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• 11. [Article] Pre-logging Liana Cutting Reduces Liana Regeneration in Logging Gaps in the Eastern Brazilian Amazon

  The cutting of all lianas prior to logging is a reduced-impact logging technique that is predicted to reduce liana proliferation in logging gaps. This study compares liana abundance and species composition ...

  Citation × Citation Citation Abstract Copy Title: Pre-logging Liana Cutting Reduces Liana Regeneration in Logging Gaps in the Eastern Brazilian Amazon Author: Gerwing, Jeffrey J., Uhl, Christopher Year: 2002 The cutting of all lianas prior to logging is a reduced-impact logging technique that is predicted to reduce liana proliferation in logging gaps. This study compares liana abundance and species composition in gaps created during conventional and reduced-impact logging in a forest of the eastern Brazilian Amazon. Logging treatments were conducted in side-by-side plots. Shortly following logging, 50-m2 plots were located in the approximate centers of four single treefall and four multiple treefall gaps in each logging area. Six years following logging, there were ∼40% fewer climbing lianas in reduced-impact gaps than in conventional logging gaps. In both logging areas multiple-tree gaps had higher liana densities and a higher proportion of lianas recruiting from seed than single tree gaps, where sprouts from cut or fallen lianas were more common. The mean number of liana species encountered per plot did not differ among treatments nor was there any significant difference in species diversity (Fisher's α) between logging treatments. The results of this study suggest that pre-logging liana cutting can significantly reduce post-logging liana proliferation in gaps, with no discernible negative impact on the species diversity of regenerating lianas. Title: Pre-logging Liana Cutting Reduces Liana Regeneration in Logging Gaps in the Eastern Brazilian Amazon Author: Gerwing, Jeffrey J., Uhl, Christopher Year: 2002 The cutting of all lianas prior to logging is a reduced-impact logging technique that is predicted to reduce liana proliferation in logging gaps. This study compares liana abundance and species composition in gaps created during conventional and reduced-impact logging in a forest of the eastern Brazilian Amazon. Logging treatments were conducted in side-by-side plots. Shortly following logging, 50-m2 plots were located in the approximate centers of four single treefall and four multiple treefall gaps in each logging area. Six years following logging, there were ∼40% fewer climbing lianas in reduced-impact gaps than in conventional logging gaps. In both logging areas multiple-tree gaps had higher liana densities and a higher proportion of lianas recruiting from seed than single tree gaps, where sprouts from cut or fallen lianas were more common. The mean number of liana species encountered per plot did not differ among treatments nor was there any significant difference in species diversity (Fisher's α) between logging treatments. The results of this study suggest that pre-logging liana cutting can significantly reduce post-logging liana proliferation in gaps, with no discernible negative impact on the species diversity of regenerating lianas. Close

• 12. [Article] Increasing the Reliability of Ecological Models Using Modern Software Engineering Techniques

  Modern software development techniques are largely unknown to ecologists. Typically, ecological models and other software tools are developed for limited research purposes, and additional capabilities ...

  Citation × Citation Citation Abstract Copy Title: Increasing the Reliability of Ecological Models Using Modern Software Engineering Techniques Author: Scheller, Robert M., Sturtevant, Brian R., Gustafson, Eric J., Ward, Brendan C., Mladenoff, David J. Year: 2009 Modern software development techniques are largely unknown to ecologists. Typically, ecological models and other software tools are developed for limited research purposes, and additional capabilities are added later, usually in an ad hoc manner. Modern software engineering techniques can substantially increase scientific rigor and confidence in ecological models and tools. These techniques have the potential to transform how ecological software is conceived and developed, improve precision, reduce errors, and increase scientific credibility. We describe our re-engineering of the forest landscape model LANDIS (LANdscape DIsturbance and Succession) to illustrate the advantages of using common software engineering practices. Title: Increasing the Reliability of Ecological Models Using Modern Software Engineering Techniques Author: Scheller, Robert M., Sturtevant, Brian R., Gustafson, Eric J., Ward, Brendan C., Mladenoff, David J. Year: 2009 Modern software development techniques are largely unknown to ecologists. Typically, ecological models and other software tools are developed for limited research purposes, and additional capabilities are added later, usually in an ad hoc manner. Modern software engineering techniques can substantially increase scientific rigor and confidence in ecological models and tools. These techniques have the potential to transform how ecological software is conceived and developed, improve precision, reduce errors, and increase scientific credibility. We describe our re-engineering of the forest landscape model LANDIS (LANdscape DIsturbance and Succession) to illustrate the advantages of using common software engineering practices. Close

• 13. [Article] Residential Edges as Ecological Traps: Postfledgling Survival of a Ground-Nesting Passerine in a Forested Urban Park

  Substantial offspring mortality can occur during the postfledging period of birds, but few postfledging survival studies have been conducted within the context of habitat suitability. We conducted a 2-year ...

  Citation × Citation Citation Abstract Copy Title: Residential Edges as Ecological Traps: Postfledgling Survival of a Ground-Nesting Passerine in a Forested Urban Park Author: Shipley, Amy A., Murphy, Michael T., Elzinga, Adam H. Year: 2013 Substantial offspring mortality can occur during the postfledging period of birds, but few postfledging survival studies have been conducted within the context of habitat suitability. We conducted a 2-year radiotelemetry study of Spotted Towhee (Pipilo maculatus) reproductive success and fledgling survival in a 24-ha forested park in a residential area of Lake Oswego, Oregon. In corroboration of previous research on this species, we found (1) that Spotted Towhees nested closer to the edge between the park and residential neighborhoods than expected by chance, and (2) that pairs nesting near edges produced the largest and most offspring. However, fates were reversed during the postfledging period. Thirty-six of 52 fledglings survived the 27-day tracking period, and although fledglings were more likely to be found near edges than in the interior, fledglings near edges had a far higher probability of dying. All deaths were from predation, and at least 11 of 16 predation events were attributable to Domestic Cats (Felis catus) and Western Screech-Owls (Megascops kennicottii). A stochastic model that incorporated probability of nest success, nestling production from successful nests, and fledgling survival showed that the number of independent offspring produced per nest was greatest in the park interior. Heavy use of, and apparent preference for, edge by nesting Spotted Towhees, coupled with high fledgling mortality near edges, created a severe ecological trap that was not apparent until the final stage of parental care. Hence, failure to document offspring survival in the late stages of reproduction may lead to incorrect assessment of habitat suitability and poor management decisions. Title: Residential Edges as Ecological Traps: Postfledgling Survival of a Ground-Nesting Passerine in a Forested Urban Park Author: Shipley, Amy A., Murphy, Michael T., Elzinga, Adam H. Year: 2013 Substantial offspring mortality can occur during the postfledging period of birds, but few postfledging survival studies have been conducted within the context of habitat suitability. We conducted a 2-year radiotelemetry study of Spotted Towhee (Pipilo maculatus) reproductive success and fledgling survival in a 24-ha forested park in a residential area of Lake Oswego, Oregon. In corroboration of previous research on this species, we found (1) that Spotted Towhees nested closer to the edge between the park and residential neighborhoods than expected by chance, and (2) that pairs nesting near edges produced the largest and most offspring. However, fates were reversed during the postfledging period. Thirty-six of 52 fledglings survived the 27-day tracking period, and although fledglings were more likely to be found near edges than in the interior, fledglings near edges had a far higher probability of dying. All deaths were from predation, and at least 11 of 16 predation events were attributable to Domestic Cats (Felis catus) and Western Screech-Owls (Megascops kennicottii). A stochastic model that incorporated probability of nest success, nestling production from successful nests, and fledgling survival showed that the number of independent offspring produced per nest was greatest in the park interior. Heavy use of, and apparent preference for, edge by nesting Spotted Towhees, coupled with high fledgling mortality near edges, created a severe ecological trap that was not apparent until the final stage of parental care. Hence, failure to document offspring survival in the late stages of reproduction may lead to incorrect assessment of habitat suitability and poor management decisions. Close

• 14. [Article] Northwest Forest Plan The First 20 Years (1994-2013): Watershed Condition Status and Trend

  We used two data sets to evaluate stream and upslope/riparian condition for sixth-field watersheds in each aquatic province within the Northwest Forest Plan (NWFP) area. The stream evaluation was based ...

  Citation × Citation Citation Abstract Copy Title: Northwest Forest Plan The First 20 Years (1994-2013): Watershed Condition Status and Trend Author: Miller, Stephanie A., Gordon, Sean N, Eldred, Peter, Beloin, Ronald M., Wilcox, Steve, Raggon, Mark, Andersen, Heidi, Muldoon, Ariel Year: 2015 We used two data sets to evaluate stream and upslope/riparian condition for sixth-field watersheds in each aquatic province within the Northwest Forest Plan (NWFP) area. The stream evaluation was based on stream sampling data collected from 2002 to the 2013 (214 watersheds) as part of an eight year repeating (rotating) sample design. We are currently halfway through our second rotation of stream sampling, and have repeated 110 watersheds since the second rotation began in 2009. The analysis presented in this report uses roughly half the number of watersheds as was originally intended by the sample design since re-visitation will not be completed until 2017. In the meantime, we compare the first rotation of visits (2002-2009) to the first four years of the second rotation (2010-2013) giving us a general idea of current patterns. To evaluate stream condition we used a reference condition nearest neighbor statistical approach to calculate the stream physical habitat scores based on substrate, wood, and pool metrics for each watershed. Macroinvertebrates and water temperature were analyzed separately from physical habitat and provide additional assessment of overall watershed condition. Scores for both stream and upslope/riparian conditions were normalized to fall between 0 (poor) and 100 (good). Title: Northwest Forest Plan The First 20 Years (1994-2013): Watershed Condition Status and Trend Author: Miller, Stephanie A., Gordon, Sean N, Eldred, Peter, Beloin, Ronald M., Wilcox, Steve, Raggon, Mark, Andersen, Heidi, Muldoon, Ariel Year: 2015 We used two data sets to evaluate stream and upslope/riparian condition for sixth-field watersheds in each aquatic province within the Northwest Forest Plan (NWFP) area. The stream evaluation was based on stream sampling data collected from 2002 to the 2013 (214 watersheds) as part of an eight year repeating (rotating) sample design. We are currently halfway through our second rotation of stream sampling, and have repeated 110 watersheds since the second rotation began in 2009. The analysis presented in this report uses roughly half the number of watersheds as was originally intended by the sample design since re-visitation will not be completed until 2017. In the meantime, we compare the first rotation of visits (2002-2009) to the first four years of the second rotation (2010-2013) giving us a general idea of current patterns. To evaluate stream condition we used a reference condition nearest neighbor statistical approach to calculate the stream physical habitat scores based on substrate, wood, and pool metrics for each watershed. Macroinvertebrates and water temperature were analyzed separately from physical habitat and provide additional assessment of overall watershed condition. Scores for both stream and upslope/riparian conditions were normalized to fall between 0 (poor) and 100 (good). Close

• 15. [Article] Mutual exclusion between Salmonberry and Douglas-fir in the Coast Range of Oregon

  One serious problem faced by the forest industry in the Pacific Northwest is poor regeneration of commercial trees on land which is harvested and subsequently dominated by brush species. In Coastal Oregon, ...

  Citation × Citation Citation Abstract Copy Title: Mutual exclusion between Salmonberry and Douglas-fir in the Coast Range of Oregon Author: Still, Kenneth Ray Year: 1972 One serious problem faced by the forest industry in the Pacific Northwest is poor regeneration of commercial trees on land which is harvested and subsequently dominated by brush species. In Coastal Oregon, salmonberry is one of these brush species. Detailed investigations of field sites indicate that light intensity in the brush stands was low but sufficient for germination and early growth of Douglas-fir seedlings and soil moisture percentages and nutrient levels were high enough to support early Douglas-fir growth. Laboratory tests demonstrated the presence of leachable phytotoxins in the leaves of salmonberry. The hypothesis resulting from this study is that salmonberry releases a phytotoxin that in synergism with environmental stresses (i.e., light), suppresses germination and growth of Douglas-fir seedlings in the field. Title: Mutual exclusion between Salmonberry and Douglas-fir in the Coast Range of Oregon Author: Still, Kenneth Ray Year: 1972 One serious problem faced by the forest industry in the Pacific Northwest is poor regeneration of commercial trees on land which is harvested and subsequently dominated by brush species. In Coastal Oregon, salmonberry is one of these brush species. Detailed investigations of field sites indicate that light intensity in the brush stands was low but sufficient for germination and early growth of Douglas-fir seedlings and soil moisture percentages and nutrient levels were high enough to support early Douglas-fir growth. Laboratory tests demonstrated the presence of leachable phytotoxins in the leaves of salmonberry. The hypothesis resulting from this study is that salmonberry releases a phytotoxin that in synergism with environmental stresses (i.e., light), suppresses germination and growth of Douglas-fir seedlings in the field. Close

• 16. [Article] Re-Envisioning Community-Wildfire Relations in the U.S. West as Adaptive Governance

  Prompted by a series of increasingly destructive, expensive, and highly visible wildfire crises in human communities across the globe, a robust body of scholarship has emerged to theorize, conceptualize, ...

  Citation × Citation Citation Abstract Copy Title: Re-Envisioning Community-Wildfire Relations in the U.S. West as Adaptive Governance Author: Abrams, Jesse B., Knapp, Melanie, Paveglio, Travis B., Ellison, Autumn, Moseley, Cassandra, Nielsen-Pincus, Max, Carroll, Matthew S. Year: 2015 Prompted by a series of increasingly destructive, expensive, and highly visible wildfire crises in human communities across the globe, a robust body of scholarship has emerged to theorize, conceptualize, and measure community-level resilience to wildfires. To date, however, insufficient consideration has been given to wildfire resilience as a process of adaptive governance mediated by institutions at multiple scales. Here we explore the possibilities for addressing this gap through an analysis of wildfire resilience among wildland-urban interface communities in the western region of the United States. We re-engage important but overlooked components of social-ecological system resilience by situating rural communities within their state-to national-level institutional contexts; we then analyze two communities in Nevada and New Mexico in terms of their institutional settings and responses to recent wildfire events. We frame our analysis around the concepts of scale matching, linking within and across scales, and institutional flexibility. Title: Re-Envisioning Community-Wildfire Relations in the U.S. West as Adaptive Governance Author: Abrams, Jesse B., Knapp, Melanie, Paveglio, Travis B., Ellison, Autumn, Moseley, Cassandra, Nielsen-Pincus, Max, Carroll, Matthew S. Year: 2015 Prompted by a series of increasingly destructive, expensive, and highly visible wildfire crises in human communities across the globe, a robust body of scholarship has emerged to theorize, conceptualize, and measure community-level resilience to wildfires. To date, however, insufficient consideration has been given to wildfire resilience as a process of adaptive governance mediated by institutions at multiple scales. Here we explore the possibilities for addressing this gap through an analysis of wildfire resilience among wildland-urban interface communities in the western region of the United States. We re-engage important but overlooked components of social-ecological system resilience by situating rural communities within their state-to national-level institutional contexts; we then analyze two communities in Nevada and New Mexico in terms of their institutional settings and responses to recent wildfire events. We frame our analysis around the concepts of scale matching, linking within and across scales, and institutional flexibility. Close

• 17. [Article] The allelopathic potential of Rhododendron macrophyllum in a western Cascades clearcut

  The purposes of this study were to determine if Rhododendron macrophyllum has the potential to inhibit the growth of other species through the production of water-soluble toxins which are leached out of ...

  Citation × Citation Citation Abstract Copy Title: The allelopathic potential of Rhododendron macrophyllum in a western Cascades clearcut Author: Clark, Ivan W. Year: 1979 The purposes of this study were to determine if Rhododendron macrophyllum has the potential to inhibit the growth of other species through the production of water-soluble toxins which are leached out of its litter by rainfall, and to determine if this potential is realized in the field. The study was therefore composed of two part: 1) a series of bioassays to determine the presence an activity of water-soluble phytotoxins in R. macrophyllum leaf litter, and 2) a field study to describe vegetational patterns associated with R. macrophyllum in a western Cascades clearcut. Title: The allelopathic potential of Rhododendron macrophyllum in a western Cascades clearcut Author: Clark, Ivan W. Year: 1979 The purposes of this study were to determine if Rhododendron macrophyllum has the potential to inhibit the growth of other species through the production of water-soluble toxins which are leached out of its litter by rainfall, and to determine if this potential is realized in the field. The study was therefore composed of two part: 1) a series of bioassays to determine the presence an activity of water-soluble phytotoxins in R. macrophyllum leaf litter, and 2) a field study to describe vegetational patterns associated with R. macrophyllum in a western Cascades clearcut. Close

• 18. [Article] A taxonomic study of two nominal subspecies of pikas (Ochotona princeps) in the Cascade Mountains of Oregon

  Pikas from four colonies in the Cascade Mountains of Oregon were examined. Two colonies were chosen from within the geographical distribution of two nominal subspecies. A discriminate analysis of morphological ...

  Citation × Citation Citation Abstract Copy Title: A taxonomic study of two nominal subspecies of pikas (Ochotona princeps) in the Cascade Mountains of Oregon Author: Coots, Richard M Year: 1972 Pikas from four colonies in the Cascade Mountains of Oregon were examined. Two colonies were chosen from within the geographical distribution of two nominal subspecies. A discriminate analysis of morphological measurements taken from the specimens showed that each colony could be distinguished from each other. Each colony studied showed more intra-colony similarity than inter-colony similarity regardless of distance separating the colonies or subspecies designations. The results indicate that the validity of subspecies designations for this species can be questioned. Title: A taxonomic study of two nominal subspecies of pikas (Ochotona princeps) in the Cascade Mountains of Oregon Author: Coots, Richard M Year: 1972 Pikas from four colonies in the Cascade Mountains of Oregon were examined. Two colonies were chosen from within the geographical distribution of two nominal subspecies. A discriminate analysis of morphological measurements taken from the specimens showed that each colony could be distinguished from each other. Each colony studied showed more intra-colony similarity than inter-colony similarity regardless of distance separating the colonies or subspecies designations. The results indicate that the validity of subspecies designations for this species can be questioned. Close

• 19. [Article] Effect of Spatial Influence on Endophyte Diversity Within Alnus Rubra

  Red alders (Alnus rubra) of the Pacific Northwest are characterized as actinorhizal dicotyledons; plants that possess that ability to form symbiotic relationships with endophytic organisms, which result ...

  Citation × Citation Citation Abstract Copy Title: Effect of Spatial Influence on Endophyte Diversity Within Alnus Rubra Author: Singleton, Sebastian L Year: 2017 Red alders (Alnus rubra) of the Pacific Northwest are characterized as actinorhizal dicotyledons; plants that possess that ability to form symbiotic relationships with endophytic organisms, which result in nitrogen-fixing nodules. In Alders of the order Fagales, such a symbiotic relationship with Frankia bacteria allows these plants to play crucial environmental roles as pioneer species able to colonize and enrich nutrient-deficient soils. This ability has a major impact on ecological succession by enabling other species to establish. Although inoculation with frankia bacteria is known to increase symbiotic nitrogen fixation capabilities of actinorhizal plants, whether they could confer the same benefit to other host species is unstudied. Additionally, whether diversity of endophytic communities varies between host plants of the same species is unknown. The research conducted contributes to a larger-scale research project that asks: How do foliar endophyte communities in alder and willow respond to heavy-metal air pollution in an urban environment? Whereas the smaller-scale project specifically address the diversity of foliar and nodular endophytic communities present within A. rubra inhabiting three distinct areas that are also represented in the larger-scale project. Secondary research will also be performed to characterize frankia bacteria diversity present in Alder root nodules. The significance of this study is to explore differences in foliar and nodular endophyte community assemblages expressed between three spatially distinct locations. Authors: Sebastian L. Singleton, Daniel Ballhorn Presenter: Sebastian L. Singleton Title: Effect of Spatial Influence on Endophyte Diversity Within Alnus Rubra Author: Singleton, Sebastian L Year: 2017 Red alders (Alnus rubra) of the Pacific Northwest are characterized as actinorhizal dicotyledons; plants that possess that ability to form symbiotic relationships with endophytic organisms, which result in nitrogen-fixing nodules. In Alders of the order Fagales, such a symbiotic relationship with Frankia bacteria allows these plants to play crucial environmental roles as pioneer species able to colonize and enrich nutrient-deficient soils. This ability has a major impact on ecological succession by enabling other species to establish. Although inoculation with frankia bacteria is known to increase symbiotic nitrogen fixation capabilities of actinorhizal plants, whether they could confer the same benefit to other host species is unstudied. Additionally, whether diversity of endophytic communities varies between host plants of the same species is unknown. The research conducted contributes to a larger-scale research project that asks: How do foliar endophyte communities in alder and willow respond to heavy-metal air pollution in an urban environment? Whereas the smaller-scale project specifically address the diversity of foliar and nodular endophytic communities present within A. rubra inhabiting three distinct areas that are also represented in the larger-scale project. Secondary research will also be performed to characterize frankia bacteria diversity present in Alder root nodules. The significance of this study is to explore differences in foliar and nodular endophyte community assemblages expressed between three spatially distinct locations. Authors: Sebastian L. Singleton, Daniel Ballhorn Presenter: Sebastian L. Singleton Close