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• 1. [Article] Carbon dynamics following landscape fire: influence of burn severity, climate, and stand history in the Metolius Watershed, Oregon

  Fire is a fundamental disturbance that drives terrestrial and atmospheric carbon dynamics. Previous studies have quantified fire effects on carbon cycling from local to global scales but have focused ...

  Citation × Citation Citation Abstract Copy Title: Carbon dynamics following landscape fire: influence of burn severity, climate, and stand history in the Metolius Watershed, Oregon Author: Meigs, Garrett W. Fire is a fundamental disturbance that drives terrestrial and atmospheric carbon dynamics. Previous studies have quantified fire effects on carbon cycling from local to global scales but have focused nearly exclusively on high-severity, stand-replacement fire. Since 2002, variable-severity wildfires have burned more than 65 000 ha across the east slope of the Oregon Cascades, including 4 large fires that burned ca. 50% of the forested area within the Metolius Watershed in 2002 and 2003. This thesis integrates data from 64 field plots, remote-sensing, and an ecosystem process model to investigate the effects of low-, moderate-, and high-severity fire. The primary research objectives were to: (a) quantify combustion and mortality effects on carbon pools, postfire net ecosystem production (NEP), and potential regeneration trajectories at the stand scale; (b) introduce novel remote-sensing datasets into a modeling framework to assess the importance of low- and moderate-severity fire across the landscape and region. At the stand-scale, the 3 levels of burn severity (overstory tree mortality) resulted in profoundly different impacts on combustion, mortality, postfire carbon balance, and potential regeneration trajectories. Simulated combustion ranged from 16.6 to 32.3 Mg C ha-1, or 13% to 35% of prefire aboveground carbon. C transfers from fire-induced tree mortality were larger in magnitude than combustion, as live aboveground C decreased by >90% from low- to high-severity stands. Despite this decline, total net primary productivity (NPP) was only 40% lower in high- vs. low-severity stands, reflecting a compensatory effect of non-tree NPP. Dead wood respiratory losses were small relative to C uptake (range: 10-35% of total NPP), suggesting important decomposition lags in this seasonally-arid system. Although soil C, soil respiration, and fine root NPP were conserved across severity classes, NEP declined with increasing severity, driven by trends in aboveground NPP. Postfire conifer seedling density was generally abundant and varied over 5 orders of magnitude (study-wide median: 812, range: 0 – 62 134 seedlings ha-1). Seedling density was negatively correlated with overstory mortality, whereas shrub biomass showed the opposite response, indicating a wide range of potential successional trajectories. Despite substantial combustion and mortality effects on carbon pools and fluxes, the rapid response of postfire vegetation, coupled with conservation of belowground processes, may offset long-term declines in carbon storage, indicating a surprising degree of postfire stability. These stand-scale results describe a broad range of fire effects—a high degree of pyrodiversity—but because burn severity was not evenly distributed across space, the landscape-level fire effects depend on the severity mosaic. At the landscape-scale, moderate- and low-severity fire contributed 25% and 11% of total estimated pyrogenic carbon emission, respectively (0.66 Tg C total, or ca. 2.2% of statewide anthropogenic CO2 emissions equivalent from the same 2-year period). Moderate- and low-severity fire accounted for 23% and 5% of landscape-level tree mortality, respectively, which resulted in the transfer of 2.00 Tg C from live to dead pools. This carbon transfer was ca. 3-fold higher than the one-time pulse from pyrogenic emission, but it will likely take decades for this dead wood to decompose via heterotrophic respiration. The inclusion of moderate-severity fire reduced postfire (2004) mean annual NEP by 39% compared to the high-severity only scenario; low-severity fire influence on NEP was small (additional reduction of 11% in mean NEP), likely because of high tree survivorship and the relatively lower areal coverage of low-severity fire. One year postfire, burned areas were a strong C source (net C exchange across 53 000 ha: -0.065 Tg C y-1; mean ± SD: -123 ± 110 g C m-2 y-1) vs. a prefire mean near C neutral (1997-2001 mean NEP ± SD: -5 ± 51 g C m-2 y-1). The model has been known to underestimate carbon uptake in mature and old semi-arid forests, so the prefire value is likely underestimated. Despite the resurgence of wildfire across western North America, including a substantial increase in the proportion of high-severity fire in the ecoregions studied here, low- and moderate-severity wildfire accounts for the majority of burned area in the Pacific Northwest region. This non-stand-replacement fire has important consequences for carbon loss and uptake at landscape- and regional-scales. The results from this thesis suggest that by accounting for the full gradient of fire effects, carbon modelers can substantially reduce uncertainties in key components of regional and global carbon budgets, particularly pyrogenic emissions, mortality, and NEP. Understanding the effects of disturbance variability on terrestrial carbon cycling will become increasingly important in the context of emerging regional and global carbon policies. Title: Carbon dynamics following landscape fire: influence of burn severity, climate, and stand history in the Metolius Watershed, Oregon Author: Meigs, Garrett W. Fire is a fundamental disturbance that drives terrestrial and atmospheric carbon dynamics. Previous studies have quantified fire effects on carbon cycling from local to global scales but have focused nearly exclusively on high-severity, stand-replacement fire. Since 2002, variable-severity wildfires have burned more than 65 000 ha across the east slope of the Oregon Cascades, including 4 large fires that burned ca. 50% of the forested area within the Metolius Watershed in 2002 and 2003. This thesis integrates data from 64 field plots, remote-sensing, and an ecosystem process model to investigate the effects of low-, moderate-, and high-severity fire. The primary research objectives were to: (a) quantify combustion and mortality effects on carbon pools, postfire net ecosystem production (NEP), and potential regeneration trajectories at the stand scale; (b) introduce novel remote-sensing datasets into a modeling framework to assess the importance of low- and moderate-severity fire across the landscape and region. At the stand-scale, the 3 levels of burn severity (overstory tree mortality) resulted in profoundly different impacts on combustion, mortality, postfire carbon balance, and potential regeneration trajectories. Simulated combustion ranged from 16.6 to 32.3 Mg C ha-1, or 13% to 35% of prefire aboveground carbon. C transfers from fire-induced tree mortality were larger in magnitude than combustion, as live aboveground C decreased by >90% from low- to high-severity stands. Despite this decline, total net primary productivity (NPP) was only 40% lower in high- vs. low-severity stands, reflecting a compensatory effect of non-tree NPP. Dead wood respiratory losses were small relative to C uptake (range: 10-35% of total NPP), suggesting important decomposition lags in this seasonally-arid system. Although soil C, soil respiration, and fine root NPP were conserved across severity classes, NEP declined with increasing severity, driven by trends in aboveground NPP. Postfire conifer seedling density was generally abundant and varied over 5 orders of magnitude (study-wide median: 812, range: 0 – 62 134 seedlings ha-1). Seedling density was negatively correlated with overstory mortality, whereas shrub biomass showed the opposite response, indicating a wide range of potential successional trajectories. Despite substantial combustion and mortality effects on carbon pools and fluxes, the rapid response of postfire vegetation, coupled with conservation of belowground processes, may offset long-term declines in carbon storage, indicating a surprising degree of postfire stability. These stand-scale results describe a broad range of fire effects—a high degree of pyrodiversity—but because burn severity was not evenly distributed across space, the landscape-level fire effects depend on the severity mosaic. At the landscape-scale, moderate- and low-severity fire contributed 25% and 11% of total estimated pyrogenic carbon emission, respectively (0.66 Tg C total, or ca. 2.2% of statewide anthropogenic CO2 emissions equivalent from the same 2-year period). Moderate- and low-severity fire accounted for 23% and 5% of landscape-level tree mortality, respectively, which resulted in the transfer of 2.00 Tg C from live to dead pools. This carbon transfer was ca. 3-fold higher than the one-time pulse from pyrogenic emission, but it will likely take decades for this dead wood to decompose via heterotrophic respiration. The inclusion of moderate-severity fire reduced postfire (2004) mean annual NEP by 39% compared to the high-severity only scenario; low-severity fire influence on NEP was small (additional reduction of 11% in mean NEP), likely because of high tree survivorship and the relatively lower areal coverage of low-severity fire. One year postfire, burned areas were a strong C source (net C exchange across 53 000 ha: -0.065 Tg C y-1; mean ± SD: -123 ± 110 g C m-2 y-1) vs. a prefire mean near C neutral (1997-2001 mean NEP ± SD: -5 ± 51 g C m-2 y-1). The model has been known to underestimate carbon uptake in mature and old semi-arid forests, so the prefire value is likely underestimated. Despite the resurgence of wildfire across western North America, including a substantial increase in the proportion of high-severity fire in the ecoregions studied here, low- and moderate-severity wildfire accounts for the majority of burned area in the Pacific Northwest region. This non-stand-replacement fire has important consequences for carbon loss and uptake at landscape- and regional-scales. The results from this thesis suggest that by accounting for the full gradient of fire effects, carbon modelers can substantially reduce uncertainties in key components of regional and global carbon budgets, particularly pyrogenic emissions, mortality, and NEP. Understanding the effects of disturbance variability on terrestrial carbon cycling will become increasingly important in the context of emerging regional and global carbon policies. Close

• 2. [Article] Does wildfire likelihood increase following insect outbreaks in conifer forests?

  This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecsp

  Citation × Citation Citation Abstract Copy Title: Does wildfire likelihood increase following insect outbreaks in conifer forests? Author: Shaw, David C., Campbell, John L., Bailey, John D., Kennedy, Robert E., Zald, Harold S. J., Meigs, Garrett W. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecsp Title: Does wildfire likelihood increase following insect outbreaks in conifer forests? Author: Shaw, David C., Campbell, John L., Bailey, John D., Kennedy, Robert E., Zald, Harold S. J., Meigs, Garrett W. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecsp Close

• 3. [Article] Does wildfire likelihood increase following insect outbreaks in conifer forests?

  This is the publisher’s final pdf. The published article is copyrighted by The Author(s) and published by the Ecological Society of America. It can be found at: http://www.esajournals.org/loi/ecsp

  Citation × Citation Citation Abstract Copy Title: Does wildfire likelihood increase following insect outbreaks in conifer forests? Author: Meigs, Garrett W., Campbell, John L., Bailey, John D., Kennedy, Robert E., Zald, Harold S. J., Shaw, David C. This is the publisher’s final pdf. The published article is copyrighted by The Author(s) and published by the Ecological Society of America. It can be found at: http://www.esajournals.org/loi/ecsp Title: Does wildfire likelihood increase following insect outbreaks in conifer forests? Author: Meigs, Garrett W., Campbell, John L., Bailey, John D., Kennedy, Robert E., Zald, Harold S. J., Shaw, David C. This is the publisher’s final pdf. The published article is copyrighted by The Author(s) and published by the Ecological Society of America. It can be found at: http://www.esajournals.org/loi/ecsp Close

• 4. [Article] Does wildfire likelihood increase following insect outbreaks in conifer forests?

  This is the publisher’s final pdf. The published article is copyrighted by The Author(s) and published by the Ecological Society of America. It can be found at: http://www.esajournals.org/loi/ecsp

  Citation × Citation Citation Abstract Copy Title: Does wildfire likelihood increase following insect outbreaks in conifer forests? Author: Shaw, David C., Campbell, John L., Bailey, John D., Kennedy, Robert E., Zald, Harold S. J., Meigs, Garrett W. This is the publisher’s final pdf. The published article is copyrighted by The Author(s) and published by the Ecological Society of America. It can be found at: http://www.esajournals.org/loi/ecsp Title: Does wildfire likelihood increase following insect outbreaks in conifer forests? Author: Shaw, David C., Campbell, John L., Bailey, John D., Kennedy, Robert E., Zald, Harold S. J., Meigs, Garrett W. This is the publisher’s final pdf. The published article is copyrighted by The Author(s) and published by the Ecological Society of America. It can be found at: http://www.esajournals.org/loi/ecsp Close

• 5. [Article] Forest Fire Impacts on Carbon Uptake, Storage, and Emission: The Role of Burn Severity in the Eastern Cascades, Oregon

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer ...

  Citation × Citation Citation Abstract Copy Title: Forest Fire Impacts on Carbon Uptake, Storage, and Emission: The Role of Burn Severity in the Eastern Cascades, Oregon Author: Law, Beverly E., Meigs, Garrett W., Donato, Daniel C., Campbell, John L., Martin, Jonathan G. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10021 Title: Forest Fire Impacts on Carbon Uptake, Storage, and Emission: The Role of Burn Severity in the Eastern Cascades, Oregon Author: Law, Beverly E., Meigs, Garrett W., Donato, Daniel C., Campbell, John L., Martin, Jonathan G. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10021 Close

• 6. [Article] Mapping disturbance interactions from earth and space : insect effects on tree mortality, fuels, and wildfires across forests of the Pacific Northwest

  Given the vital role of forest ecosystems in landscape pattern and process, it is important to quantify the effects, feedbacks, and uncertainties associated with forest disturbance dynamics. In western ...

  Citation × Citation Citation Abstract Copy Title: Mapping disturbance interactions from earth and space : insect effects on tree mortality, fuels, and wildfires across forests of the Pacific Northwest Author: Meigs, Garrett W. Given the vital role of forest ecosystems in landscape pattern and process, it is important to quantify the effects, feedbacks, and uncertainties associated with forest disturbance dynamics. In western North America, insects and wildfires are both native disturbances that have influenced forests for millennia, and both are projected to increase with anthropogenic climate change. Although there is acute concern that insect-caused tree mortality increases the likelihood or severity of subsequent wildfire, previous research has been mixed, with results often based on individual fire or insect events. Much of the ambivalence in the literature can be attributed to differences in the particular insect of interest, forest type, and fire event, but it is also related to the spatiotemporal scale of analysis and a general lack of geospatial datasets spanning enough time and space to capture multiple forest disturbances consistently and accurately. This dissertation presents a regional-scale framework to map, quantify, and understand insect-wildfire interactions across numerous insect and fire events across the Pacific Northwest region (PNW). Through three related studies, I worked with many collaborators to develop regionally extensive but fine-grained maps to assess the spatiotemporal patterns of wildfires and the two most pervasive, damaging forest insects in the PNW – mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins [Coleoptera: Scolytidae]; a bark beetle) and western spruce budworm (WSB; Choristoneura freemani Razowksi [Lepidoptera: Tortricidae]; a defoliator). The proximate objectives of developing new maps and summarizing where and when insects have occurred before wildfires enable us to address the ultimate question: How does forest insect activity influence the likelihood of subsequent wildfire? In a pilot study focused on the forest stand scale (Chapter Two), we leveraged a Landsat time series change detection algorithm (LandTrendr), annual forest health aerial detection surveys (ADS), and field measurements to investigate MPB and WSB effects on spectral trajectories, tree mortality, and fuel profiles at 38 plots in the Cascade Range of Oregon. Insect effects were evident in the Landsat time series as combinations of both short- and long-duration changes. WSB trajectories appeared to show a consistent temporal evolution of long-duration spectral decline followed by recovery, whereas MPB trajectories exhibited both short- and long-duration spectral declines and variable recovery rates. When comparing remote sensing data with field measurements of insect impacts, we found that spectral changes were related to cover-based estimates (e.g., tree basal area mortality and down coarse woody detritus). In contrast, ADS changes were related to count-based estimates (e.g., dead tree density). Fine woody detritus and forest floor depth were not well correlated with Landsat- or aerial survey-based change metrics. This study demonstrated the utility of insect mapping methods that capture a wide range of spectral trajectories, setting the stage for regional-scale mapping and analysis. In a regional assessment of MPB and WSB effects on tree mortality (Chapter Three), we developed Landsat-based insect maps and presented comparisons across space, time, and insect agents that have not been possible to date, complementing existing ADS maps by: (1) quantifying change in terms of field-measured tree mortality; (2) providing consistent estimates of change for multiple agents, particularly long-duration changes; (3) capturing variation of insect impacts at a finer spatial scale within ADS polygons, substantially reducing estimated insect extent. Despite high variation across the study region, spatiotemporal patterns were evident in both the ADS- and Landsat-based maps of insect activity. MPB outbreaks occurred in two phases -- first during the 1970s and 1980s in eastern and central Oregon and then more synchronously during the 2000s throughout the dry interior conifer forests of the PNW. Reflecting differences in habitat susceptibility and epidemiology, WSB outbreaks exhibited early activity in northern Washington and an apparent spread from the eastern to central PNW during the 1980s, returning to northern Washington during the 1990s and 2000s. Across the region, WSB exceeded MPB in extent and tree mortality impacts in all ecoregions except for one, suggesting that ongoing studies should account for both bark beetles and defoliators, particularly given recent and projected increases in wildfire extent. By combining these insect maps with an independent wildfire database (Chapter Four), we investigated wildfire likelihood following recent MPB and WSB outbreaks at ecoregional and regional scales. We computed wildfire likelihood with two-way binary matrices between fire and insects, testing for paired differences between percent burned with and without prior insect activity. All three disturbance agents occurred primarily in the drier, interior conifer forests east of the Cascade Range, with recent wildfires extending through the southern West Cascades and Klamath Mountains. In general, insect extent exceeded wildfire extent, and each disturbance typically affected less than 2% annually of a given ecoregion. In recent decades across the PNW, wildfire likelihood is not consistently higher in forests with prior insect outbreaks, but there is evidence of linked interactions that vary across insect agent (MPB and WSB), space (ecoregions), and time (interval since insect onset). For example, fire likelihood is higher following MPB activity in the North Cascades and West Cascades, particularly within the past 10 years, whereas fire likelihood is lower at various time lags following MPB in the Northern Rockies, East Cascades, and Blue Mountains. In contrast, fire likelihood is lower following WSB outbreaks at multiple time lags across all ecoregions. In addition, there are no consistent relationships between insect-fire likelihood and interannual fire extent, suggesting that other factors (such as climate) control the disproportionately large fire years accounting for the majority of regional fire extent. Although insects and wildfires do not appear to overlap enough to facilitate consistently positive linked disturbance interactions, specific fire events and years – such as 2003 and 2006 in the North Cascades – demonstrate high insect-fire co-occurrence and potential compound disturbance effects at the landscape scale. The results from this dissertation highlight the key ecological roles that native disturbances play in PNW forests. WSB, MPB, and wildfire have been relatively rare at the regional scale, but all three have had and will continue to have profound effects on particular forest stands and landscapes. Because scale is such an important aspect of both the disturbance phenomena themselves as well as our ability to detect the ecological changes they render, our results also underscore the importance of geospatial datasets that span multiple scales in space and time. Given concerns about forest health in a rapidly changing climate, long-term monitoring will enable forest managers to quantify and anticipate the independent and interactive effects of insects, wildfires, and other disturbances. Title: Mapping disturbance interactions from earth and space : insect effects on tree mortality, fuels, and wildfires across forests of the Pacific Northwest Author: Meigs, Garrett W. Given the vital role of forest ecosystems in landscape pattern and process, it is important to quantify the effects, feedbacks, and uncertainties associated with forest disturbance dynamics. In western North America, insects and wildfires are both native disturbances that have influenced forests for millennia, and both are projected to increase with anthropogenic climate change. Although there is acute concern that insect-caused tree mortality increases the likelihood or severity of subsequent wildfire, previous research has been mixed, with results often based on individual fire or insect events. Much of the ambivalence in the literature can be attributed to differences in the particular insect of interest, forest type, and fire event, but it is also related to the spatiotemporal scale of analysis and a general lack of geospatial datasets spanning enough time and space to capture multiple forest disturbances consistently and accurately. This dissertation presents a regional-scale framework to map, quantify, and understand insect-wildfire interactions across numerous insect and fire events across the Pacific Northwest region (PNW). Through three related studies, I worked with many collaborators to develop regionally extensive but fine-grained maps to assess the spatiotemporal patterns of wildfires and the two most pervasive, damaging forest insects in the PNW – mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins [Coleoptera: Scolytidae]; a bark beetle) and western spruce budworm (WSB; Choristoneura freemani Razowksi [Lepidoptera: Tortricidae]; a defoliator). The proximate objectives of developing new maps and summarizing where and when insects have occurred before wildfires enable us to address the ultimate question: How does forest insect activity influence the likelihood of subsequent wildfire? In a pilot study focused on the forest stand scale (Chapter Two), we leveraged a Landsat time series change detection algorithm (LandTrendr), annual forest health aerial detection surveys (ADS), and field measurements to investigate MPB and WSB effects on spectral trajectories, tree mortality, and fuel profiles at 38 plots in the Cascade Range of Oregon. Insect effects were evident in the Landsat time series as combinations of both short- and long-duration changes. WSB trajectories appeared to show a consistent temporal evolution of long-duration spectral decline followed by recovery, whereas MPB trajectories exhibited both short- and long-duration spectral declines and variable recovery rates. When comparing remote sensing data with field measurements of insect impacts, we found that spectral changes were related to cover-based estimates (e.g., tree basal area mortality and down coarse woody detritus). In contrast, ADS changes were related to count-based estimates (e.g., dead tree density). Fine woody detritus and forest floor depth were not well correlated with Landsat- or aerial survey-based change metrics. This study demonstrated the utility of insect mapping methods that capture a wide range of spectral trajectories, setting the stage for regional-scale mapping and analysis. In a regional assessment of MPB and WSB effects on tree mortality (Chapter Three), we developed Landsat-based insect maps and presented comparisons across space, time, and insect agents that have not been possible to date, complementing existing ADS maps by: (1) quantifying change in terms of field-measured tree mortality; (2) providing consistent estimates of change for multiple agents, particularly long-duration changes; (3) capturing variation of insect impacts at a finer spatial scale within ADS polygons, substantially reducing estimated insect extent. Despite high variation across the study region, spatiotemporal patterns were evident in both the ADS- and Landsat-based maps of insect activity. MPB outbreaks occurred in two phases -- first during the 1970s and 1980s in eastern and central Oregon and then more synchronously during the 2000s throughout the dry interior conifer forests of the PNW. Reflecting differences in habitat susceptibility and epidemiology, WSB outbreaks exhibited early activity in northern Washington and an apparent spread from the eastern to central PNW during the 1980s, returning to northern Washington during the 1990s and 2000s. Across the region, WSB exceeded MPB in extent and tree mortality impacts in all ecoregions except for one, suggesting that ongoing studies should account for both bark beetles and defoliators, particularly given recent and projected increases in wildfire extent. By combining these insect maps with an independent wildfire database (Chapter Four), we investigated wildfire likelihood following recent MPB and WSB outbreaks at ecoregional and regional scales. We computed wildfire likelihood with two-way binary matrices between fire and insects, testing for paired differences between percent burned with and without prior insect activity. All three disturbance agents occurred primarily in the drier, interior conifer forests east of the Cascade Range, with recent wildfires extending through the southern West Cascades and Klamath Mountains. In general, insect extent exceeded wildfire extent, and each disturbance typically affected less than 2% annually of a given ecoregion. In recent decades across the PNW, wildfire likelihood is not consistently higher in forests with prior insect outbreaks, but there is evidence of linked interactions that vary across insect agent (MPB and WSB), space (ecoregions), and time (interval since insect onset). For example, fire likelihood is higher following MPB activity in the North Cascades and West Cascades, particularly within the past 10 years, whereas fire likelihood is lower at various time lags following MPB in the Northern Rockies, East Cascades, and Blue Mountains. In contrast, fire likelihood is lower following WSB outbreaks at multiple time lags across all ecoregions. In addition, there are no consistent relationships between insect-fire likelihood and interannual fire extent, suggesting that other factors (such as climate) control the disproportionately large fire years accounting for the majority of regional fire extent. Although insects and wildfires do not appear to overlap enough to facilitate consistently positive linked disturbance interactions, specific fire events and years – such as 2003 and 2006 in the North Cascades – demonstrate high insect-fire co-occurrence and potential compound disturbance effects at the landscape scale. The results from this dissertation highlight the key ecological roles that native disturbances play in PNW forests. WSB, MPB, and wildfire have been relatively rare at the regional scale, but all three have had and will continue to have profound effects on particular forest stands and landscapes. Because scale is such an important aspect of both the disturbance phenomena themselves as well as our ability to detect the ecological changes they render, our results also underscore the importance of geospatial datasets that span multiple scales in space and time. Given concerns about forest health in a rapidly changing climate, long-term monitoring will enable forest managers to quantify and anticipate the independent and interactive effects of insects, wildfires, and other disturbances. Close

• 7. [Article] Spatiotemporal dynamics of recent mountain pine beetle and western spruce budworm outbreaks across the Pacific Northwest Region, USA

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Spatiotemporal dynamics of recent mountain pine beetle and western spruce budworm outbreaks across the Pacific Northwest Region, USA Author: Meigs, Garrett W., Gregory, Matthew J., Gray, Andrew N., Kennedy, Robert E. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/forest-ecology-and-management Title: Spatiotemporal dynamics of recent mountain pine beetle and western spruce budworm outbreaks across the Pacific Northwest Region, USA Author: Meigs, Garrett W., Gregory, Matthew J., Gray, Andrew N., Kennedy, Robert E. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/forest-ecology-and-management Close

• 8. [Article] A Landsat time series approach to characterize bark beetle and defoliator impacts on tree mortality and surface fuels in conifer forests

  This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/.

  Citation × Citation Citation Abstract Copy Title: A Landsat time series approach to characterize bark beetle and defoliator impacts on tree mortality and surface fuels in conifer forests Author: Meigs, Garrett W., Cohen, Warren B., Kennedy, Robert E. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/. Title: A Landsat time series approach to characterize bark beetle and defoliator impacts on tree mortality and surface fuels in conifer forests Author: Meigs, Garrett W., Cohen, Warren B., Kennedy, Robert E. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/. Close