturbance-sensitive', when relative abundance was highest in unburned plots and continued to decline with increasing fire severity, 2) 'disturbance-stimulated', when relative abundance was highest following low or moderate-severity fire and 3) 'disturbance-amplified', when relative abundance increased with increasing fire severity. Residual and colonizing species assemblages promoted five or six distinct understory communities, dominantly driven by legacy tree basal area rather than the proportion of basal area killed. Understory communities were rarely associated with one disturbance severity class as fire refugia, variation in overstory and understory fire severity, and compensatory conditions offset fire effects. Early-seral habitats were the most different from unburned forests, but were not the only post-fire conditions important across these burned landscapes. Interactions among live and dead forest structures following low or moderate-severity fire, and the vegetation response to these conditions, are also unique to the post-fire landscape and likely important for various wildlife species. Therefore, if ecological forestry paradigms focus dominantly on creating old-growth structure or early-seral habitats, they might exclude important conditions that contribute to the landscape structural complexity created by mixed-severity fires. Additionally, tree regeneration response to mixed-severity fires has not been characterized for these forests even though they offer insight into one aspect of the resilience of these ecosystems to disturbance. Therefore, we sampled forest structure (1000 m² circular plots) and regeneration dynamics (100 m² plots) at 168 collocated plots stratified across unburned, low, moderate and high-severity conditions 10 years (Tiller Complex) and 22 years (Warner Fire) post-fire. The largest marginal increase in tree mortality (stems ha⁻¹) occurred between unburned and low-severity fires, given preferential mortality of small trees and shade-tolerant species, but basal area mortality had the largest marginal increase moving from moderate to high-severity. Pairwise comparisons of legacy tree basal area between low and moderate-severity weren’t as significant as other comparisons, but did capture a gradient of increasing fire effects. Quadratic mean diameter and canopy base height were positively correlated with fire severity as incrementally larger trees were killed and canopy ascension followed. Regeneration density increased regardless of severity, relative to unburned forests (median density of 1,384 trees ha⁻¹), but the highest median density (16,220 trees ha⁻¹) followed low-severity fire at the Tiller Complex and moderate-severity fire (14,472 trees ha⁻¹) at Warner Fire. Plot-level average species richness was highest following these same fire severity classes, supporting the Intermediate Disturbance Hypothesis. Statistically distinct regeneration communities occurred across the fire severity gradient at both fire sites. The relative abundance of shade-tolerant tree species decreased as fire severity increased, except for a divergent response following stand-initiation at the Warner Fire. While divergent successional pathways were evident within a couple decades following stand-initiation, low or moderate-severity fires also modified successional trajectories and may be the most functionally important disturbance magnitude because it has the greatest potential to increase compositional and structural diversity. Incorporating mixed-severity fire effects into landscape management of Pseudotsuga forests could increase structural complexity at stand and landscape-scales. Close

• 4. [Article] The effects of natural fire and recreational disturbance on montane forest ecosystem composition, structure and nitrogen dynamics, Crater Lake National Park, Oregon

  Disturbance, whether natural or of human origin, modifies to varying degrees many ecosystem attributes. Fire is a natural process in the montane forests of southern Oregon but for much of the 20th century ...

  Citation × Citation Citation Abstract Copy Title: The effects of natural fire and recreational disturbance on montane forest ecosystem composition, structure and nitrogen dynamics, Crater Lake National Park, Oregon Author: Wilson, John K. (John Kevin) Disturbance, whether natural or of human origin, modifies to varying degrees many ecosystem attributes. Fire is a natural process in the montane forests of southern Oregon but for much of the 20th century fire was viewed as an apocalypse and thus fervently suppressed. Effective natural resource management requires an understanding of how ecosystems function, including the ecological response to the natural disturbance regime or anthropogenically altered conditions. To describe the effects of natural fire and ecosystem changes with time following fire, I examined plant composition, structure, biomass and soil nitrogen using a chronosequence of sites ranging in age from 1 to >300 years. The ecological importance of human activity is a function of the magnitude and permanence of its effects which were described at active and abandoned recreation sites. Stand-replacing fires killed virtually 100% of the overstory trees, consumed 87% of the forest floor and resulted in a 27% loss in total aboveground biomass. A pulse of mineralized nitrogen was still apparent 2 years following fire. Two years following fire, little plant colonization was established. The availability of local seed sources, particularly seedbanking species, appears to have been an important determinant of the early-successional community composition. The developing community was dominated by nitrogen-fixing species which may play an important role in the post-fire nitrogen dynamics in these ecosystems. Conifer seedling densities measured 667 individuals/ha 8 years following fire and 1714 individuals/ha 24 years after fire. Extended tree maturation and variation in composition characterized the forest structure and composition during secondary succession. Total aboveground biomass remained high and accumulation followed a general U-shaped curve. Recreational use resulted in a reduction in tree density and biomass at all active sites. The greatest reductions occurred at sites set in late-successional forests. Compositional change was also greatest at sites established in late-successional forest with increased dominance of lodgepole pine and graminoids. Within 40 years the abandoned, mid-successional sites had recovered from most of the recreational impacts; however 40 years was not sufficient for late-successional forest recovery. These results suggest that the stage of succession should be considered when assessing potential recreational impacts. Title: The effects of natural fire and recreational disturbance on montane forest ecosystem composition, structure and nitrogen dynamics, Crater Lake National Park, Oregon Author: Wilson, John K. (John Kevin) Disturbance, whether natural or of human origin, modifies to varying degrees many ecosystem attributes. Fire is a natural process in the montane forests of southern Oregon but for much of the 20th century fire was viewed as an apocalypse and thus fervently suppressed. Effective natural resource management requires an understanding of how ecosystems function, including the ecological response to the natural disturbance regime or anthropogenically altered conditions. To describe the effects of natural fire and ecosystem changes with time following fire, I examined plant composition, structure, biomass and soil nitrogen using a chronosequence of sites ranging in age from 1 to >300 years. The ecological importance of human activity is a function of the magnitude and permanence of its effects which were described at active and abandoned recreation sites. Stand-replacing fires killed virtually 100% of the overstory trees, consumed 87% of the forest floor and resulted in a 27% loss in total aboveground biomass. A pulse of mineralized nitrogen was still apparent 2 years following fire. Two years following fire, little plant colonization was established. The availability of local seed sources, particularly seedbanking species, appears to have been an important determinant of the early-successional community composition. The developing community was dominated by nitrogen-fixing species which may play an important role in the post-fire nitrogen dynamics in these ecosystems. Conifer seedling densities measured 667 individuals/ha 8 years following fire and 1714 individuals/ha 24 years after fire. Extended tree maturation and variation in composition characterized the forest structure and composition during secondary succession. Total aboveground biomass remained high and accumulation followed a general U-shaped curve. Recreational use resulted in a reduction in tree density and biomass at all active sites. The greatest reductions occurred at sites set in late-successional forests. Compositional change was also greatest at sites established in late-successional forest with increased dominance of lodgepole pine and graminoids. Within 40 years the abandoned, mid-successional sites had recovered from most of the recreational impacts; however 40 years was not sufficient for late-successional forest recovery. These results suggest that the stage of succession should be considered when assessing potential recreational impacts. Close

• 5. [Article] Age structure, developmental pathways, and fire regime characterization of Douglas-fir/western hemlock forests in the central western Cascades of Oregon

  Descriptions of the fire regime in the Douglas-fir/western hemlock region of the Pacific Northwest traditionally have emphasized infrequent, predominantly stand-replacement fires and an associated linear ...

  Citation × Citation Citation Abstract Copy Title: Age structure, developmental pathways, and fire regime characterization of Douglas-fir/western hemlock forests in the central western Cascades of Oregon Author: Tepley, Alan J. Descriptions of the fire regime in the Douglas-fir/western hemlock region of the Pacific Northwest traditionally have emphasized infrequent, predominantly stand-replacement fires and an associated linear pathway of stand development, where all stands proceed along a common pathway until reset by the next fire. Although such a description may apply in wetter parts of the region, recent fire-history research suggests drier parts of the region support a mixed-severity regime, where most fires have substantial representation of all severity classes and most stands experience at least one non-stand-replacing fire between stand-replacement events. This study combines field and modeling approaches to better understand the complex fire regime in the central western Cascades of Oregon. Stand-structure data and ages of more than 3,000 trees were collected at 124 stands throughout two study areas with physiography representative of western and eastern portions of the western Cascade Range. Major objectives were to (1) develop a conceptual model of fire-mediated pathways of stand development, (2) determine the strengths of influences of topography on spatial variation in the fire regime, (3) provide a stronger understanding of modeling approaches commonly used to gain insight into historical landscape structure, and (4) develop methods to predict trajectories of change in landscape age structure under a non-stationary fire regime. In the study area, non-stand-replacing fire interspersed with infrequent, stand-replacement events led to a variety of even-aged and multi-cohort stands. The majority of stands (75%) had two or more age cohorts, where post-fire cohorts were dominated either by shade-intolerant species or shade-tolerant species, depending largely on fire severity. Age structure, used as a proxy for the cumulative effects of fire on stand development, showed a moderately strong relationship to topography overall, but relationships were strongest at both extremes of a continuum of the influences of fire frequency and severity on stand development and relatively weak in the middle. High topographic relief in the eastern part of the western Cascades may amplify variation in microclimate and fuel moisture, leading to a finer-scale spatial variation in fire spread and behavior, and thus a broader range of stand age structures and stronger fidelity of age structure to slope position and terrain shape in the deeply dissected terrain of the eastern part of the western Cascades than in the gentler terrain of the western part. In the modeling component of my research, I was able to use analytical procedures to reproduce much of the output provided by a stochastic, spatial simulation model previously applied to evaluate historical landscape structure of the Oregon Coast Range. The analytical approximation provides an explicit representation of the effects of input parameters and interactions among them. The increased transparency of model function given by such an analysis may facilitate communication of model output and uncertainty among ecologists and forest managers. Analytical modeling approaches were expanded to characterize trajectories of change in forest age structure in response to changes in the fire regime. Following a change in fire frequency, the proportion of the landscape covered by stands of a given age class is expected to change along a non-monotonic trajectory rather than transition directly to its equilibrium abundance under the new regime. Under some scenarios of change in fire frequency, the time for the expected age distribution of a landscape to converge to the equilibrium distribution of the new regime can be determined based only on the magnitude of change in fire frequency, regardless of the initial value or the direction of change. The theoretical modeling exercises provide insight into historical trends in the study area. Compiled across all sample sites, the age distribution of Douglas-fir trees was strongly bimodal. Peaks of establishment dates in the 16th and 19th centuries were synchronous between the two study areas, and each peak of Douglas-fir establishment coincides with one of the two periods of region-wide extensive fire identified in a previous synthesis of fire-history studies. The modeling exercises support the development of such a bimodal age distribution in response to centennial-scale changes in fire frequency, and they illustrate how the relative abundance of different stand-structure types may have varied over the last several centuries. Title: Age structure, developmental pathways, and fire regime characterization of Douglas-fir/western hemlock forests in the central western Cascades of Oregon Author: Tepley, Alan J. Descriptions of the fire regime in the Douglas-fir/western hemlock region of the Pacific Northwest traditionally have emphasized infrequent, predominantly stand-replacement fires and an associated linear pathway of stand development, where all stands proceed along a common pathway until reset by the next fire. Although such a description may apply in wetter parts of the region, recent fire-history research suggests drier parts of the region support a mixed-severity regime, where most fires have substantial representation of all severity classes and most stands experience at least one non-stand-replacing fire between stand-replacement events. This study combines field and modeling approaches to better understand the complex fire regime in the central western Cascades of Oregon. Stand-structure data and ages of more than 3,000 trees were collected at 124 stands throughout two study areas with physiography representative of western and eastern portions of the western Cascade Range. Major objectives were to (1) develop a conceptual model of fire-mediated pathways of stand development, (2) determine the strengths of influences of topography on spatial variation in the fire regime, (3) provide a stronger understanding of modeling approaches commonly used to gain insight into historical landscape structure, and (4) develop methods to predict trajectories of change in landscape age structure under a non-stationary fire regime. In the study area, non-stand-replacing fire interspersed with infrequent, stand-replacement events led to a variety of even-aged and multi-cohort stands. The majority of stands (75%) had two or more age cohorts, where post-fire cohorts were dominated either by shade-intolerant species or shade-tolerant species, depending largely on fire severity. Age structure, used as a proxy for the cumulative effects of fire on stand development, showed a moderately strong relationship to topography overall, but relationships were strongest at both extremes of a continuum of the influences of fire frequency and severity on stand development and relatively weak in the middle. High topographic relief in the eastern part of the western Cascades may amplify variation in microclimate and fuel moisture, leading to a finer-scale spatial variation in fire spread and behavior, and thus a broader range of stand age structures and stronger fidelity of age structure to slope position and terrain shape in the deeply dissected terrain of the eastern part of the western Cascades than in the gentler terrain of the western part. In the modeling component of my research, I was able to use analytical procedures to reproduce much of the output provided by a stochastic, spatial simulation model previously applied to evaluate historical landscape structure of the Oregon Coast Range. The analytical approximation provides an explicit representation of the effects of input parameters and interactions among them. The increased transparency of model function given by such an analysis may facilitate communication of model output and uncertainty among ecologists and forest managers. Analytical modeling approaches were expanded to characterize trajectories of change in forest age structure in response to changes in the fire regime. Following a change in fire frequency, the proportion of the landscape covered by stands of a given age class is expected to change along a non-monotonic trajectory rather than transition directly to its equilibrium abundance under the new regime. Under some scenarios of change in fire frequency, the time for the expected age distribution of a landscape to converge to the equilibrium distribution of the new regime can be determined based only on the magnitude of change in fire frequency, regardless of the initial value or the direction of change. The theoretical modeling exercises provide insight into historical trends in the study area. Compiled across all sample sites, the age distribution of Douglas-fir trees was strongly bimodal. Peaks of establishment dates in the 16th and 19th centuries were synchronous between the two study areas, and each peak of Douglas-fir establishment coincides with one of the two periods of region-wide extensive fire identified in a previous synthesis of fire-history studies. The modeling exercises support the development of such a bimodal age distribution in response to centennial-scale changes in fire frequency, and they illustrate how the relative abundance of different stand-structure types may have varied over the last several centuries. Close

• 6. [Article] Dead fuels and understory vegetation six years after a large mixed-severity wildfire in southwest Oregon

  Though the mixed-evergreen forests of the Klamath Siskiyous have a long history of large, mixed-severity fires, most research in this region has concentrated on the impacts of high-severity fire. Knowledge ...

  Citation × Citation Citation Abstract Copy Title: Dead fuels and understory vegetation six years after a large mixed-severity wildfire in southwest Oregon Author: Nathanson, Amy Though the mixed-evergreen forests of the Klamath Siskiyous have a long history of large, mixed-severity fires, most research in this region has concentrated on the impacts of high-severity fire. Knowledge of the ecological effects of low- and moderate-severity areas within mixed-severity fires is important because such areas may account for over half the landscape affected by a fire. The purpose of this study was to understand the relationship of fire severity with dead fuels and understory vegetation across a full range of fire severities. Study sites were located within and just outside the boundary of the 2002 Biscuit Fire, which burned 200,000 hectares in a mosaic of burn severities. Six years after the Biscuit Fire, the biomass and depth of litter and duff was lower on burned sites than unburned sites, and lowest on high-severity sites. This relationship was reversed for woody fuels >7.62 cm in diameter, where quantities were highest in high- and extreme-severity areas, though there was no evidence that quantities differed between low-severity and unburned sites. There was no evidence of a relationship between woody fuels 0.64-7.62 cm in diameter and fire severity, 6 years post-fire. There was no evidence that fuel quantities differed between sites that burned only in the Biscuit Fire with sites that also burned 15 years earlier in the 1987 Silver Fire. Fuel quantities and composition differed between burned and unburned sites, but these differences disappeared if litter and duff were not considered. Fuel classes were correlated with each other within three general size classes: small (litter, duff, and fuels <2.54 cm), medium (fuels 2.54-30 cm), and large (fuels >30 cm). There was little correlation between these size classes. Vegetation response also varied by fire severity, species, and height. Generally, density for tree seedlings <0.5 m was highest on low-severity sites and lowest on high-severity sites. For seedlings 0.5-1.37 m the relationship was reversed, with the highest seedling densities in high-severity areas. Specific seedling relationships to burn severity and other explanatory factors (e.g. shrub cover, elevation, precipitation, maxiumun August temperatures) varied by species and seedling height. Average seedling densities were above the minimum acceptable stocking levels of 333 trees per hectare (135 seedlings/acre) as identified in federal plans for the fire area. Shrub species richness and diversity did not vary with burn severity; however, shrub species and ground cover composition did differ with burn severity six years after the Biscuit Fire. The relationship of understory cover composition with burn severity aligned with species life history traits; fire-adapted, nitrogen-fixing species were more prevalent on high- and extreme-severity sites while species associated with low-severity fire or old-growth forests were more prevalent on low-severity or unburned sites. I found no evidence of difference in total graminoid or forb cover based on fire severity, but shrub quantities were lower on low-severity sites than on unburned, high-, and extreme-severity sites. This study reveals how fuel and vegetation vary across the full range of fire severities. It demonstrates that mixed-severity fires create a mix of ecological responses. It also provides a baseline for future studies, as the relationships between fire severity and fuels or vegetation may disappear or change in subsequent decades. Title: Dead fuels and understory vegetation six years after a large mixed-severity wildfire in southwest Oregon Author: Nathanson, Amy Though the mixed-evergreen forests of the Klamath Siskiyous have a long history of large, mixed-severity fires, most research in this region has concentrated on the impacts of high-severity fire. Knowledge of the ecological effects of low- and moderate-severity areas within mixed-severity fires is important because such areas may account for over half the landscape affected by a fire. The purpose of this study was to understand the relationship of fire severity with dead fuels and understory vegetation across a full range of fire severities. Study sites were located within and just outside the boundary of the 2002 Biscuit Fire, which burned 200,000 hectares in a mosaic of burn severities. Six years after the Biscuit Fire, the biomass and depth of litter and duff was lower on burned sites than unburned sites, and lowest on high-severity sites. This relationship was reversed for woody fuels >7.62 cm in diameter, where quantities were highest in high- and extreme-severity areas, though there was no evidence that quantities differed between low-severity and unburned sites. There was no evidence of a relationship between woody fuels 0.64-7.62 cm in diameter and fire severity, 6 years post-fire. There was no evidence that fuel quantities differed between sites that burned only in the Biscuit Fire with sites that also burned 15 years earlier in the 1987 Silver Fire. Fuel quantities and composition differed between burned and unburned sites, but these differences disappeared if litter and duff were not considered. Fuel classes were correlated with each other within three general size classes: small (litter, duff, and fuels <2.54 cm), medium (fuels 2.54-30 cm), and large (fuels >30 cm). There was little correlation between these size classes. Vegetation response also varied by fire severity, species, and height. Generally, density for tree seedlings <0.5 m was highest on low-severity sites and lowest on high-severity sites. For seedlings 0.5-1.37 m the relationship was reversed, with the highest seedling densities in high-severity areas. Specific seedling relationships to burn severity and other explanatory factors (e.g. shrub cover, elevation, precipitation, maxiumun August temperatures) varied by species and seedling height. Average seedling densities were above the minimum acceptable stocking levels of 333 trees per hectare (135 seedlings/acre) as identified in federal plans for the fire area. Shrub species richness and diversity did not vary with burn severity; however, shrub species and ground cover composition did differ with burn severity six years after the Biscuit Fire. The relationship of understory cover composition with burn severity aligned with species life history traits; fire-adapted, nitrogen-fixing species were more prevalent on high- and extreme-severity sites while species associated with low-severity fire or old-growth forests were more prevalent on low-severity or unburned sites. I found no evidence of difference in total graminoid or forb cover based on fire severity, but shrub quantities were lower on low-severity sites than on unburned, high-, and extreme-severity sites. This study reveals how fuel and vegetation vary across the full range of fire severities. It demonstrates that mixed-severity fires create a mix of ecological responses. It also provides a baseline for future studies, as the relationships between fire severity and fuels or vegetation may disappear or change in subsequent decades. Close

• 7. [Article] The effects of forest fuel reduction on fire severity and long-term carbon storage

  Two forest management objectives being debated in the context of federally managed landscapes in the US Pacific Northwest involve a perceived trade-off between fire restoration and C sequestration. The ...

  Citation × Citation Citation Abstract Copy Title: The effects of forest fuel reduction on fire severity and long-term carbon storage Author: Mitchell, Stephen Richard Two forest management objectives being debated in the context of federally managed landscapes in the US Pacific Northwest involve a perceived trade-off between fire restoration and C sequestration. The former strategy would reduce fuel (and therefore C) that has accumulated through a century of fire suppression and exclusion that has led to extreme fire risk in some areas. The latter strategy would manage forests for enhanced C sequestration as a method of reducing atmospheric CO2 and associated threats from global climate change. We explored the tradeoff between these strategies by modeling their effects at both the stand and landscape-scale. We began with an assessment of the extent to which uncertainties in model parameter values, model structure, and field measurements can influence model performance. We adapted the generalized likelihood uncertainty estimation (GLUE) methodology for Biome-BGC, a widely used terrestrial ecosystem model. We found that the phenomenon of parameter equifinality exerted significant control on model performance, but that issues with model structure in the Biome-BGC model may present an even greater obstacle to model accuracy. We then examined the effects of fuel reduction on fire severity and the resulting long-term stand-level C storage by utilizing the STANDCARB model for three Pacific Northwest ecosystems: the east Cascades Ponderosa Pine forests, the west Cascades Western hemlock–Douglas fir forests, and the Coast Range Western hemlock– Sitka spruce forests. Finally, we then tested the extent to which various landscape-level fuel reduction treatments, when applied at various annual treatment areas, altered pyrogenic C emissions and long-term C storage in the east Cascades Ponderosa pine ecosystems. For this we employed the LANDCARB model, which models forests throughout a landscape on a stand-by-stand basis. Results from both the stand and landscape-level modeling indicate that, for fuel reduction treatments to be effective in reducing wildfire severity, they must be applied at higher frequencies and over larger areas than they are currently. Furthermore, fuel reduction treatments almost always reduce stand and landscape-level C storage, since reducing the fraction by which C is lost in a wildfire requires the removal of a much greater amount of C, since most of the C stored in forest biomass (stem wood, branches, coarse woody debris) remains unconsumed even by high-severity wildfires. Title: The effects of forest fuel reduction on fire severity and long-term carbon storage Author: Mitchell, Stephen Richard Two forest management objectives being debated in the context of federally managed landscapes in the US Pacific Northwest involve a perceived trade-off between fire restoration and C sequestration. The former strategy would reduce fuel (and therefore C) that has accumulated through a century of fire suppression and exclusion that has led to extreme fire risk in some areas. The latter strategy would manage forests for enhanced C sequestration as a method of reducing atmospheric CO2 and associated threats from global climate change. We explored the tradeoff between these strategies by modeling their effects at both the stand and landscape-scale. We began with an assessment of the extent to which uncertainties in model parameter values, model structure, and field measurements can influence model performance. We adapted the generalized likelihood uncertainty estimation (GLUE) methodology for Biome-BGC, a widely used terrestrial ecosystem model. We found that the phenomenon of parameter equifinality exerted significant control on model performance, but that issues with model structure in the Biome-BGC model may present an even greater obstacle to model accuracy. We then examined the effects of fuel reduction on fire severity and the resulting long-term stand-level C storage by utilizing the STANDCARB model for three Pacific Northwest ecosystems: the east Cascades Ponderosa Pine forests, the west Cascades Western hemlock–Douglas fir forests, and the Coast Range Western hemlock– Sitka spruce forests. Finally, we then tested the extent to which various landscape-level fuel reduction treatments, when applied at various annual treatment areas, altered pyrogenic C emissions and long-term C storage in the east Cascades Ponderosa pine ecosystems. For this we employed the LANDCARB model, which models forests throughout a landscape on a stand-by-stand basis. Results from both the stand and landscape-level modeling indicate that, for fuel reduction treatments to be effective in reducing wildfire severity, they must be applied at higher frequencies and over larger areas than they are currently. Furthermore, fuel reduction treatments almost always reduce stand and landscape-level C storage, since reducing the fraction by which C is lost in a wildfire requires the removal of a much greater amount of C, since most of the C stored in forest biomass (stem wood, branches, coarse woody debris) remains unconsumed even by high-severity wildfires. Close

• 8. [Article] The use of burned forest by breeding birds following the Biscuit Fire in southwest Oregon

  Fire severity is hypothesized as an important driver of bird responses to wildfire. For those species that typically respond negatively to increasing severity, Accessibility of high-severity burned forest ...

  Citation × Citation Citation Abstract Copy Title: The use of burned forest by breeding birds following the Biscuit Fire in southwest Oregon Author: Donaghy Cannon, Michelle M. Fire severity is hypothesized as an important driver of bird responses to wildfire. For those species that typically respond negatively to increasing severity, Accessibility of high-severity burned forest may be dependent on the proximity of unburned or low-severity burned forest to meet all of the needs of breeding bird species that typically respond negatively to increasing fire severity. We used dynamic occupancy modeling and intensive surveys to test the hypothesis that the presence of live trees explained distribution of birds in high-severity burned forest in the first three years following the Biscuit Complex Fire in southwest Oregon. Proximity of low-moderate severity burned forest appeared to be important for some foliage- and bark-gleaning species. However, probability of occurrence in high-severity patches for several canopy-associates was not associated with distance from low-moderate severity burned forest. We found strong evidence that large snags (>52-cm) and large live conifers provided important nest substrates for several of these open-cup nesting species. Sprouts from top-killed hardwood species provided primary nesting substrates for early-seral associates and some species that nest in live trees or mature shrubs in unburned forest. Large areas of high-severity burned forest appeared to provide important breeding habitat for edge-sensitive cavity-nesting species. Most cavity nests were in large fire-killed or legacy snags with significant decay. In all, bird species that were likely to nest in high-severity forest also were likely to persist in the early post-fire period. Identifying the structures used for nesting by these species provides a mechanistic understanding of the distributions of many species of breeding birds following wildfire, and underscores the importance of local ecological context in interpretation of the effects of disturbance. We used intensive surveys to evaluate the efficacy of point count surveys to detect breeding birds. Most species had significantly higher detection probabilities at sites with evidence of breeding activity than at sites without such evidence. Among species, however, detection probability did not predict prevalence of breeding. Most species for which detection probabilities during point counts were low or moderate were those predicted to decline following high-severity fire. This finding highlights the importance of evaluating detection probabilities to identify effective sampling methods for species expected to respond negatively to habitat alteration. Title: The use of burned forest by breeding birds following the Biscuit Fire in southwest Oregon Author: Donaghy Cannon, Michelle M. Fire severity is hypothesized as an important driver of bird responses to wildfire. For those species that typically respond negatively to increasing severity, Accessibility of high-severity burned forest may be dependent on the proximity of unburned or low-severity burned forest to meet all of the needs of breeding bird species that typically respond negatively to increasing fire severity. We used dynamic occupancy modeling and intensive surveys to test the hypothesis that the presence of live trees explained distribution of birds in high-severity burned forest in the first three years following the Biscuit Complex Fire in southwest Oregon. Proximity of low-moderate severity burned forest appeared to be important for some foliage- and bark-gleaning species. However, probability of occurrence in high-severity patches for several canopy-associates was not associated with distance from low-moderate severity burned forest. We found strong evidence that large snags (>52-cm) and large live conifers provided important nest substrates for several of these open-cup nesting species. Sprouts from top-killed hardwood species provided primary nesting substrates for early-seral associates and some species that nest in live trees or mature shrubs in unburned forest. Large areas of high-severity burned forest appeared to provide important breeding habitat for edge-sensitive cavity-nesting species. Most cavity nests were in large fire-killed or legacy snags with significant decay. In all, bird species that were likely to nest in high-severity forest also were likely to persist in the early post-fire period. Identifying the structures used for nesting by these species provides a mechanistic understanding of the distributions of many species of breeding birds following wildfire, and underscores the importance of local ecological context in interpretation of the effects of disturbance. We used intensive surveys to evaluate the efficacy of point count surveys to detect breeding birds. Most species had significantly higher detection probabilities at sites with evidence of breeding activity than at sites without such evidence. Among species, however, detection probability did not predict prevalence of breeding. Most species for which detection probabilities during point counts were low or moderate were those predicted to decline following high-severity fire. This finding highlights the importance of evaluating detection probabilities to identify effective sampling methods for species expected to respond negatively to habitat alteration. Close

• 9. [Article] Managing for landscape resilience in the frequent-fire forests of central Oregon

  Wildfire in dry, frequent-fire forests is a pressing issue for natural resource managers, communities and politicians in the western United States. Area affected by wildfire has climbed steadily over the last ...

  Citation × Citation Citation Abstract Copy Title: Managing for landscape resilience in the frequent-fire forests of central Oregon Author: Platt, Emily K. Wildfire in dry, frequent-fire forests is a pressing issue for natural resource managers, communities and politicians in the western United States. Area affected by wildfire has climbed steadily over the last twenty years and is expected to increase in the future. Recognition of the importance of both social and biophysical influences on wildfire management has led to calls for integrated social-ecological research and new methods for studying ecosystems that incorporate both social and biophysical science. This project integrates social and biophysical research methods to address research questions related to wildfire, forest dynamics, and management of national forestlands in Oregon's Central Cascades. Qualitative content analysis is paired with landscape modeling to answer research questions related to managing frequent-fire forests for landscape resilience. Collectively, both approaches present a more complete understanding of challenges and opportunities related to managing for landscape resilience than could either approach on its own. One common thread identified in both approaches is the importance of bringing more fire onto the landscape, either through the use of prescribed fire or carefully managed wildfire. Both interview respondents and modeling results demonstrate the importance of using managed fire to reduce the risk of high-severity wildfire. Another compelling result of the analysis stemmed from modeling simulations which showed current levels of management to lead to the same amount of high-severity fire as a no management scenario. Finally, the modeling results demonstrated that not every acre has to be managed to reduce wildfire risk across a larger landscape. Landscape-scale management plans are thus critical to the development of effective management strategies, and forest plans may fulfill this role. Forest Service budgeting based on forest plans could lead to more efficient, effective, and responsive public administration of federal lands. Title: Managing for landscape resilience in the frequent-fire forests of central Oregon Author: Platt, Emily K. Wildfire in dry, frequent-fire forests is a pressing issue for natural resource managers, communities and politicians in the western United States. Area affected by wildfire has climbed steadily over the last twenty years and is expected to increase in the future. Recognition of the importance of both social and biophysical influences on wildfire management has led to calls for integrated social-ecological research and new methods for studying ecosystems that incorporate both social and biophysical science. This project integrates social and biophysical research methods to address research questions related to wildfire, forest dynamics, and management of national forestlands in Oregon's Central Cascades. Qualitative content analysis is paired with landscape modeling to answer research questions related to managing frequent-fire forests for landscape resilience. Collectively, both approaches present a more complete understanding of challenges and opportunities related to managing for landscape resilience than could either approach on its own. One common thread identified in both approaches is the importance of bringing more fire onto the landscape, either through the use of prescribed fire or carefully managed wildfire. Both interview respondents and modeling results demonstrate the importance of using managed fire to reduce the risk of high-severity wildfire. Another compelling result of the analysis stemmed from modeling simulations which showed current levels of management to lead to the same amount of high-severity fire as a no management scenario. Finally, the modeling results demonstrated that not every acre has to be managed to reduce wildfire risk across a larger landscape. Landscape-scale management plans are thus critical to the development of effective management strategies, and forest plans may fulfill this role. Forest Service budgeting based on forest plans could lead to more efficient, effective, and responsive public administration of federal lands. Close

• 10. [Article] The Effects of Forest Fuel-Reduction Treatments in the United States

  This is the publisher’s final pdf. The published article is copyrighted by the American Institute of Biological Sciences and can be found at: http://www.aibs.org/bioscience/. To the best of our knowledge, ...

  Citation × Citation Citation Abstract Copy Title: The Effects of Forest Fuel-Reduction Treatments in the United States Author: Schwilk, Dylan W., Fontaine, Joseph B., Fettig, Christopher J., Hartsough, Bruce R., Kennedy, Patricia L., Stephens, Scott L., McIver, James D., Boerner, Ralph E. J. This is the publisher’s final pdf. The published article is copyrighted by the American Institute of Biological Sciences and can be found at: http://www.aibs.org/bioscience/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: The Effects of Forest Fuel-Reduction Treatments in the United States Author: Schwilk, Dylan W., Fontaine, Joseph B., Fettig, Christopher J., Hartsough, Bruce R., Kennedy, Patricia L., Stephens, Scott L., McIver, James D., Boerner, Ralph E. J. This is the publisher’s final pdf. The published article is copyrighted by the American Institute of Biological Sciences and can be found at: http://www.aibs.org/bioscience/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close