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• 1. [Article] Western Juniper (Juniperus occidentalis) distribution, Bear Creek Buttes, Deschutes County, Oregon: some possible ecological and cultural influences

  Citation × Citation Citation Abstract Copy Title: Western Juniper (Juniperus occidentalis) distribution, Bear Creek Buttes, Deschutes County, Oregon: some possible ecological and cultural influences Author: Frates, Dennis Marshall Title: Western Juniper (Juniperus occidentalis) distribution, Bear Creek Buttes, Deschutes County, Oregon: some possible ecological and cultural influences Author: Frates, Dennis Marshall Close

• 2. [Article] The-island_nnl_evaluation_final.pdf

  Citation × Citation Citation Abstract Copy Title: The-island_nnl_evaluation_final.pdf Author: Murray, Michael, Kagan, James S., Schuller, Reid Title: The-island_nnl_evaluation_final.pdf Author: Murray, Michael, Kagan, James S., Schuller, Reid Close

• 3. [Article] The_Island.pptx

  Citation × Citation Citation Abstract Copy Title: The_Island.pptx Author: Schuller, Reid, Kagan, James S., Murray, Michael Title: The_Island.pptx Author: Schuller, Reid, Kagan, James S., Murray, Michael Close

• 4. [Article] Evaluation of The Island Jefferson County, Oregon for its merit in meeting national significance criteria as a National Natural Landmark to represent Pumice Western Juniper (Juniperus occidentalis) in the Columbia Plateau Province

  The National Natural Landmarks (NNL) Program encourages the preservation of exceptional examples of the Nation’s biological and geological features. To qualify for NNL designation, a site must be one of ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of The Island Jefferson County, Oregon for its merit in meeting national significance criteria as a National Natural Landmark to represent Pumice Western Juniper (Juniperus occidentalis) in the Columbia Plateau Province Author: Schuller, Reid, Kagan, James S., Murray, Michael The National Natural Landmarks (NNL) Program encourages the preservation of exceptional examples of the Nation’s biological and geological features. To qualify for NNL designation, a site must be one of the best examples of a geological or biological feature within a biophysiographic province. The Island is an isolated plateau located at the confluence of the Deschutes and Crooked Rivers in Crook County, Oregon. In 1987, it was identified as a potentially outstanding example of western juniper ecosystems as part of the Columbia Plateau biophysiographic province, Ecological Themes evaluation (Kagan et al. 1987a). The Island is an Research Natural Area (RNA), which is jointly owned and managed by the Bureau of Land Management (BLM) and the U.S. Forest Service (USFS). It is our recommendation that The Island PNNL meets the national significance criteria required for the NNL Program. Title: Evaluation of The Island Jefferson County, Oregon for its merit in meeting national significance criteria as a National Natural Landmark to represent Pumice Western Juniper (Juniperus occidentalis) in the Columbia Plateau Province Author: Schuller, Reid, Kagan, James S., Murray, Michael The National Natural Landmarks (NNL) Program encourages the preservation of exceptional examples of the Nation’s biological and geological features. To qualify for NNL designation, a site must be one of the best examples of a geological or biological feature within a biophysiographic province. The Island is an isolated plateau located at the confluence of the Deschutes and Crooked Rivers in Crook County, Oregon. In 1987, it was identified as a potentially outstanding example of western juniper ecosystems as part of the Columbia Plateau biophysiographic province, Ecological Themes evaluation (Kagan et al. 1987a). The Island is an Research Natural Area (RNA), which is jointly owned and managed by the Bureau of Land Management (BLM) and the U.S. Forest Service (USFS). It is our recommendation that The Island PNNL meets the national significance criteria required for the NNL Program. Close

• 5. [Article] Western juniper (Juniperus occidentalis)

  Reprinted June 1973. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog...

  Citation × Citation Citation Abstract Copy Title: Western juniper (Juniperus occidentalis) Author: Cornett, Elgin, Oregon State University. Cooperative Extension Service, Oregon State University. Extension Service Reprinted June 1973. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Western juniper (Juniperus occidentalis) Author: Cornett, Elgin, Oregon State University. Cooperative Extension Service, Oregon State University. Extension Service Reprinted June 1973. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 6. [Article] Western Juniper (Juniperus occidentalis) Ecology with an Exercise in Remote Sensing Techniques

  Western juniper (Juniperus occidentalis var. occidentalis) has been expanding its biogeographic range since the mid-1800's, resulting in decreased biodiversity, altered wildlife habitat, increased soil ...

  Citation × Citation Citation Abstract Copy Title: Western Juniper (Juniperus occidentalis) Ecology with an Exercise in Remote Sensing Techniques Author: Goralski, Elizabeth A. Year: 2008 Western juniper (Juniperus occidentalis var. occidentalis) has been expanding its biogeographic range since the mid-1800's, resulting in decreased biodiversity, altered wildlife habitat, increased soil erosion, reduced stream flows and reduced forage production. The direct causes of western juniper aforestation are unclear but appear to be related to altered fire regimes, over grazing, and climatic shifts. This study seeks to determine how Landsat images combined with Digital Orthoquads (DOQs) can be used to examine the geographic distribution of western juniper. Satellite imagery has yet to be applied to the large scale mapping of western juniper aforestation, resulting in the lack of regional and landscape level monitoring of western juniper range expansion. Remote sensing technologies, when combined with geographical information systems provide potentially valuable tools for monitoring western juniper expansion because of their abilities to assess large scale coverage of scenes, high cost effectiveness, and minimal field crew requirements. The two main objectives of my research are to review and summarize current literature regarding western juniper expansion and explore how remote sensing techniques may be used to quantify the expansion of the species. The results of my studies suggest that large patches of western juniper are detectable using Landsat imagery. Title: Western Juniper (Juniperus occidentalis) Ecology with an Exercise in Remote Sensing Techniques Author: Goralski, Elizabeth A. Year: 2008 Western juniper (Juniperus occidentalis var. occidentalis) has been expanding its biogeographic range since the mid-1800's, resulting in decreased biodiversity, altered wildlife habitat, increased soil erosion, reduced stream flows and reduced forage production. The direct causes of western juniper aforestation are unclear but appear to be related to altered fire regimes, over grazing, and climatic shifts. This study seeks to determine how Landsat images combined with Digital Orthoquads (DOQs) can be used to examine the geographic distribution of western juniper. Satellite imagery has yet to be applied to the large scale mapping of western juniper aforestation, resulting in the lack of regional and landscape level monitoring of western juniper range expansion. Remote sensing technologies, when combined with geographical information systems provide potentially valuable tools for monitoring western juniper expansion because of their abilities to assess large scale coverage of scenes, high cost effectiveness, and minimal field crew requirements. The two main objectives of my research are to review and summarize current literature regarding western juniper expansion and explore how remote sensing techniques may be used to quantify the expansion of the species. The results of my studies suggest that large patches of western juniper are detectable using Landsat imagery. Close

• 7. [Article] Relationship between allometric variables and biomass in western juniper (Juniperus occidentalis)

  A tenfold expansion of western juniper (Juniperus occidentalis spp. occidentalis) into the sagebrush steppe has led to the degradation of the economic and ecological potential of these landscapes. Land ...

  Citation × Citation Citation Abstract Copy Title: Relationship between allometric variables and biomass in western juniper (Juniperus occidentalis) Author: Sabin, Breanna S. A tenfold expansion of western juniper (Juniperus occidentalis spp. occidentalis) into the sagebrush steppe has led to the degradation of the economic and ecological potential of these landscapes. Land managers have enacted numerous methods to reduce distributions and densities of these trees. Assessment of above ground juniper biomass, expressed overall as well as in each of four fuel - size classes is useful information to land managers for several reasons. These include: enhance smoke management for prescribed burns, appraise feasibility of locating biomass cogeneration power plants, and extrapolating known nutrient and carbon concentrations contained within juniper to the landscape scale. Two sites were selected within Lake County, OR for this research. Allometric measurements including canopy area, canopy volume, age, height, basal diameter were taken from 129 trees and 56 of these were destructively sampled to obtain biomass of each tree; by size classes as well as over all. Regression statistics were utilized to find the correlation between allometric and biomass measurements. Of the allometric variables measured for this research, canopy volume, canopy area, and basal diameter were the strongest predictors of biomass found, with respective R2 values of 0.88, 0.87, 0.81. The proportion of biomass within each of the four size classes was: 34% for size class 1, 15% for size class 2, 23% for size class 3, and 28% for size class 4. Average biomass for these sites was 2,482 kg/ha for the Fort Rock site and 5,410 kg/ha for the Lakeview site. These models can be used to estimate biomass for co-generation plants, estimate nutrient pools and fuel loads, and predict changes in community biomass based on species or growth form groups. Title: Relationship between allometric variables and biomass in western juniper (Juniperus occidentalis) Author: Sabin, Breanna S. A tenfold expansion of western juniper (Juniperus occidentalis spp. occidentalis) into the sagebrush steppe has led to the degradation of the economic and ecological potential of these landscapes. Land managers have enacted numerous methods to reduce distributions and densities of these trees. Assessment of above ground juniper biomass, expressed overall as well as in each of four fuel - size classes is useful information to land managers for several reasons. These include: enhance smoke management for prescribed burns, appraise feasibility of locating biomass cogeneration power plants, and extrapolating known nutrient and carbon concentrations contained within juniper to the landscape scale. Two sites were selected within Lake County, OR for this research. Allometric measurements including canopy area, canopy volume, age, height, basal diameter were taken from 129 trees and 56 of these were destructively sampled to obtain biomass of each tree; by size classes as well as over all. Regression statistics were utilized to find the correlation between allometric and biomass measurements. Of the allometric variables measured for this research, canopy volume, canopy area, and basal diameter were the strongest predictors of biomass found, with respective R2 values of 0.88, 0.87, 0.81. The proportion of biomass within each of the four size classes was: 34% for size class 1, 15% for size class 2, 23% for size class 3, and 28% for size class 4. Average biomass for these sites was 2,482 kg/ha for the Fort Rock site and 5,410 kg/ha for the Lakeview site. These models can be used to estimate biomass for co-generation plants, estimate nutrient pools and fuel loads, and predict changes in community biomass based on species or growth form groups. Close

• 8. [Article] Development and morphology of juvenile western juniper (Juniperus occidentalis Hook.)

  Whole tree excavation of 41 western juniper (Juniperus occidentalis Hook.), ranging in age from 2 to 34 years old, was used to assess the development and structure of root systems, to determine biomass ...

  Citation × Citation Citation Abstract Copy Title: Development and morphology of juvenile western juniper (Juniperus occidentalis Hook.) Author: Kramer, Susanne Whole tree excavation of 41 western juniper (Juniperus occidentalis Hook.), ranging in age from 2 to 34 years old, was used to assess the development and structure of root systems, to determine biomass allocation patterns, and to develop mathematical relationships for estimating biomass and root system dimensions in seedling and young western juniper. Both aboveground and belowground developmental patterns, including structural components and vertical and horizontal root spread, were described relative to plant age. Tree age and height were evaluated as predictors of biomass, root length, and root system dimensions of juvenile western juniper. Seedling root systems consisted of a relatively short tap root and a few weak laterals. With advancing age, root systems expanded in depth and lateral spread. Maximum observed rooting depth and horizontal extension were 1.20 m and 5.70 m, respectively. Root biomass and length allocation shifted from tap to lateral roots with increasing plant age. Lateral root growth dominated in trees older than 10 years. The majority of lateral roots emerged from the tap root between 5 and 20 cm from the soil surface. The relative proportions of accumulated weight in shoot components changed with progressing age. Foliage biomass accounted for the largest fraction of total standing weight throughout the developmental period examined. Adult foliage was first initiated at 17 years of age. Structural tissue increased and dead biomass decreased in relative proportion as the trees grew. Western juniper root/shoot biomass ratios ranged from 0.50 to 1.75 and showed little correlation with age. Fine root/foliage ratios varied between 0.85 and 4.38, and exhibited a significant decline with age. Tree age and height were consistently strong predictors for biomass of root and shoot components, root system length, and extension. Coefficients of determination from regressions on log-log transformed data ranged from 0.70 to 0.92 for tree age and from 0.84 to 0.96 for tree height. Title: Development and morphology of juvenile western juniper (Juniperus occidentalis Hook.) Author: Kramer, Susanne Whole tree excavation of 41 western juniper (Juniperus occidentalis Hook.), ranging in age from 2 to 34 years old, was used to assess the development and structure of root systems, to determine biomass allocation patterns, and to develop mathematical relationships for estimating biomass and root system dimensions in seedling and young western juniper. Both aboveground and belowground developmental patterns, including structural components and vertical and horizontal root spread, were described relative to plant age. Tree age and height were evaluated as predictors of biomass, root length, and root system dimensions of juvenile western juniper. Seedling root systems consisted of a relatively short tap root and a few weak laterals. With advancing age, root systems expanded in depth and lateral spread. Maximum observed rooting depth and horizontal extension were 1.20 m and 5.70 m, respectively. Root biomass and length allocation shifted from tap to lateral roots with increasing plant age. Lateral root growth dominated in trees older than 10 years. The majority of lateral roots emerged from the tap root between 5 and 20 cm from the soil surface. The relative proportions of accumulated weight in shoot components changed with progressing age. Foliage biomass accounted for the largest fraction of total standing weight throughout the developmental period examined. Adult foliage was first initiated at 17 years of age. Structural tissue increased and dead biomass decreased in relative proportion as the trees grew. Western juniper root/shoot biomass ratios ranged from 0.50 to 1.75 and showed little correlation with age. Fine root/foliage ratios varied between 0.85 and 4.38, and exhibited a significant decline with age. Tree age and height were consistently strong predictors for biomass of root and shoot components, root system length, and extension. Coefficients of determination from regressions on log-log transformed data ranged from 0.70 to 0.92 for tree age and from 0.84 to 0.96 for tree height. Close

• 9. [Article] Assessing the Carbon Consequences of Western Juniper (Juniperus occidentalis) Encroachment Across Oregon, USA

  This is the publisher’s final pdf. The published article is copyrighted by Society for Range Management and can be found at: http://www.srmjournals.org/toc/rama/0/0. To the best of our knowledge, one or ...

  Citation × Citation Citation Abstract Copy Title: Assessing the Carbon Consequences of Western Juniper (Juniperus occidentalis) Encroachment Across Oregon, USA Author: Kennedy, Robert E., Campbell, John L., Miller, Richard F., Cohen, Warren B. This is the publisher’s final pdf. The published article is copyrighted by Society for Range Management and can be found at: http://www.srmjournals.org/toc/rama/0/0. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Assessing the Carbon Consequences of Western Juniper (Juniperus occidentalis) Encroachment Across Oregon, USA Author: Kennedy, Robert E., Campbell, John L., Miller, Richard F., Cohen, Warren B. This is the publisher’s final pdf. The published article is copyrighted by Society for Range Management and can be found at: http://www.srmjournals.org/toc/rama/0/0. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 10. [Article] Resistance of Selected Wood-Based Materials to Fungal and Termite Attack in Non–Soil Contact Exposures

  The resistance of three naturally durable heartwood species and a stranded giant bamboo product to fungal and termite (Coptotermes formosanus) attack was evaluated at a test site located near Hilo, Hawaii. ...

  Citation × Citation Citation Abstract Copy Title: Resistance of Selected Wood-Based Materials to Fungal and Termite Attack in Non–Soil Contact Exposures Author: Morrell, Jeffrey J. The resistance of three naturally durable heartwood species and a stranded giant bamboo product to fungal and termite (Coptotermes formosanus) attack was evaluated at a test site located near Hilo, Hawaii. Merbau (Intsia bijuga or I. palembanica) and ipe (Tabebuia spp.) were both exceptionally resistant to fungal and termite attack, while western juniper (Juniperus occidentalis) heartwood was slightly less resistant to degradation. The presence of heartwood on western juniper samples had no noticeable effect on the performance of adjacent sapwood. The bamboo decking proved to the least durable of the materials and experienced substantial termite and fungal attack over the 32-month test period. Title: Resistance of Selected Wood-Based Materials to Fungal and Termite Attack in Non–Soil Contact Exposures Author: Morrell, Jeffrey J. The resistance of three naturally durable heartwood species and a stranded giant bamboo product to fungal and termite (Coptotermes formosanus) attack was evaluated at a test site located near Hilo, Hawaii. Merbau (Intsia bijuga or I. palembanica) and ipe (Tabebuia spp.) were both exceptionally resistant to fungal and termite attack, while western juniper (Juniperus occidentalis) heartwood was slightly less resistant to degradation. The presence of heartwood on western juniper samples had no noticeable effect on the performance of adjacent sapwood. The bamboo decking proved to the least durable of the materials and experienced substantial termite and fungal attack over the 32-month test period. Close

• 11. [Article] Tree cover mapping for assessing greater sage-grouse habitat in Eastern Oregon

  This project used a predictive model to map canopy cover of vegetation over seven feet in height (“tall woody vegetation”) at 30-meter resolution over nearly 29 million acres within and adjacent to the ...

  Citation × Citation Citation Abstract Copy Title: Tree cover mapping for assessing greater sage-grouse habitat in Eastern Oregon Author: Nielsen, Eric, Noone, Matt This project used a predictive model to map canopy cover of vegetation over seven feet in height (“tall woody vegetation”) at 30-meter resolution over nearly 29 million acres within and adjacent to the range of the greater sage-grouse in Oregon. Although the specific target of the mapping was western juniper (Juniperus occidentalis), reference data did not permit separating juniper from other tall woody vegetation during the predictive modeling process. The majority of the tall woody vegetation within the project area is western juniper. However, in high elevation regions, riparian, wetland, and residential areas, other vegetation is occasionally represented. The methodology discussed here produces raw modeled data. Title: Tree cover mapping for assessing greater sage-grouse habitat in Eastern Oregon Author: Nielsen, Eric, Noone, Matt This project used a predictive model to map canopy cover of vegetation over seven feet in height (“tall woody vegetation”) at 30-meter resolution over nearly 29 million acres within and adjacent to the range of the greater sage-grouse in Oregon. Although the specific target of the mapping was western juniper (Juniperus occidentalis), reference data did not permit separating juniper from other tall woody vegetation during the predictive modeling process. The majority of the tall woody vegetation within the project area is western juniper. However, in high elevation regions, riparian, wetland, and residential areas, other vegetation is occasionally represented. The methodology discussed here produces raw modeled data. Close

• 12. [Article] Resource Selection and Space Use of Western Long-eared Myotis (Myotis evotis) in a Western Juniper (Juniperus occidentalis) Woodland of Central Oregon

  Identifying habitat and spatial requirements of wildlife species across multiple spatial scales is a challenging, yet crucial component of wildlife management. Habitat use of bats is particularly difficult ...

  Citation × Citation Citation Abstract Copy Title: Resource Selection and Space Use of Western Long-eared Myotis (Myotis evotis) in a Western Juniper (Juniperus occidentalis) Woodland of Central Oregon Author: Anthony, Christopher R. (Christopher Ross) Identifying habitat and spatial requirements of wildlife species across multiple spatial scales is a challenging, yet crucial component of wildlife management. Habitat use of bats is particularly difficult to study, and managing habitat to conserve bats is especially challenging because bats are highly vagile organisms that exploit several different types of habitat across many spatio-temporal scales. The status and distribution of bat populations is determined by the spatio-temporal pattern of quality roost sites and foraging areas across the landscape. However, knowledge of these limiting resources for bats and their distribution on the landscape is poorly known in western juniper (Juniperus occidentalis ssp. occidentalis) woodlands, even though at least 16 species of bat occur in these habitats across the western United States. Identifying habitat use by bats in western juniper woodlands is especially important due to recent landscape-scale efforts to remove juniper trees to improve habitat for greater sage-grouse (Centrocercus urophasianus), a species of major conservation concern in shrub-steppe habitats. Thus, the urgent challenge for land management agencies in western North America is to identify bat day roost and foraging sites in order to develop management guidelines to conserve bats and their critical habitats. The specific objective of this study was to identify habitat characteristics that are important to western long-eared myotis (Myotis evotis) during the reproductive season in western juniper woodland of central Oregon. I used radio telemetry to find day roost sites and investigate selection criteria for these sites by lactating female and male bats. I studied day roost site selection at three spatial scales: roost, plot, and home range. I found that females prefer to roost in rocks rather than in trees, whereas males did not display a preference towards either type of roost substrate. Bats that roosted in trees used primarily pre-settlement junipers (> 150 years old) with at least one cavity, and bats that roosted in rocks used primarily formations consisting on multiple boulders. More available roost sites within 17.8 m of a tree roost site (or within 5 m of a rock roost site) was associated with an increased likelihood that a particular tree or rock roost site was selected. Males selected rock roosts that had greater area of pre-settlement woodlands than shrub-steppe within a 1 km radius. These results suggest that roost site selection differs between lactating females and males and occurs at multiple spatial scales. Land management practices that retain pre-settlement trees during juniper removal treatments and protect areas with high densities of roost sites near water sources are likely to conserve or restore bat populations. I also estimated home range size and the maximum foraging range of bats. Estimates of mean home range size were the largest ever reported for western long-eared myotis and among the largest for any Myotis species so far studied in North America. The mean 95% home range size for lactating females was 205.85 ha (SE = 47.94) and for males was 424.2 ha (SE = 187.2). The mean maximum foraging range for lactating females was 933 m (SE = 284.9) and males was 1522 m (SE = 532.8). Estimates of mean home range size and maximum foraging range did not differ between lactating females and males; however, low statistical power likely precluded detecting a difference. Lastly, I examined habitat selection at two spatial scales, (1) home range selection on the landscape scale and (2) foraging habitat selection within the home range. The probability of a location being selected by either lactating female or male bats decreased with increasing distance from day roost sites and water sources. Lactating females selected pre-settlement woodlands more than shrub-steppe habitat during foraging, but avoided areas with > 20% tree canopy cover more than areas with no canopy cover at the landscape scale. Males selected areas with 0.1% to 10% tree canopy cover more than areas with no canopy cover at the home range scale. To maintain foraging habitat for M. evotis in the study area, pre-settlement woodlands that are located near roost sites and water sources should be managed for variable tree densities. Title: Resource Selection and Space Use of Western Long-eared Myotis (Myotis evotis) in a Western Juniper (Juniperus occidentalis) Woodland of Central Oregon Author: Anthony, Christopher R. (Christopher Ross) Identifying habitat and spatial requirements of wildlife species across multiple spatial scales is a challenging, yet crucial component of wildlife management. Habitat use of bats is particularly difficult to study, and managing habitat to conserve bats is especially challenging because bats are highly vagile organisms that exploit several different types of habitat across many spatio-temporal scales. The status and distribution of bat populations is determined by the spatio-temporal pattern of quality roost sites and foraging areas across the landscape. However, knowledge of these limiting resources for bats and their distribution on the landscape is poorly known in western juniper (Juniperus occidentalis ssp. occidentalis) woodlands, even though at least 16 species of bat occur in these habitats across the western United States. Identifying habitat use by bats in western juniper woodlands is especially important due to recent landscape-scale efforts to remove juniper trees to improve habitat for greater sage-grouse (Centrocercus urophasianus), a species of major conservation concern in shrub-steppe habitats. Thus, the urgent challenge for land management agencies in western North America is to identify bat day roost and foraging sites in order to develop management guidelines to conserve bats and their critical habitats. The specific objective of this study was to identify habitat characteristics that are important to western long-eared myotis (Myotis evotis) during the reproductive season in western juniper woodland of central Oregon. I used radio telemetry to find day roost sites and investigate selection criteria for these sites by lactating female and male bats. I studied day roost site selection at three spatial scales: roost, plot, and home range. I found that females prefer to roost in rocks rather than in trees, whereas males did not display a preference towards either type of roost substrate. Bats that roosted in trees used primarily pre-settlement junipers (> 150 years old) with at least one cavity, and bats that roosted in rocks used primarily formations consisting on multiple boulders. More available roost sites within 17.8 m of a tree roost site (or within 5 m of a rock roost site) was associated with an increased likelihood that a particular tree or rock roost site was selected. Males selected rock roosts that had greater area of pre-settlement woodlands than shrub-steppe within a 1 km radius. These results suggest that roost site selection differs between lactating females and males and occurs at multiple spatial scales. Land management practices that retain pre-settlement trees during juniper removal treatments and protect areas with high densities of roost sites near water sources are likely to conserve or restore bat populations. I also estimated home range size and the maximum foraging range of bats. Estimates of mean home range size were the largest ever reported for western long-eared myotis and among the largest for any Myotis species so far studied in North America. The mean 95% home range size for lactating females was 205.85 ha (SE = 47.94) and for males was 424.2 ha (SE = 187.2). The mean maximum foraging range for lactating females was 933 m (SE = 284.9) and males was 1522 m (SE = 532.8). Estimates of mean home range size and maximum foraging range did not differ between lactating females and males; however, low statistical power likely precluded detecting a difference. Lastly, I examined habitat selection at two spatial scales, (1) home range selection on the landscape scale and (2) foraging habitat selection within the home range. The probability of a location being selected by either lactating female or male bats decreased with increasing distance from day roost sites and water sources. Lactating females selected pre-settlement woodlands more than shrub-steppe habitat during foraging, but avoided areas with > 20% tree canopy cover more than areas with no canopy cover at the landscape scale. Males selected areas with 0.1% to 10% tree canopy cover more than areas with no canopy cover at the home range scale. To maintain foraging habitat for M. evotis in the study area, pre-settlement woodlands that are located near roost sites and water sources should be managed for variable tree densities. Close

• 13. [Article] Juniper utilization : issues of chemistry and management

  Western juniper (Juniperus occidentalis) poses both a challenge and an opportunity for natural resource management in the rangelands of the northern Great Basin. The continued expansion of western juniper ...

  Citation × Citation Citation Abstract Copy Title: Juniper utilization : issues of chemistry and management Author: Swartley, D. Benjamin Western juniper (Juniperus occidentalis) poses both a challenge and an opportunity for natural resource management in the rangelands of the northern Great Basin. The continued expansion of western juniper on the rangelands of the interior Northwest will likely continue as there are currently no practical options for returning this area to a pre-settlement state. Range managers face declining economic resources from both private and public funds to carry out development goals. Because economic resources are scarce, an efficient method of juniper management is needed to sustain both ecosystem function and economic use. One method of efficient management would be to develop economic incentives for land owners to extract marketable products from juniper woodlands. These products could then pay for, or reduce the cost of, management activities such as juniper removal and native plant restoration. A promising avenue for the development of such products is the extraction of natural oils from juniper trees. Research was executed to isolate and identify a potentially useful natural compound from the heartwood of western juniper. This compound, Hinokiic acid, was previously unobserved in the heartwood oil of western juniper. Now that its presence has been confirmed, ideas for the possible uses of the oil can be explored. By itself, the development of new products from juniper cannot provide all of the tools needed for range managers to more efficiently manage this species. Methods to determine the possible outcomes of management activities on the juniper system would also be valuable. The juniper system is complex and research into its natural functions is ongoing. With published data gathered through previous studies, an organizational and predictive population model was constructed for a hypothetical western juniper population. This is a first effort to model such a plant population and is designed to serve as a basis for future study. Overall, this research provides an example of a framework for combining forest product development with ecosystem management. Title: Juniper utilization : issues of chemistry and management Author: Swartley, D. Benjamin Western juniper (Juniperus occidentalis) poses both a challenge and an opportunity for natural resource management in the rangelands of the northern Great Basin. The continued expansion of western juniper on the rangelands of the interior Northwest will likely continue as there are currently no practical options for returning this area to a pre-settlement state. Range managers face declining economic resources from both private and public funds to carry out development goals. Because economic resources are scarce, an efficient method of juniper management is needed to sustain both ecosystem function and economic use. One method of efficient management would be to develop economic incentives for land owners to extract marketable products from juniper woodlands. These products could then pay for, or reduce the cost of, management activities such as juniper removal and native plant restoration. A promising avenue for the development of such products is the extraction of natural oils from juniper trees. Research was executed to isolate and identify a potentially useful natural compound from the heartwood of western juniper. This compound, Hinokiic acid, was previously unobserved in the heartwood oil of western juniper. Now that its presence has been confirmed, ideas for the possible uses of the oil can be explored. By itself, the development of new products from juniper cannot provide all of the tools needed for range managers to more efficiently manage this species. Methods to determine the possible outcomes of management activities on the juniper system would also be valuable. The juniper system is complex and research into its natural functions is ongoing. With published data gathered through previous studies, an organizational and predictive population model was constructed for a hypothetical western juniper population. This is a first effort to model such a plant population and is designed to serve as a basis for future study. Overall, this research provides an example of a framework for combining forest product development with ecosystem management. Close

• 14. [Article] Establishing Design Values for Potential Utilization of Western Juniper as a Building Material

  Western juniper (Juniperus occidentalis) is a conifer that is native to Oregon, California, Washington, Nevada, and Idaho. Juniper is known to have highly decay resistant heartwood and is a popular choice ...

  Citation × Citation Citation Abstract Copy Title: Establishing Design Values for Potential Utilization of Western Juniper as a Building Material Author: Miyamoto, Byrne Western juniper (Juniperus occidentalis) is a conifer that is native to Oregon, California, Washington, Nevada, and Idaho. Juniper is known to have highly decay resistant heartwood and is a popular choice for finished furniture. With recent forest management practices over the past 100 years have resulted in an immense population increase in western juniper stands, transforming the grasslands/sagebrush into juniper forests. Landowners have been encouraged to cutback western juniper to restore grassland habitat, but there is no major market associated with juniper. This study assessed the strength and durability properties of western juniper in order to develop design values in collaboration with the West Coast Lumber Inspection Bureau (WCLIB). The data will be presented to American Lumber Standard Committee (ALSC) for inclusion in the National Design Specification. Design values assigned to western juniper will allow contractors to use this species in structural and non-structural applications, especially for State funded projects. Samples were harvested from three locations in eastern Oregon, one location in northeast California, and one location in southwest Idaho. Tests were performed according to procedures described in ASTM Standard D143 small-clear specimens for compression, bending, and shear. Average strength values were calculated and compared to similar wood species. Most properties were similar to those of other species, but modulus of elasticity was significantly lower. The differences between species might be attributed to cell wall structure and distribution of lignin in the cells. Design values for western juniper were calculated using the strength values following the ASTM Standard D245 procedure for establishing structural grades and related allowable properties for visually graded lumber. Durability of western juniper was assessed using laboratory decay tests, marine tests, and ground contact exposure. The long term marine durability and ground contact tests are still on going. The laboratory decay test indicated that western juniper heartwood was highly resistant to attack by brown and white rot fungi. Title: Establishing Design Values for Potential Utilization of Western Juniper as a Building Material Author: Miyamoto, Byrne Western juniper (Juniperus occidentalis) is a conifer that is native to Oregon, California, Washington, Nevada, and Idaho. Juniper is known to have highly decay resistant heartwood and is a popular choice for finished furniture. With recent forest management practices over the past 100 years have resulted in an immense population increase in western juniper stands, transforming the grasslands/sagebrush into juniper forests. Landowners have been encouraged to cutback western juniper to restore grassland habitat, but there is no major market associated with juniper. This study assessed the strength and durability properties of western juniper in order to develop design values in collaboration with the West Coast Lumber Inspection Bureau (WCLIB). The data will be presented to American Lumber Standard Committee (ALSC) for inclusion in the National Design Specification. Design values assigned to western juniper will allow contractors to use this species in structural and non-structural applications, especially for State funded projects. Samples were harvested from three locations in eastern Oregon, one location in northeast California, and one location in southwest Idaho. Tests were performed according to procedures described in ASTM Standard D143 small-clear specimens for compression, bending, and shear. Average strength values were calculated and compared to similar wood species. Most properties were similar to those of other species, but modulus of elasticity was significantly lower. The differences between species might be attributed to cell wall structure and distribution of lignin in the cells. Design values for western juniper were calculated using the strength values following the ASTM Standard D245 procedure for establishing structural grades and related allowable properties for visually graded lumber. Durability of western juniper was assessed using laboratory decay tests, marine tests, and ground contact exposure. The long term marine durability and ground contact tests are still on going. The laboratory decay test indicated that western juniper heartwood was highly resistant to attack by brown and white rot fungi. Close

• 15. [Article] Lateral Edge Connection and Withdrawal Capacity of Western Juniper

  Western juniper (Juniperus occidentalis) is a “native invasive” tree species in Eastern Oregon. It is extremely good at finding and consuming water in arid climates, which makes it difficult for other ...

  Citation × Citation Citation Abstract Copy Title: Lateral Edge Connection and Withdrawal Capacity of Western Juniper Author: Girod, Hayley E. Western juniper (Juniperus occidentalis) is a “native invasive” tree species in Eastern Oregon. It is extremely good at finding and consuming water in arid climates, which makes it difficult for other plant species, especially sagebrush and grasses to survive. Sagebrush and grasses are necessary for the survival of the sage grouse, a threatened species. There is much discussion about harvesting juniper trees to help alleviate the stresses the trees put on the sage grouse and water supply in Eastern Oregon. However, there is not much of a market for juniper wood. Part of the reason is that there are no design values for juniper available, making engineers and designers reluctant to choose juniper for structural applications. The goal of this project is to increase the amount of available information about juniper wood in order to encourage its use in structural applications. To contribute to this goal, this project evaluated the performance of connections involving Western juniper wood and other common wood-based building materials. The tests for this project will include edge lateral nail connection test as per ASTM D 1575, dowel bearing strength test as per ASTM D 5764, and withdrawal test as per ASTM D 1761. Following the testing, the data was analyzed and inferences were drawn about the performance of the species in these types of connections. The results were also evaluated against predictive design equations found in the National Design Specification. The result of this project will help form a material statistic on performance of connections involving western juniper. Western juniper can potentially be an economically important species for rural Eastern Oregon. However, lack of engineering design values for the species and a performance metric for connections impedes its acceptance in mainstream construction. The data obtained in this study suggests that NDS equations can adequately predict connection performance of juniper, provided the specific gravity is known. Title: Lateral Edge Connection and Withdrawal Capacity of Western Juniper Author: Girod, Hayley E. Western juniper (Juniperus occidentalis) is a “native invasive” tree species in Eastern Oregon. It is extremely good at finding and consuming water in arid climates, which makes it difficult for other plant species, especially sagebrush and grasses to survive. Sagebrush and grasses are necessary for the survival of the sage grouse, a threatened species. There is much discussion about harvesting juniper trees to help alleviate the stresses the trees put on the sage grouse and water supply in Eastern Oregon. However, there is not much of a market for juniper wood. Part of the reason is that there are no design values for juniper available, making engineers and designers reluctant to choose juniper for structural applications. The goal of this project is to increase the amount of available information about juniper wood in order to encourage its use in structural applications. To contribute to this goal, this project evaluated the performance of connections involving Western juniper wood and other common wood-based building materials. The tests for this project will include edge lateral nail connection test as per ASTM D 1575, dowel bearing strength test as per ASTM D 5764, and withdrawal test as per ASTM D 1761. Following the testing, the data was analyzed and inferences were drawn about the performance of the species in these types of connections. The results were also evaluated against predictive design equations found in the National Design Specification. The result of this project will help form a material statistic on performance of connections involving western juniper. Western juniper can potentially be an economically important species for rural Eastern Oregon. However, lack of engineering design values for the species and a performance metric for connections impedes its acceptance in mainstream construction. The data obtained in this study suggests that NDS equations can adequately predict connection performance of juniper, provided the specific gravity is known. Close

• 16. [Article] Western Juniper (Juniperus occidentalis) and invasive annual grass mapping in Eastern Oregon

  In 2011, the Institute for Natural Resources – Portland (INR) entered into an agreement with the Natural Resources Conservation Service through the Cooperative Ecosystem Study Unit to assist in evaluation ...

  Citation × Citation Citation Abstract Copy Title: Western Juniper (Juniperus occidentalis) and invasive annual grass mapping in Eastern Oregon Author: Nielsen, Eric, Noone, Matthew, Kagan, James S. In 2011, the Institute for Natural Resources – Portland (INR) entered into an agreement with the Natural Resources Conservation Service through the Cooperative Ecosystem Study Unit to assist in evaluation of a targeted watershed restoration area in central Oregon. The primary objective of the agreement was to use remote sensing methodologies and widely available data sets to establish baseline landscape conditions that could be utilized by land managers as a planning tool and a measure of restoration project treatment success. Products and analysis developed by INR included: 1) A juniper percent canopy cover map for about 20 million acres in eastern Oregon and a juniper canopy cover increase/decrease map for a 17-year time interval between 1994 and 2011; 2) An exploratory analysis examining the feasibility of utilizing historic aerial photos to map historic juniper conditions; 3) A paired watershed analysis in Wheeler county examining outcomes of recent management activities; and 4) An exotic invasive annual map for 4.3 million acres spanning selected weed prioritization areas. The project was focused on using innovative remote sensing methods to identify the areas with existing juniper and invasive species concentrations. The resulting maps were intended to provide land managers with a preliminary planning tool describing existing baseline conditions across the region to help evaluate the effectiveness of different restoration treatments and identify priority areas for treatments. Title: Western Juniper (Juniperus occidentalis) and invasive annual grass mapping in Eastern Oregon Author: Nielsen, Eric, Noone, Matthew, Kagan, James S. In 2011, the Institute for Natural Resources – Portland (INR) entered into an agreement with the Natural Resources Conservation Service through the Cooperative Ecosystem Study Unit to assist in evaluation of a targeted watershed restoration area in central Oregon. The primary objective of the agreement was to use remote sensing methodologies and widely available data sets to establish baseline landscape conditions that could be utilized by land managers as a planning tool and a measure of restoration project treatment success. Products and analysis developed by INR included: 1) A juniper percent canopy cover map for about 20 million acres in eastern Oregon and a juniper canopy cover increase/decrease map for a 17-year time interval between 1994 and 2011; 2) An exploratory analysis examining the feasibility of utilizing historic aerial photos to map historic juniper conditions; 3) A paired watershed analysis in Wheeler county examining outcomes of recent management activities; and 4) An exotic invasive annual map for 4.3 million acres spanning selected weed prioritization areas. The project was focused on using innovative remote sensing methods to identify the areas with existing juniper and invasive species concentrations. The resulting maps were intended to provide land managers with a preliminary planning tool describing existing baseline conditions across the region to help evaluate the effectiveness of different restoration treatments and identify priority areas for treatments. Close

• 17. [Article] Physiological ecology of western juniper (Juniperus occidentalis hook. subsp. occidentalis)

  Patterns and costs of root/shoot allocations, response to reductions of above and below-ground tissue and to fertilization with nitrate and ammonium, and seasonal courses of physiological processes were ...

  Citation × Citation Citation Abstract Copy Title: Physiological ecology of western juniper (Juniperus occidentalis hook. subsp. occidentalis) Author: Miller, Patricia M. Patterns and costs of root/shoot allocations, response to reductions of above and below-ground tissue and to fertilization with nitrate and ammonium, and seasonal courses of physiological processes were measured on juvenile, small-adult, and large-adult Juniperus occidentalis growing in the field under ambient environmental conditions in eastern Oregon. Adult foliage had the highest heat of combustion, nitrogen concentrations, and construction cost. Allocation patterns indicated a larger investment in resources to above than below-ground tissue. J. occidentalis allocated larger proportions of dry mass to foliage, to maximize photosynthetic capacity, and to roots, to optimize water and nutrient acquisition; this was accomplished through reduction of allocation to branches and trunk. Removing [approximately] 50% of the foliage increased rates of CO₂ assimilation but did not increase growth, improve water status, or increase nitrogen concentration of remaining foliage. Cutting lateral roots reduced physiological processes and quantum-use-efficiencies and water-use-efficiencies. Fertilization increased foliar nitrogen concentrations and reduced CO₂ assimilation, leaf conductance, and transpiration. Juniperus occidentalis appears to be adapted to the low, ambient levels of soil nitrate and does not preferentially utilize ammonium. Highest daily total assimilation occurred during July and August. Juveniles had significantly higher assimilation and transpiration per gram foliage than did small or large-adults. Juveniles had the tightest control over water loss, but were not more water-use-efficient than small-adults or large-adults. Soil drought affected conductance independent of plant water potentials or vapor pressure deficits. Branchlet elongation was greatest in June and July. Juveniles were more responsive to the changing environment that were small-adults or large adults. Title: Physiological ecology of western juniper (Juniperus occidentalis hook. subsp. occidentalis) Author: Miller, Patricia M. Patterns and costs of root/shoot allocations, response to reductions of above and below-ground tissue and to fertilization with nitrate and ammonium, and seasonal courses of physiological processes were measured on juvenile, small-adult, and large-adult Juniperus occidentalis growing in the field under ambient environmental conditions in eastern Oregon. Adult foliage had the highest heat of combustion, nitrogen concentrations, and construction cost. Allocation patterns indicated a larger investment in resources to above than below-ground tissue. J. occidentalis allocated larger proportions of dry mass to foliage, to maximize photosynthetic capacity, and to roots, to optimize water and nutrient acquisition; this was accomplished through reduction of allocation to branches and trunk. Removing [approximately] 50% of the foliage increased rates of CO₂ assimilation but did not increase growth, improve water status, or increase nitrogen concentration of remaining foliage. Cutting lateral roots reduced physiological processes and quantum-use-efficiencies and water-use-efficiencies. Fertilization increased foliar nitrogen concentrations and reduced CO₂ assimilation, leaf conductance, and transpiration. Juniperus occidentalis appears to be adapted to the low, ambient levels of soil nitrate and does not preferentially utilize ammonium. Highest daily total assimilation occurred during July and August. Juveniles had significantly higher assimilation and transpiration per gram foliage than did small or large-adults. Juveniles had the tightest control over water loss, but were not more water-use-efficient than small-adults or large-adults. Soil drought affected conductance independent of plant water potentials or vapor pressure deficits. Branchlet elongation was greatest in June and July. Juveniles were more responsive to the changing environment that were small-adults or large adults. Close

• 18. [Article] Restoration of Mountain Big Sagebrush Steppe Following Prescribed Burning to Control Western Juniper

  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: Restoration of Mountain Big Sagebrush Steppe Following Prescribed Burning to Control Western Juniper Author: Nafus, A. M., Davies, K. W., Madsen, M. D., Bates, Jonathan D. 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/267. Title: Restoration of Mountain Big Sagebrush Steppe Following Prescribed Burning to Control Western Juniper Author: Nafus, A. M., Davies, K. W., Madsen, M. D., Bates, Jonathan D. 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/267. Close

• 19. [Article] Biology, ecology, and management of western juniper (Juniperus occidentalis)

  Published June 2005. Reviewed July 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Biology, ecology, and management of western juniper (Juniperus occidentalis) Author: Oregon State University. Agricultural Experiment Station, Miller, Richard F. Published June 2005. Reviewed July 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Biology, ecology, and management of western juniper (Juniperus occidentalis) Author: Oregon State University. Agricultural Experiment Station, Miller, Richard F. Published June 2005. Reviewed July 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 20. [Article] Understanding names of Oregon trees

  Revised April 2012. Received May 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Understanding names of Oregon trees Author: Oregon State University. Extension Service, Leavengood, Scott A. Revised April 2012. Received May 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Understanding names of Oregon trees Author: Oregon State University. Extension Service, Leavengood, Scott A. Revised April 2012. Received May 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 21. [Article] Tree Cover Mapping for Assessing Greater Sage-Grouse Habitat in Eastern Oregon

  We used a predictive model to map canopy cover of vegetation over seven feet in height ("tall woody vegetation") at 30-meter resolution over nearly 29 million acres within and adjacent to the range of ...

  Citation × Citation Citation Abstract Copy Title: Tree Cover Mapping for Assessing Greater Sage-Grouse Habitat in Eastern Oregon Author: Nielsen, Eric M., Noone, Matthew D. Year: 2014 We used a predictive model to map canopy cover of vegetation over seven feet in height ("tall woody vegetation") at 30-meter resolution over nearly 29 million acres within and adjacent to the range of the greater sage-grouse in Oregon (Figure 1). Texture measures computed at various resolutions from color-infrared aerial photography provided the main source of predictor data used to produce the map. Canopy cover was treated as a categorical variable using six cover classes: absent (cover class C0), present at less than 4% (C1), 4 – 10% (C2), 10 – 20% (C3), 20 – 50% (C4), and 50% and over (C5). The map is referenced to conditions in the years 2011 and 2012. Although the specific target of the mapping was western juniper (Juniperus occidentalis), our reference data did not permit separating juniper from other tall woody vegetation during the predictive modeling process. The majority of the tall woody vegetation within the project area is western juniper. However, in high elevation regions, riparian, wetland, and residential areas, other vegetation is occasionally represented. The methodology discussed here produces raw modeled data. It is recommended that prior to use in most applications this raw tree cover product be additionally filtered or masked to eliminate false detections which often occur adjacent to agricultural areas and roads. For species-specific applications, an additional modeling phase is necessary to either eliminate tree cover detections likely to be species other than the target, or to model species importance values associated with each tree occurrence. Title: Tree Cover Mapping for Assessing Greater Sage-Grouse Habitat in Eastern Oregon Author: Nielsen, Eric M., Noone, Matthew D. Year: 2014 We used a predictive model to map canopy cover of vegetation over seven feet in height ("tall woody vegetation") at 30-meter resolution over nearly 29 million acres within and adjacent to the range of the greater sage-grouse in Oregon (Figure 1). Texture measures computed at various resolutions from color-infrared aerial photography provided the main source of predictor data used to produce the map. Canopy cover was treated as a categorical variable using six cover classes: absent (cover class C0), present at less than 4% (C1), 4 – 10% (C2), 10 – 20% (C3), 20 – 50% (C4), and 50% and over (C5). The map is referenced to conditions in the years 2011 and 2012. Although the specific target of the mapping was western juniper (Juniperus occidentalis), our reference data did not permit separating juniper from other tall woody vegetation during the predictive modeling process. The majority of the tall woody vegetation within the project area is western juniper. However, in high elevation regions, riparian, wetland, and residential areas, other vegetation is occasionally represented. The methodology discussed here produces raw modeled data. It is recommended that prior to use in most applications this raw tree cover product be additionally filtered or masked to eliminate false detections which often occur adjacent to agricultural areas and roads. For species-specific applications, an additional modeling phase is necessary to either eliminate tree cover detections likely to be species other than the target, or to model species importance values associated with each tree occurrence. Close

• 22. [Article] Paired watershed ecological analysis

  This study was designed to provide a physical and ecological analysis of paired watersheds in the semi-arid western juniper (Juniperus occidentalis) woodlands of Central Oregon. Instrumentation and monitoring ...

  Citation × Citation Citation Abstract Copy Title: Paired watershed ecological analysis Author: Fisher, Michael, (Michael Patrick), 1966- This study was designed to provide a physical and ecological analysis of paired watersheds in the semi-arid western juniper (Juniperus occidentalis) woodlands of Central Oregon. Instrumentation and monitoring was accomplished in Jensen and Mays watersheds as the preliminary portion of a longer term project. Instrumentation was designed to address changes in the erosional processes, hydrology, and vegetation on a watershed scale. Instrumentation was setup to assist in the comparison and calibration of water flow out of the watersheds. This information will be used in the long-term study in conjunction with the treatment of the western juniper overstory on one of the watersheds. Determination of the study area in each watershed required extensive reconnaissance with the assistance of aerial photos, topographic maps, and Geographic Information Systems (GIS). Mapping of the study areas was accomplished with GIS and Global Positioning Systems (GPS). Watersheds were paired according to specific characteristics that influence treatment effects. Flume types were chosen with respect to precipitation intensity and frequency with placement being more a function of watershed topography and channel morphology. Upland sedimentation and erosion measurement required intense acknowledgement of both abiotic as well as biotic characteristics. Analysis showed the watersheds to be similar in size, percent juniper, grass and bare soil cover, topography, and precipitation frequency and intensity. Differences were obtained relative to erosional processes, area of different soil types and channel discharge. Further monitoring and calibration should provide greater insight into the comparison of these components of the study. Title: Paired watershed ecological analysis Author: Fisher, Michael, (Michael Patrick), 1966- This study was designed to provide a physical and ecological analysis of paired watersheds in the semi-arid western juniper (Juniperus occidentalis) woodlands of Central Oregon. Instrumentation and monitoring was accomplished in Jensen and Mays watersheds as the preliminary portion of a longer term project. Instrumentation was designed to address changes in the erosional processes, hydrology, and vegetation on a watershed scale. Instrumentation was setup to assist in the comparison and calibration of water flow out of the watersheds. This information will be used in the long-term study in conjunction with the treatment of the western juniper overstory on one of the watersheds. Determination of the study area in each watershed required extensive reconnaissance with the assistance of aerial photos, topographic maps, and Geographic Information Systems (GIS). Mapping of the study areas was accomplished with GIS and Global Positioning Systems (GPS). Watersheds were paired according to specific characteristics that influence treatment effects. Flume types were chosen with respect to precipitation intensity and frequency with placement being more a function of watershed topography and channel morphology. Upland sedimentation and erosion measurement required intense acknowledgement of both abiotic as well as biotic characteristics. Analysis showed the watersheds to be similar in size, percent juniper, grass and bare soil cover, topography, and precipitation frequency and intensity. Differences were obtained relative to erosional processes, area of different soil types and channel discharge. Further monitoring and calibration should provide greater insight into the comparison of these components of the study. Close

• 23. [Article] Ecosystem Analysis of Wetland and Riparian Zone restoration at the Hart Mountain Antelope Refuge over Twenty Years

  Presentation entitled : Ecosystem Analysis of Wetland and Riparian Zone restoration at the Hart Mountain Antelope Refuge over Twenty Years / by Schyler Reis, Lisa Ellsworth and J. Boone Kauffman

  Citation × Citation Citation Abstract Copy Title: Ecosystem Analysis of Wetland and Riparian Zone restoration at the Hart Mountain Antelope Refuge over Twenty Years Author: Reis, Schyler Ainsworth Presentation entitled : Ecosystem Analysis of Wetland and Riparian Zone restoration at the Hart Mountain Antelope Refuge over Twenty Years / by Schyler Reis, Lisa Ellsworth and J. Boone Kauffman Title: Ecosystem Analysis of Wetland and Riparian Zone restoration at the Hart Mountain Antelope Refuge over Twenty Years Author: Reis, Schyler Ainsworth Presentation entitled : Ecosystem Analysis of Wetland and Riparian Zone restoration at the Hart Mountain Antelope Refuge over Twenty Years / by Schyler Reis, Lisa Ellsworth and J. Boone Kauffman Close

• 24. [Article] Long-term Ecohydrologic Response to Western Juniper (Juniperus occidentalis) Control in Semiarid Watersheds of Central Oregon : A Paired Watershed Study

  Rangelands span over 50% of the globe and approximately 70% of the United States. Although livestock production is an important use of rangelands, the benefits of rangelands are highly diverse. Humans ...

  Citation × Citation Citation Abstract Copy Title: Long-term Ecohydrologic Response to Western Juniper (Juniperus occidentalis) Control in Semiarid Watersheds of Central Oregon : A Paired Watershed Study Author: Ray, Grace L. Rangelands span over 50% of the globe and approximately 70% of the United States. Although livestock production is an important use of rangelands, the benefits of rangelands are highly diverse. Humans find intrinsic value in protecting these unique and variable landscapes for wildlife, vegetation, and recreation enthusiasts. Woodland plant encroachment has become a major concern for land management agencies and private landowners across the United States and many rangeland communities worldwide. Studies around the world are characterizing the effect that woody species may have on ecologic and hydrologic function, as well as the potential consequences of prolonged encroachment. This research is an addition to a central Oregon paired watershed study that began in 1993 as way of characterizing ecohydrologic effects of western juniper (Juniperus occidentalis) removal. The overarching goals of the study presented here were to: 1) Characterize vegetation-soil water interactions at the landscape scale; 2) Analyze long-term soil water and groundwater fluctuations for treated versus untreated watersheds; 3) Asses subsurface flow connections between upland watersheds and a downstream valley. A landscape-scale assessment (2014 - 2015) of shallow soil water content, for to top 12-cm of the soil profile, across both watersheds indicated the treated watershed as having a significantly higher (P < 0.05) mean value of soil water content for three (July, January, and May) out of five measurement periods (July, November 2014 and January, March, May 2015). The untreated watershed was 2% higher in March 2015, and no significant difference was found between the two sites in November 2014. Analysis of the structure of canopy cover (i.e. juniper dominated versus juniper removed) using linear regression models found juniper cover to be correlated with decreasing soil water content for three of five months, with the exception of the wettest months of March and May, when juniper canopy was correlated with increases in soil water content. Soil textural properties were also analyzed as an independent variable in the linear models, and clay content was found to be correlated with increases in soil water content during the three wettest months (January, March, and May) across both watersheds. The long-term (2004 - 2015) analysis of groundwater level and deep soil water content fluctuations showed there to be distinct seasonal and storm-event responses. Groundwater levels in the untreated watershed consistently displayed higher yearly maximum values when compared to the treated, however, groundwater levels in the treated watershed persisted longer into the dry out period. Similar findings were reported in relation to long-term soil water content where the untreated watershed often displayed higher maximum responses but declined back to dry status sooner than the treated watershed. Both watersheds responded to seasonal and storm-event precipitation through soil water content fluctuations in the deep soil profile and through groundwater level fluctuations. Precipitation event responses could be observed on the order of hours for the treated watershed and on the order of days for the untreated. Antecedent soil water content seemed to play a large role in the effectiveness of the storm events. Summer precipitation had little influence on the deeper soil profile and on groundwater response. This may be due to dryer antecedent soil conditions and flashy overland flow. Water content in the top measured soil profile, however, increased and stayed at high levels for up to two weeks following a summer precipitation event which yielded approximately 27 mm of rainfall. Soil water and groundwater response were greatly influenced by winter precipitation events and pre-storm soil water conditions. The hydrologic connectivity of subsurface water flows, through fluctuations in deep soil water and groundwater levels, was found to be an important process in these watersheds. Temporary subsurface hydrologic connections were observed between upland and valley wells as the wet season progressed. This connection was supported by the results of a stable isotope analysis, which indicated that the origin of the water may be the same. This was concluded given the similar values of oxygen-18 found for both the treated and untreated upland sites and for valley groundwater monitoring locations. Large-scale juniper manipulation projects are taking place across the western United States and around the world. Many projects have the objectives of increasing water availability and stream flow to no avail. This research provides baseline data towards understanding the importance of the valuable subsurface water resources in landscapes with limited precipitation availability. Title: Long-term Ecohydrologic Response to Western Juniper (Juniperus occidentalis) Control in Semiarid Watersheds of Central Oregon : A Paired Watershed Study Author: Ray, Grace L. Rangelands span over 50% of the globe and approximately 70% of the United States. Although livestock production is an important use of rangelands, the benefits of rangelands are highly diverse. Humans find intrinsic value in protecting these unique and variable landscapes for wildlife, vegetation, and recreation enthusiasts. Woodland plant encroachment has become a major concern for land management agencies and private landowners across the United States and many rangeland communities worldwide. Studies around the world are characterizing the effect that woody species may have on ecologic and hydrologic function, as well as the potential consequences of prolonged encroachment. This research is an addition to a central Oregon paired watershed study that began in 1993 as way of characterizing ecohydrologic effects of western juniper (Juniperus occidentalis) removal. The overarching goals of the study presented here were to: 1) Characterize vegetation-soil water interactions at the landscape scale; 2) Analyze long-term soil water and groundwater fluctuations for treated versus untreated watersheds; 3) Asses subsurface flow connections between upland watersheds and a downstream valley. A landscape-scale assessment (2014 - 2015) of shallow soil water content, for to top 12-cm of the soil profile, across both watersheds indicated the treated watershed as having a significantly higher (P < 0.05) mean value of soil water content for three (July, January, and May) out of five measurement periods (July, November 2014 and January, March, May 2015). The untreated watershed was 2% higher in March 2015, and no significant difference was found between the two sites in November 2014. Analysis of the structure of canopy cover (i.e. juniper dominated versus juniper removed) using linear regression models found juniper cover to be correlated with decreasing soil water content for three of five months, with the exception of the wettest months of March and May, when juniper canopy was correlated with increases in soil water content. Soil textural properties were also analyzed as an independent variable in the linear models, and clay content was found to be correlated with increases in soil water content during the three wettest months (January, March, and May) across both watersheds. The long-term (2004 - 2015) analysis of groundwater level and deep soil water content fluctuations showed there to be distinct seasonal and storm-event responses. Groundwater levels in the untreated watershed consistently displayed higher yearly maximum values when compared to the treated, however, groundwater levels in the treated watershed persisted longer into the dry out period. Similar findings were reported in relation to long-term soil water content where the untreated watershed often displayed higher maximum responses but declined back to dry status sooner than the treated watershed. Both watersheds responded to seasonal and storm-event precipitation through soil water content fluctuations in the deep soil profile and through groundwater level fluctuations. Precipitation event responses could be observed on the order of hours for the treated watershed and on the order of days for the untreated. Antecedent soil water content seemed to play a large role in the effectiveness of the storm events. Summer precipitation had little influence on the deeper soil profile and on groundwater response. This may be due to dryer antecedent soil conditions and flashy overland flow. Water content in the top measured soil profile, however, increased and stayed at high levels for up to two weeks following a summer precipitation event which yielded approximately 27 mm of rainfall. Soil water and groundwater response were greatly influenced by winter precipitation events and pre-storm soil water conditions. The hydrologic connectivity of subsurface water flows, through fluctuations in deep soil water and groundwater levels, was found to be an important process in these watersheds. Temporary subsurface hydrologic connections were observed between upland and valley wells as the wet season progressed. This connection was supported by the results of a stable isotope analysis, which indicated that the origin of the water may be the same. This was concluded given the similar values of oxygen-18 found for both the treated and untreated upland sites and for valley groundwater monitoring locations. Large-scale juniper manipulation projects are taking place across the western United States and around the world. Many projects have the objectives of increasing water availability and stream flow to no avail. This research provides baseline data towards understanding the importance of the valuable subsurface water resources in landscapes with limited precipitation availability. Close

• 25. [Article] Vegetation and Small Mammal Responses to Western Juniper (Juniperus occidentalis) Control in Eastern Oregon

  Shrub-steppe ecosystems of western North America provide habitat for many wildlife species, are important components of public and private rangelands, and offer recreational opportunities for millions ...

  Citation × Citation Citation Abstract Copy Title: Vegetation and Small Mammal Responses to Western Juniper (Juniperus occidentalis) Control in Eastern Oregon Author: Morozumi, Corinne N. Shrub-steppe ecosystems of western North America provide habitat for many wildlife species, are important components of public and private rangelands, and offer recreational opportunities for millions of people. They are some of the most vulnerable ecosystems in the United States and have been altered by human activities such as livestock grazing, active fire suppression, conversion to agriculture, and urbanization of the west. Since the late 1800s woody encroachment of piñon-juniper species has also contributed to the loss of shrub-steppe habitat. Presently, land managers remove woody tree species in order to recover shrub-steppe although it is unclear how responses to these management activities differ due to site-specific conditions and existing woodland development. I studied post juniper-thinning responses in eastern Oregon at a wildlife area important as winter range for mule deer (Odocoileus hemionus). I investigated vegetative responses to western juniper (Juniperus occidentalis) thinning across a woodland development gradient and tested for interactive effects of juniper cutting and cattle exclusion. In addition, I explored plant and small mammal successional dynamics after juniper thinning and examined plant community responses within microhabitats created by the felled trees. I compared vegetative responses to juniper thinning as well as cattle exclusion among sites where juniper were subordinate (Phase I), co-dominant (Phase II), and dominant to shrubs and grasses (Phase III, sensu Miller et al. 2005). At the Phase I site, thinning did not increase herbaceous biomass while thinned plots at the Phase II site had 2.71 times more median herbaceous biomass (99.17% CI: 1.37 to 5.37 times more biomass) than unthinned plots. Conversely, herbaceous biomass at the Phase III juniper woodland site was 0.36 times lower in thinned plots when compared to unthinned plots (99.17% CI: 0.17 to 0.78 times less biomass). Unfortunately, many of the responses were driven by exotic species release. Where juniper were subordinate (Phase I), mean percent cover by exotic grass increased by 24.58 percentage points in thinned plots as compared to unthinned plots (98.30% CI: 0.27 to 48.90 percentage points higher). Thinning at the Phase II site increased mean exotic grass cover by an estimated 28.47 percentage points as compared to mean exotic cover in the same plots before treatment (98.30% CI: 4.15 to 52.79 percentage points higher cover). Median native bunchgrass cover at this site was 5.06 times greater after juniper treatment (99.7% CI: 1.78 to 14.35 times higher percent cover). I found few main or interactive effects of cattle exclosure after one year of treatment. Responses to grazing exclosure may take longer to develop. These results indicate that sites within the wildlife area respond differently to juniper management and that exotic grass control will be key to successful shrub-steppe recovery. In addition, I used a time-since-juniper thinning chronoseries consisting of plots cut in 2008, 2009, 2010, 2012, and an adjacent uncut control to explore how shrub-steppe flora and fauna are responding to juniper treatment through time. Shrub cover and seedling density were low in each plot. I recorded the highest seedling abundance (mean of 0.25 seedlings) in the uncut control plot. Median grass cover in the uncut control was 9.50% while in the most recently treated plot (2012) it was 26.75%. Small mammal relative abundance and diversity was low across all time-since-treatment plots though highest in the plot with the greatest time-since-treatment. Deer mouse (Peromyscus maniculatus) was the most abundant species in all plots and accounted for 70-95% of all unique captures. Least chipmunk (Tamias minimus) were present in the plot with greatest time-since-treatment indicating the potential recovery of key native shrubs since these small mammals perform an important seed dispersal role. I also investigated how potential microhabitats created by the felled juniper might support different plant communities. I assessed plant responses within zones created by 1) the felled tree (canopy zone), 2) the original duff zone, and 3) the between - tree interspace zone. The three zones had different plant community compositions as analyzed multivariately with non-metric multidimensional scaling (NMS). Canopy and duff zones were forb - dominated and had less exotic grass invasion while interspace zones were heavily invested with medusahead (Taeniatherum caput-medusae) and ventenata (Ventenata dubia). Exotic herbaceous productivity was lowest under the standing trees of the control plot and high in the interspace of all plots with juniper thinning. In the 2012 cut plot, grass cover was 27.90 percentage points less in the canopy zone compared to the interspace zone (98.75% CI: 17.64 to 38.16 percentage points less grass cover). In the uncut control, median native biomass was 2.08 times greater under the standing trees compared to the interspace (96.25% CI: 1.09 to 3.97 times more biomass). Results from the time-since-treatment chronoseries indicated that exotic grass dominance might be limiting shrub-steppe recovery. Active restoration of shrubs and native grasses may be necessary to address the dominance of exotic grass after juniper thinning. Positive signs of habitat recovery included small mammal responses though I was unable to calculate population estimates due to plot size. Title: Vegetation and Small Mammal Responses to Western Juniper (Juniperus occidentalis) Control in Eastern Oregon Author: Morozumi, Corinne N. Shrub-steppe ecosystems of western North America provide habitat for many wildlife species, are important components of public and private rangelands, and offer recreational opportunities for millions of people. They are some of the most vulnerable ecosystems in the United States and have been altered by human activities such as livestock grazing, active fire suppression, conversion to agriculture, and urbanization of the west. Since the late 1800s woody encroachment of piñon-juniper species has also contributed to the loss of shrub-steppe habitat. Presently, land managers remove woody tree species in order to recover shrub-steppe although it is unclear how responses to these management activities differ due to site-specific conditions and existing woodland development. I studied post juniper-thinning responses in eastern Oregon at a wildlife area important as winter range for mule deer (Odocoileus hemionus). I investigated vegetative responses to western juniper (Juniperus occidentalis) thinning across a woodland development gradient and tested for interactive effects of juniper cutting and cattle exclusion. In addition, I explored plant and small mammal successional dynamics after juniper thinning and examined plant community responses within microhabitats created by the felled trees. I compared vegetative responses to juniper thinning as well as cattle exclusion among sites where juniper were subordinate (Phase I), co-dominant (Phase II), and dominant to shrubs and grasses (Phase III, sensu Miller et al. 2005). At the Phase I site, thinning did not increase herbaceous biomass while thinned plots at the Phase II site had 2.71 times more median herbaceous biomass (99.17% CI: 1.37 to 5.37 times more biomass) than unthinned plots. Conversely, herbaceous biomass at the Phase III juniper woodland site was 0.36 times lower in thinned plots when compared to unthinned plots (99.17% CI: 0.17 to 0.78 times less biomass). Unfortunately, many of the responses were driven by exotic species release. Where juniper were subordinate (Phase I), mean percent cover by exotic grass increased by 24.58 percentage points in thinned plots as compared to unthinned plots (98.30% CI: 0.27 to 48.90 percentage points higher). Thinning at the Phase II site increased mean exotic grass cover by an estimated 28.47 percentage points as compared to mean exotic cover in the same plots before treatment (98.30% CI: 4.15 to 52.79 percentage points higher cover). Median native bunchgrass cover at this site was 5.06 times greater after juniper treatment (99.7% CI: 1.78 to 14.35 times higher percent cover). I found few main or interactive effects of cattle exclosure after one year of treatment. Responses to grazing exclosure may take longer to develop. These results indicate that sites within the wildlife area respond differently to juniper management and that exotic grass control will be key to successful shrub-steppe recovery. In addition, I used a time-since-juniper thinning chronoseries consisting of plots cut in 2008, 2009, 2010, 2012, and an adjacent uncut control to explore how shrub-steppe flora and fauna are responding to juniper treatment through time. Shrub cover and seedling density were low in each plot. I recorded the highest seedling abundance (mean of 0.25 seedlings) in the uncut control plot. Median grass cover in the uncut control was 9.50% while in the most recently treated plot (2012) it was 26.75%. Small mammal relative abundance and diversity was low across all time-since-treatment plots though highest in the plot with the greatest time-since-treatment. Deer mouse (Peromyscus maniculatus) was the most abundant species in all plots and accounted for 70-95% of all unique captures. Least chipmunk (Tamias minimus) were present in the plot with greatest time-since-treatment indicating the potential recovery of key native shrubs since these small mammals perform an important seed dispersal role. I also investigated how potential microhabitats created by the felled juniper might support different plant communities. I assessed plant responses within zones created by 1) the felled tree (canopy zone), 2) the original duff zone, and 3) the between - tree interspace zone. The three zones had different plant community compositions as analyzed multivariately with non-metric multidimensional scaling (NMS). Canopy and duff zones were forb - dominated and had less exotic grass invasion while interspace zones were heavily invested with medusahead (Taeniatherum caput-medusae) and ventenata (Ventenata dubia). Exotic herbaceous productivity was lowest under the standing trees of the control plot and high in the interspace of all plots with juniper thinning. In the 2012 cut plot, grass cover was 27.90 percentage points less in the canopy zone compared to the interspace zone (98.75% CI: 17.64 to 38.16 percentage points less grass cover). In the uncut control, median native biomass was 2.08 times greater under the standing trees compared to the interspace (96.25% CI: 1.09 to 3.97 times more biomass). Results from the time-since-treatment chronoseries indicated that exotic grass dominance might be limiting shrub-steppe recovery. Active restoration of shrubs and native grasses may be necessary to address the dominance of exotic grass after juniper thinning. Positive signs of habitat recovery included small mammal responses though I was unable to calculate population estimates due to plot size. Close

• 26. [Article] Spatial and temporal distributions of western juniper in John Day Fossil Beds National Monument, Oregon

  Post-settlement juniper expansion in the western states has been reported for decades, including western juniper (Juniperus occidentalis Hook ssp. occidentalis) woodlands in the northwestern states. A ...

  Citation × Citation Citation Abstract Copy Title: Spatial and temporal distributions of western juniper in John Day Fossil Beds National Monument, Oregon Author: Chen, Ya-Chian Post-settlement juniper expansion in the western states has been reported for decades, including western juniper (Juniperus occidentalis Hook ssp. occidentalis) woodlands in the northwestern states. A 15 km2 study area in the Sheep Rock Unit of John Day Fossil Beds National Monument in eastern Oregon was selected to study spatial and temporal distribution patterns of western junipers, and build statistical models for the patterns. Environmental characteristic data are from soil, vegetation and contour maps. Western juniper data are from aerial photos. Image processing techniques and geographical information system (GIS) were used to process data. Nonparametric statistical methods, including Kruskal-Wallis one-way analysis of variance by ranks, Spearman rank correlation coefficient, chi-square test and chi-square partitioning, and classification and regression tree (CART) were used for data analysis and building statistical models. The results show a clustering spatial distribution pattern. Western juniper is more abundant above elevations of about 900 to 1,000 meters MSL, on sites with soil type 15f- Gwin-Rock outcrop complex or 43f- Simas-Badlanci association, and on medium slopes, but probabilities of juniper occurrence on less steep slopes are higher at lower elevations. Northeastern aspects have significantly lower juniper abundances than other aspects. Junipers prefer sites with higher surface flow accumulation, except extremely high flow accumulation supporting only low juniper abundances. The CART spatial model shows three density classes classified by four out of five environmental characteristics with a misclassification rate of 0.27. Temporally, juniper density in the study area has increased from 37 junipers/ km2 to 1,404 junipers/ km2 during the last century. However, relationships of this expanding pattern to environmental characteristics are obscure. There is no conspicuous difference between habitats of young and old jumpers, except perhaps soil types. The likelihood for finding mature or old junipers is higher in sites with soil type 41e- Simas very stony clay loani, 43f- Simas-Badland association or 46f- Snell-Anatone complex. The spatioteniporal distribution pattern of western juniper in the study area could be described as a clustering pattern with chronologically increased abundances. Juniper may continue to increase its abundance and expand from high density areas to low density or non-juniper areas. Unless juniper density is controlled, it seems likely that junipers will dominate most of the monument's landscape in the future. Title: Spatial and temporal distributions of western juniper in John Day Fossil Beds National Monument, Oregon Author: Chen, Ya-Chian Post-settlement juniper expansion in the western states has been reported for decades, including western juniper (Juniperus occidentalis Hook ssp. occidentalis) woodlands in the northwestern states. A 15 km2 study area in the Sheep Rock Unit of John Day Fossil Beds National Monument in eastern Oregon was selected to study spatial and temporal distribution patterns of western junipers, and build statistical models for the patterns. Environmental characteristic data are from soil, vegetation and contour maps. Western juniper data are from aerial photos. Image processing techniques and geographical information system (GIS) were used to process data. Nonparametric statistical methods, including Kruskal-Wallis one-way analysis of variance by ranks, Spearman rank correlation coefficient, chi-square test and chi-square partitioning, and classification and regression tree (CART) were used for data analysis and building statistical models. The results show a clustering spatial distribution pattern. Western juniper is more abundant above elevations of about 900 to 1,000 meters MSL, on sites with soil type 15f- Gwin-Rock outcrop complex or 43f- Simas-Badlanci association, and on medium slopes, but probabilities of juniper occurrence on less steep slopes are higher at lower elevations. Northeastern aspects have significantly lower juniper abundances than other aspects. Junipers prefer sites with higher surface flow accumulation, except extremely high flow accumulation supporting only low juniper abundances. The CART spatial model shows three density classes classified by four out of five environmental characteristics with a misclassification rate of 0.27. Temporally, juniper density in the study area has increased from 37 junipers/ km2 to 1,404 junipers/ km2 during the last century. However, relationships of this expanding pattern to environmental characteristics are obscure. There is no conspicuous difference between habitats of young and old jumpers, except perhaps soil types. The likelihood for finding mature or old junipers is higher in sites with soil type 41e- Simas very stony clay loani, 43f- Simas-Badland association or 46f- Snell-Anatone complex. The spatioteniporal distribution pattern of western juniper in the study area could be described as a clustering pattern with chronologically increased abundances. Juniper may continue to increase its abundance and expand from high density areas to low density or non-juniper areas. Unless juniper density is controlled, it seems likely that junipers will dominate most of the monument's landscape in the future. Close

• 27. [Article] The influence of environmental attributes on temporal and structural dynamics of western juniper woodland development and associated fuel loading characteristics

  Since European American settlement of the Intermountain Region, dramatic changes in vegetation composition and structure have occurred in the sagebrush steppe ecosystem. Western juniper (Juniperus occidentalis ...

  Citation × Citation Citation Abstract Copy Title: The influence of environmental attributes on temporal and structural dynamics of western juniper woodland development and associated fuel loading characteristics Author: Johnson, Dustin D. Since European American settlement of the Intermountain Region, dramatic changes in vegetation composition and structure have occurred in the sagebrush steppe ecosystem. Western juniper (Juniperus occidentalis spp. occidentalis Vasek), although indigenous to the Intermountain Region, has increased since the late 1800s. Considerable work has been done documenting juniper woodland expansion in the Intermountain West, however, little is known about the environmental variables that influence rates of tree establishment and structural attributes of woodlands across landscapes. Most studies of western juniper have addressed site-specific questions at limited spatial scales. Consequently, there is a lack of research on broader scale patterns of woodland development occurring across heterogeneous landscapes. In addition, changes in the amount, composition, and structure of fuels during the transition from open sagebrush steppe communities to closed juniper woodlands have profound influences on the size, intensity, frequency, and behavior of fire. However, limited data exist quantifying changes in fuels during this transition, thus, consequences to fire behavior have been difficult to predict. The major impetus for the study was to determine the influence of environmental variables on rates and structural attributes of woodland development and associated changes in fuel loading characteristics during the transition from sagebrush steppe communities to closed juniper woodlands in the High Desert and Humboldt ecological provinces. The proportion of trees greater than 150 years old relative to trees less than 150 years suggest western juniper has greatly expanded in the Owyhee Mountains and on Steens Mountain since settlement of the areas. Ninety-five percent of the trees established after the 1850s. As evidenced by the presence of western juniper in 96% of plots sampled in this study, juniper is able to encroach upon a variety of plant alliances and under a broad range of environmental conditions over diverse landscapes. Although it appears the occurrence of western juniper within the woodland belt is not spatially limited by environmental or vegetative conditions, stand structural and fuel loading characteristics do vary considerably across heterogeneous landscapes. Total juniper density, density of dominant trees comprising the primary canopy, and certain live and dead fuels biomass very substantially with site potential. Spatial variation in stand structure and fuels may have significant implications to management of juniper at the landscape scale. Title: The influence of environmental attributes on temporal and structural dynamics of western juniper woodland development and associated fuel loading characteristics Author: Johnson, Dustin D. Since European American settlement of the Intermountain Region, dramatic changes in vegetation composition and structure have occurred in the sagebrush steppe ecosystem. Western juniper (Juniperus occidentalis spp. occidentalis Vasek), although indigenous to the Intermountain Region, has increased since the late 1800s. Considerable work has been done documenting juniper woodland expansion in the Intermountain West, however, little is known about the environmental variables that influence rates of tree establishment and structural attributes of woodlands across landscapes. Most studies of western juniper have addressed site-specific questions at limited spatial scales. Consequently, there is a lack of research on broader scale patterns of woodland development occurring across heterogeneous landscapes. In addition, changes in the amount, composition, and structure of fuels during the transition from open sagebrush steppe communities to closed juniper woodlands have profound influences on the size, intensity, frequency, and behavior of fire. However, limited data exist quantifying changes in fuels during this transition, thus, consequences to fire behavior have been difficult to predict. The major impetus for the study was to determine the influence of environmental variables on rates and structural attributes of woodland development and associated changes in fuel loading characteristics during the transition from sagebrush steppe communities to closed juniper woodlands in the High Desert and Humboldt ecological provinces. The proportion of trees greater than 150 years old relative to trees less than 150 years suggest western juniper has greatly expanded in the Owyhee Mountains and on Steens Mountain since settlement of the areas. Ninety-five percent of the trees established after the 1850s. As evidenced by the presence of western juniper in 96% of plots sampled in this study, juniper is able to encroach upon a variety of plant alliances and under a broad range of environmental conditions over diverse landscapes. Although it appears the occurrence of western juniper within the woodland belt is not spatially limited by environmental or vegetative conditions, stand structural and fuel loading characteristics do vary considerably across heterogeneous landscapes. Total juniper density, density of dominant trees comprising the primary canopy, and certain live and dead fuels biomass very substantially with site potential. Spatial variation in stand structure and fuels may have significant implications to management of juniper at the landscape scale. Close

• 28. [Article] Estimating a juniper biomass supply from private rangelands : the impact of distance and biotic factors on costs

  Central Oregon has attracted attention as a potential location for a biomass industry based on a locally fixed source of western juniper (Juniperus occidentalis Hook) feedstock. This study identifies ...

  Citation × Citation Citation Abstract Copy Title: Estimating a juniper biomass supply from private rangelands : the impact of distance and biotic factors on costs Author: McCaulou, Jeff, C. Central Oregon has attracted attention as a potential location for a biomass industry based on a locally fixed source of western juniper (Juniperus occidentalis Hook) feedstock. This study identifies a supply of juniper from private lands to determine how much of the available juniper is economically supplied at alternative prices if a market were to develop. In light of the encroachment of juniper and its spillover costs, the potential benefits of removal may be multi-dimensional in terms of private benefits to landowners, as well as social benefits from water and habitat enhancement. At current density, juniper on these private lands has negative impacts that diminish biodiversity, reduce forage grass and tie up water resources to some degree. The difference in the value of cattle productivity resulting from the presence of juniper as well as any forgone net returns from the sale of juniper to the biofuel industry reflect the opportunity cost to the rancher. The supply curve for juniper as a biofuel source will shift in response to policy and economic factors. For example, the Oregon Biofuel Producer tax credit and a federal wildlife enhancement program augment the acre level harvest costs, and thus shift supply. In this research, the components of cost are estimated. The average total cost for extraction, processing, and transporting the entire quantity is estimated to be approximately $120 bdt⁻¹. On a per land acre basis the costs will vary by density. Because of limited road networks the available supply of juniper was limited by access --only 27 percent of the juniper acres on private rangelands. Thus in the absence of an improved road network, economically viable juniper to supply the biofuel market is limited. Given the relatively low prices being discussed by the industry, the feasibility of supplying juniper at a scale needed for a biofuel facility is unlikely. The potential increases in cattle production due to juniper removal could reduce costs by 20 percent, but this is not likely to substantially increase the quantities supplied. Other possible shifters of the supply curve for juniper include subsidies, technological improvements in harvesting, and road building. Title: Estimating a juniper biomass supply from private rangelands : the impact of distance and biotic factors on costs Author: McCaulou, Jeff, C. Central Oregon has attracted attention as a potential location for a biomass industry based on a locally fixed source of western juniper (Juniperus occidentalis Hook) feedstock. This study identifies a supply of juniper from private lands to determine how much of the available juniper is economically supplied at alternative prices if a market were to develop. In light of the encroachment of juniper and its spillover costs, the potential benefits of removal may be multi-dimensional in terms of private benefits to landowners, as well as social benefits from water and habitat enhancement. At current density, juniper on these private lands has negative impacts that diminish biodiversity, reduce forage grass and tie up water resources to some degree. The difference in the value of cattle productivity resulting from the presence of juniper as well as any forgone net returns from the sale of juniper to the biofuel industry reflect the opportunity cost to the rancher. The supply curve for juniper as a biofuel source will shift in response to policy and economic factors. For example, the Oregon Biofuel Producer tax credit and a federal wildlife enhancement program augment the acre level harvest costs, and thus shift supply. In this research, the components of cost are estimated. The average total cost for extraction, processing, and transporting the entire quantity is estimated to be approximately $120 bdt⁻¹. On a per land acre basis the costs will vary by density. Because of limited road networks the available supply of juniper was limited by access --only 27 percent of the juniper acres on private rangelands. Thus in the absence of an improved road network, economically viable juniper to supply the biofuel market is limited. Given the relatively low prices being discussed by the industry, the feasibility of supplying juniper at a scale needed for a biofuel facility is unlikely. The potential increases in cattle production due to juniper removal could reduce costs by 20 percent, but this is not likely to substantially increase the quantities supplied. Other possible shifters of the supply curve for juniper include subsidies, technological improvements in harvesting, and road building. Close

• 29. [Article] Spatial and age class analysis of managed western juniper (Juniperus occidentalis) woodlands in central Oregon

  Juniper is a native species to Oregon and confers ecological benefits to wildlife when it is at savannah and transitional densities. Its range and extent have fluctuated with climatic change, but the current ...

  Citation × Citation Citation Abstract Copy Title: Spatial and age class analysis of managed western juniper (Juniperus occidentalis) woodlands in central Oregon Author: Zophy, Kelley T. Juniper is a native species to Oregon and confers ecological benefits to wildlife when it is at savannah and transitional densities. Its range and extent have fluctuated with climatic change, but the current range expansion is unprecedented in its extent. The range expansion has been associated with the degradation of the sagebrush steppe ecosystem in central Oregon. In the past, attempts to restore the sagebrush-steppe from western juniper aforestation were motivated by the desire to improve forage quality. Currently western juniper management is wider in scope, encompassing social, ecological, and environmental objectives. Past research in the area of western juniper management focused extensively on the causes of western juniper aforestation, its impact on understory plant communities, soil and the water budget. Researchers have also explored multiple mechanisms for removing western juniper and have quantified resulting amelioration of ecosystem function. However little work has been done identifying topographical features or environmental conditions that may influence the density of western juniper woodlands and seedling reestablishment following the application of treatment regimes. This study used spatial modeling to explore the influence that elevation and direct incident radiance have on western juniper density and multivariate, nonparametric tools to identify relationships between topography, understory plant community and seedling reestablishment on managed sites. The study findings indicate that western juniper densities in central Oregon are influenced by topographical features in the landscape. The multivariate analysis revealed that seedling reestablishment is positively associated with the diversity of the understory plant community. The study also revealed that on almost all of the sites included in the study, western juniper seedling are reestablishing after treatment application. With the information generated in the study, managers have tools with which to assess the risk a region has to be dominated by western juniper woodlands. Managers can then efficiently allocate western juniper management resources by choosing to treat that sites that have both the greatest risk and the greatest capacity to meet their objectives. Title: Spatial and age class analysis of managed western juniper (Juniperus occidentalis) woodlands in central Oregon Author: Zophy, Kelley T. Juniper is a native species to Oregon and confers ecological benefits to wildlife when it is at savannah and transitional densities. Its range and extent have fluctuated with climatic change, but the current range expansion is unprecedented in its extent. The range expansion has been associated with the degradation of the sagebrush steppe ecosystem in central Oregon. In the past, attempts to restore the sagebrush-steppe from western juniper aforestation were motivated by the desire to improve forage quality. Currently western juniper management is wider in scope, encompassing social, ecological, and environmental objectives. Past research in the area of western juniper management focused extensively on the causes of western juniper aforestation, its impact on understory plant communities, soil and the water budget. Researchers have also explored multiple mechanisms for removing western juniper and have quantified resulting amelioration of ecosystem function. However little work has been done identifying topographical features or environmental conditions that may influence the density of western juniper woodlands and seedling reestablishment following the application of treatment regimes. This study used spatial modeling to explore the influence that elevation and direct incident radiance have on western juniper density and multivariate, nonparametric tools to identify relationships between topography, understory plant community and seedling reestablishment on managed sites. The study findings indicate that western juniper densities in central Oregon are influenced by topographical features in the landscape. The multivariate analysis revealed that seedling reestablishment is positively associated with the diversity of the understory plant community. The study also revealed that on almost all of the sites included in the study, western juniper seedling are reestablishing after treatment application. With the information generated in the study, managers have tools with which to assess the risk a region has to be dominated by western juniper woodlands. Managers can then efficiently allocate western juniper management resources by choosing to treat that sites that have both the greatest risk and the greatest capacity to meet their objectives. Close

• 30. [Article] Western juniper encroachment into aspen communities in the Northwest Great Basin

  In the Northwest Great Basin, aspen (Populus tremuloides) communities uniquely contribute to the biodiversity of a semi-arid, sagebrush-dominated landscape. In this same region, western juniper (Juniperus ...

  Citation × Citation Citation Abstract Copy Title: Western juniper encroachment into aspen communities in the Northwest Great Basin Author: Wall, Travis G. In the Northwest Great Basin, aspen (Populus tremuloides) communities uniquely contribute to the biodiversity of a semi-arid, sagebrush-dominated landscape. In this same region, western juniper (Juniperus occidentalis) is encroaching into aspen stands. This study determined the timing, extent, and some of the effects of this expansion. Aspen stands below 2,133 m elevation were sampled in northwest Nevada, northeast California, and southeast Oregon for density, canopy cover, age, stand structure, and recruitment of western juniper and aspen. Soils and tree litter from both species were collected to analyze the effects of western juniper in areas previously influenced by aspen. Additionally, two large aspen complexes in southeast Oregon were intensively aged to determine disturbance (fire) frequencies. Western juniper encroachment into aspen stands peaked from 1920 to 1939 with 77% of all juniper trees sampled establishing during this period. Five percent were greater than 100 years and none exceeded 145 years. Three-fourths of aspen stands sampled have established populations of western juniper. Twenty-three percent have a dominant canopy of western juniper. Twelve percent of aspen stands sampled were completely replaced by western juniper. Average density of western juniper was 1,573 trees per hectare of aspen. Seventy percent of aspen stands sampled had zero recruitment of new aspen. Within the study area aspen stands averaged 98 years old. Forty-eight percent of stands were greater than 100 years old. There was an inverse correlation between aspen canopy cover and western juniper canopy cover (r²=.80, p=.0001). Soils influenced by western juniper had a higher C:N ratio and pH; higher amounts of salts, lime, and sulfate; and lower amounts of magnesium, iron, copper, and manganese (p<.05). Aspen litter had a lower C:N ratio than western juniper litter (p<.05). Prior to 1870, the two major aspen complexes sampled had mean fire return intervals of 10 and 11 years. However, the most recent disturbance in either complex was 80 to 90 years ago. This lack of disturbance (fire) coupled with aspen stand decadence and low recruitment levels leaves aspen communities in the Northwest Great Basin vulnerable to western juniper encroachment and replacement. Title: Western juniper encroachment into aspen communities in the Northwest Great Basin Author: Wall, Travis G. In the Northwest Great Basin, aspen (Populus tremuloides) communities uniquely contribute to the biodiversity of a semi-arid, sagebrush-dominated landscape. In this same region, western juniper (Juniperus occidentalis) is encroaching into aspen stands. This study determined the timing, extent, and some of the effects of this expansion. Aspen stands below 2,133 m elevation were sampled in northwest Nevada, northeast California, and southeast Oregon for density, canopy cover, age, stand structure, and recruitment of western juniper and aspen. Soils and tree litter from both species were collected to analyze the effects of western juniper in areas previously influenced by aspen. Additionally, two large aspen complexes in southeast Oregon were intensively aged to determine disturbance (fire) frequencies. Western juniper encroachment into aspen stands peaked from 1920 to 1939 with 77% of all juniper trees sampled establishing during this period. Five percent were greater than 100 years and none exceeded 145 years. Three-fourths of aspen stands sampled have established populations of western juniper. Twenty-three percent have a dominant canopy of western juniper. Twelve percent of aspen stands sampled were completely replaced by western juniper. Average density of western juniper was 1,573 trees per hectare of aspen. Seventy percent of aspen stands sampled had zero recruitment of new aspen. Within the study area aspen stands averaged 98 years old. Forty-eight percent of stands were greater than 100 years old. There was an inverse correlation between aspen canopy cover and western juniper canopy cover (r²=.80, p=.0001). Soils influenced by western juniper had a higher C:N ratio and pH; higher amounts of salts, lime, and sulfate; and lower amounts of magnesium, iron, copper, and manganese (p<.05). Aspen litter had a lower C:N ratio than western juniper litter (p<.05). Prior to 1870, the two major aspen complexes sampled had mean fire return intervals of 10 and 11 years. However, the most recent disturbance in either complex was 80 to 90 years ago. This lack of disturbance (fire) coupled with aspen stand decadence and low recruitment levels leaves aspen communities in the Northwest Great Basin vulnerable to western juniper encroachment and replacement. Close

• 31. [Article] Climate-growth relationships of western juniper and ponderosa pine at the pine-woodland ecotone in southern Oregon

  Pinyon-juniper woodlands throughout the western U.S. have expanded rapidly following European settlement during the late 19th century. In central and eastern Oregon, western juniper (Juniperus occidentalis ...

  Citation × Citation Citation Abstract Copy Title: Climate-growth relationships of western juniper and ponderosa pine at the pine-woodland ecotone in southern Oregon Author: Knutson, Kevin C. Pinyon-juniper woodlands throughout the western U.S. have expanded rapidly following European settlement during the late 19th century. In central and eastern Oregon, western juniper (Juniperus occidentalis var. occidentalis Hook.) encroachment has been previously documented in the sagebrush steppe and upper elevation aspen communities. While these vegetation changes and dynamics have been extensively studied, the ability to accurately predict future effects on vegetation structure in response to climatic effects requires the identification of climatic factors that most directly regulate growth across variations in spatial features, particularly when future climate change is likely. I sought to address this problem at the pine-woodland ecotone using tree-ring data for western juniper and ponderosa pine (Pinus ponderosa Dougl. Ex Loud.) from the Fremont National Forest of central Oregon. Site and soil-derived growth chronologies for the period 1950 to 2000 were developed for both species using standard dendrochronological techniques at 17 sites within the Fremont National Forest stratified by elevation (1584 and 1865 meters). Analysis of the climatic relationship with site and soil-derived chronologies using correlation and linear regression revealed that, similar to previous studies in Oregon, radial growth in both species is highly dependent on winter-spring precipitation events that recharge growing-season soil water. Ordinations of site- and soil-derived chronology principal components (PCA) scores for both species identified distinct gradients in growth patterns related to elevation, slope, and soil infiltration class. Low elevation sites had reduced growth in the nine driest years during 1950-2000 compared to high elevation sites. Slope was also positively associated with the ratio of standardized growth in wet years to dry years (W:D), a measure of climate sensitivity. Tree growth of both species on coarse-textured soils with rapid infiltration rates was more climate-sensitive (higher values of W:D) and was also reduced during drought years when compared to other infiltration classes. These findings suggest potentially significant variation in growth responses to future climate changes across distinct local features at the pine-woodland ecotone. Juniper and pine radial growth at sites that feature poor water-holding capacities (i.e., low elevation, steep slopes, and coarse-textured soils) can be expected to be most sensitive to future drought and climate fluctuations in southern Oregon. Title: Climate-growth relationships of western juniper and ponderosa pine at the pine-woodland ecotone in southern Oregon Author: Knutson, Kevin C. Pinyon-juniper woodlands throughout the western U.S. have expanded rapidly following European settlement during the late 19th century. In central and eastern Oregon, western juniper (Juniperus occidentalis var. occidentalis Hook.) encroachment has been previously documented in the sagebrush steppe and upper elevation aspen communities. While these vegetation changes and dynamics have been extensively studied, the ability to accurately predict future effects on vegetation structure in response to climatic effects requires the identification of climatic factors that most directly regulate growth across variations in spatial features, particularly when future climate change is likely. I sought to address this problem at the pine-woodland ecotone using tree-ring data for western juniper and ponderosa pine (Pinus ponderosa Dougl. Ex Loud.) from the Fremont National Forest of central Oregon. Site and soil-derived growth chronologies for the period 1950 to 2000 were developed for both species using standard dendrochronological techniques at 17 sites within the Fremont National Forest stratified by elevation (1584 and 1865 meters). Analysis of the climatic relationship with site and soil-derived chronologies using correlation and linear regression revealed that, similar to previous studies in Oregon, radial growth in both species is highly dependent on winter-spring precipitation events that recharge growing-season soil water. Ordinations of site- and soil-derived chronology principal components (PCA) scores for both species identified distinct gradients in growth patterns related to elevation, slope, and soil infiltration class. Low elevation sites had reduced growth in the nine driest years during 1950-2000 compared to high elevation sites. Slope was also positively associated with the ratio of standardized growth in wet years to dry years (W:D), a measure of climate sensitivity. Tree growth of both species on coarse-textured soils with rapid infiltration rates was more climate-sensitive (higher values of W:D) and was also reduced during drought years when compared to other infiltration classes. These findings suggest potentially significant variation in growth responses to future climate changes across distinct local features at the pine-woodland ecotone. Juniper and pine radial growth at sites that feature poor water-holding capacities (i.e., low elevation, steep slopes, and coarse-textured soils) can be expected to be most sensitive to future drought and climate fluctuations in southern Oregon. Close

• 32. [Article] Watershed response to western juniper control

  Western juniper (Juniperus occidentalis) encroachment has been associated with increased soil loss and reduced infiltration resulting in the loss of native herbaceous plant communities and the bird and ...

  Citation × Citation Citation Abstract Copy Title: Watershed response to western juniper control Author: Deboodt, Timothy L. Western juniper (Juniperus occidentalis) encroachment has been associated with increased soil loss and reduced infiltration resulting in the loss of native herbaceous plant communities and the bird and animal species that rely on them. Hydrologically, however, change in water yield has been linked with the amount of annual precipitation a site received. Studies published in the 1970’s and 1980’s, suggest that a minimum 4500 mm (18 inches) of annual precipitation was necessary before an increase in water yield manifested itself following vegetation manipulation. In 1993, a paired watershed study was initiated in the Camp Creek drainage, a tributary of the Crooked River of central Oregon, to evaluate the impacts of cutting western juniper on the hydrologic function of those sites. The study involved a paired watershed approach using watersheds of approximately 110 hectares (270 acres) each to evaluate changes in a system’s water budget following the reduction of western juniper. The 30 year average annual precipitation for the area is 3500 mm (13.75) and during the study period, annual precipitation ranged from 80 percent to 129 percent of average. In 2005, following 12 years of pretreatment monitoring in the 2 watersheds (Mays and Jensen) all post-European aged juniper (juniper < 140 years of age) were cut from the treatment watershed (Mays). Analysis indicated that juniper reduction significantly increased late season spring flow by 225 percent (alpha > .05), increased days of recorded ground water by an average of 41 days (alpha > .05) and increased the relative availability of late season soil moisture at soil depths of .76 m (27 inches) (alpha > 0.1). Ephemeral channel flow did not show a predictable trend during 2 years of post treatment measurements. Channel flow is dependent on spring snow melt and severe summer thunderstorm activity. When winter soils were greater than 0 degrees Celsius (32 degrees F), the source of channel flow in Mays was observed to be seepage from the channel banks. Channel flow in Jensen appeared to be a result of rock forcing subsurface flows to the surface. Vegetative responses showed significant increases in perennial forb canopy cover (alpha > .01) and annual forb and annual grass basal cover (alpha > .05). Increases were also found in reduction of percent bare ground and increase in shrub cover, but were not significant. A statistically insignificant decrease in perennial grass cover was noted in the treated watershed however a large amount of reproductive culms were noted in the treated watershed in 2007 compared to the control watershed. Hillslope erosion and channel morphology showed no predictable trend following treatment. Inherent differences in channel morphology between the two watershed prior to treatment existed. This difference may be a product of the two channels being at different evolutionary or successional stages relative to each other and thus indicating that channel recovery would be different for each watershed. The Camp Creek project illustrated that for this system, managing vegetation for water yield may be obtainable at a much lower precipitation threshold than what was previously reported in the literature. Title: Watershed response to western juniper control Author: Deboodt, Timothy L. Western juniper (Juniperus occidentalis) encroachment has been associated with increased soil loss and reduced infiltration resulting in the loss of native herbaceous plant communities and the bird and animal species that rely on them. Hydrologically, however, change in water yield has been linked with the amount of annual precipitation a site received. Studies published in the 1970’s and 1980’s, suggest that a minimum 4500 mm (18 inches) of annual precipitation was necessary before an increase in water yield manifested itself following vegetation manipulation. In 1993, a paired watershed study was initiated in the Camp Creek drainage, a tributary of the Crooked River of central Oregon, to evaluate the impacts of cutting western juniper on the hydrologic function of those sites. The study involved a paired watershed approach using watersheds of approximately 110 hectares (270 acres) each to evaluate changes in a system’s water budget following the reduction of western juniper. The 30 year average annual precipitation for the area is 3500 mm (13.75) and during the study period, annual precipitation ranged from 80 percent to 129 percent of average. In 2005, following 12 years of pretreatment monitoring in the 2 watersheds (Mays and Jensen) all post-European aged juniper (juniper < 140 years of age) were cut from the treatment watershed (Mays). Analysis indicated that juniper reduction significantly increased late season spring flow by 225 percent (alpha > .05), increased days of recorded ground water by an average of 41 days (alpha > .05) and increased the relative availability of late season soil moisture at soil depths of .76 m (27 inches) (alpha > 0.1). Ephemeral channel flow did not show a predictable trend during 2 years of post treatment measurements. Channel flow is dependent on spring snow melt and severe summer thunderstorm activity. When winter soils were greater than 0 degrees Celsius (32 degrees F), the source of channel flow in Mays was observed to be seepage from the channel banks. Channel flow in Jensen appeared to be a result of rock forcing subsurface flows to the surface. Vegetative responses showed significant increases in perennial forb canopy cover (alpha > .01) and annual forb and annual grass basal cover (alpha > .05). Increases were also found in reduction of percent bare ground and increase in shrub cover, but were not significant. A statistically insignificant decrease in perennial grass cover was noted in the treated watershed however a large amount of reproductive culms were noted in the treated watershed in 2007 compared to the control watershed. Hillslope erosion and channel morphology showed no predictable trend following treatment. Inherent differences in channel morphology between the two watershed prior to treatment existed. This difference may be a product of the two channels being at different evolutionary or successional stages relative to each other and thus indicating that channel recovery would be different for each watershed. The Camp Creek project illustrated that for this system, managing vegetation for water yield may be obtainable at a much lower precipitation threshold than what was previously reported in the literature. Close

• 33. [Article] Persistence of western juniper resource islands following canopy removal

  Western juniper (Juniperus occidentalis) cover has more than doubled within the last century and currently occupies over 9 million acres in the Intermountain West. Encroachment has altered the spatial ...

  Citation × Citation Citation Abstract Copy Title: Persistence of western juniper resource islands following canopy removal Author: Miwa, Christopher Western juniper (Juniperus occidentalis) cover has more than doubled within the last century and currently occupies over 9 million acres in the Intermountain West. Encroachment has altered the spatial distribution of soil nutrients and plants in these systems, forming nutrient enriched 'resource islands,' under tree canopies. The purpose of this study was to determine the persistence of resource island characteristics after restoration treatment (tree removal). The study site was a BLM grazing allotment in Eastern Oregon where trees had been cut 1, 8 and 15 years ago. In each age class and in uncut western juniper woodlands juniper stumps or trees were randomly selected for sampling. At each bole three radial transects, set at 120º from each other, were marked and soil cores were collected to 5-cm depth at distances of 50, 100, 150 and 300-cm from the bole then combined to a single composite sample per distance class. Samples were analyzed for total C and N, soluble P, K, Ca, Fe, Si, Al and Na, inorganic NH₄ and NO₃, pH and gravimetric water content. Fifteen years after canopy removal there was still strong evidence of western juniper resource islands. Canopy soils were generally significantly higher in Ctot, Ntot, NO₃‾, P, K and Ca compared to intercanopy soils in all treatments; however, accumulations for several elements appeared to degrade with time since canopy removal, and at different rates. We attribute resource island persistence to deep litter mats beneath relic canopies. Due to the strong zonal distribution of understory vegetation in juniper duff and bare zones these nutrient enriched areas will continue to influence long-term successional pathways and should be taken into account for restoration purposes, such as seeding of forbs and grasses. Title: Persistence of western juniper resource islands following canopy removal Author: Miwa, Christopher Western juniper (Juniperus occidentalis) cover has more than doubled within the last century and currently occupies over 9 million acres in the Intermountain West. Encroachment has altered the spatial distribution of soil nutrients and plants in these systems, forming nutrient enriched 'resource islands,' under tree canopies. The purpose of this study was to determine the persistence of resource island characteristics after restoration treatment (tree removal). The study site was a BLM grazing allotment in Eastern Oregon where trees had been cut 1, 8 and 15 years ago. In each age class and in uncut western juniper woodlands juniper stumps or trees were randomly selected for sampling. At each bole three radial transects, set at 120º from each other, were marked and soil cores were collected to 5-cm depth at distances of 50, 100, 150 and 300-cm from the bole then combined to a single composite sample per distance class. Samples were analyzed for total C and N, soluble P, K, Ca, Fe, Si, Al and Na, inorganic NH₄ and NO₃, pH and gravimetric water content. Fifteen years after canopy removal there was still strong evidence of western juniper resource islands. Canopy soils were generally significantly higher in Ctot, Ntot, NO₃‾, P, K and Ca compared to intercanopy soils in all treatments; however, accumulations for several elements appeared to degrade with time since canopy removal, and at different rates. We attribute resource island persistence to deep litter mats beneath relic canopies. Due to the strong zonal distribution of understory vegetation in juniper duff and bare zones these nutrient enriched areas will continue to influence long-term successional pathways and should be taken into account for restoration purposes, such as seeding of forbs and grasses. Close

• 34. [Article] Vegetation Response to Western Juniper Slash Treatments

  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: Vegetation Response to Western Juniper Slash Treatments Author: O’Connor, Casey, Bates, Jonathan D., Miller, Rick 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://www.springer.com/?SGWID=0-102-0-0-0. Title: Vegetation Response to Western Juniper Slash Treatments Author: O’Connor, Casey, Bates, Jonathan D., Miller, Rick 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://www.springer.com/?SGWID=0-102-0-0-0. Close

• 35. [Article] Effect of western juniper on understory herbage production in Central Oregon

  Evidence suggests that western juniper (Juniperus occidentalis) in Central Oregon affects understory production and composition. As trees increase in size and density, understory production is reduced ...

  Citation × Citation Citation Abstract Copy Title: Effect of western juniper on understory herbage production in Central Oregon Author: Vaitkus, Milda R. Evidence suggests that western juniper (Juniperus occidentalis) in Central Oregon affects understory production and composition. As trees increase in size and density, understory production is reduced and composition changes. This study was designed to identify the relationship between production and composition of understory vegetation and various tree canopy sizes of western juniper, and to describe the responses of understory vegetation to removal of western juniper. Understory production was sampled in 1983 and 1984 by clipping plots on an individual trees basis from areas with trees present and areas from which trees had been removed in 1982. Biomass production was determined from trees within three canopy diameter size classes and from two zones, beneath the canopy and in the interspace. Production was examined on two sites, a lower slope, shallow soil site and an upper slope, moderately deep soil site. Some year-to-year differences in production of individual species and specific tree sizes may be explained by variation in precipitation during critical growth periods the two years of the study. Sandberg bluegrass and, possibly, Idaho fescue production may have been greater in 1983 than 1984 due to variation in late spring precipitation, especially on shallow soils associated with small trees. Differences in patterns of production of individual species were most clearly developed associated with large, rather than small and intermediate trees. Cheatgrass, squirreltail, bluebunch wheatgrass, and Idaho fescue were common beneath the canopy, while Sandberg bluegrass was common in the interspaces. Cheatgrass and perennial forb production beneath the canopy increased with tree size. Production of other species, such as Sandberg bluegrass, was apparently not affected by tree size. Canopy removal resulted in species-specific increases in biomass production both years. Production increases were greater beneath the canopy than in the interspaces. Perennial grasses provided small variable production increases beneath the canopy of large trees. Annual grasses, primarily cheatgrass, and annual forbs, primarily Epilobium paniculatum, contributed most to elevated productivity the first two years following juniper removal. Cheatgrass response was mainly associated with large trees, while annual forb response was independent of tree size. Sandberg bluegrass production seemed more closely tied to growing season precipitation than to canopy removal, regardless of tree size. Title: Effect of western juniper on understory herbage production in Central Oregon Author: Vaitkus, Milda R. Evidence suggests that western juniper (Juniperus occidentalis) in Central Oregon affects understory production and composition. As trees increase in size and density, understory production is reduced and composition changes. This study was designed to identify the relationship between production and composition of understory vegetation and various tree canopy sizes of western juniper, and to describe the responses of understory vegetation to removal of western juniper. Understory production was sampled in 1983 and 1984 by clipping plots on an individual trees basis from areas with trees present and areas from which trees had been removed in 1982. Biomass production was determined from trees within three canopy diameter size classes and from two zones, beneath the canopy and in the interspace. Production was examined on two sites, a lower slope, shallow soil site and an upper slope, moderately deep soil site. Some year-to-year differences in production of individual species and specific tree sizes may be explained by variation in precipitation during critical growth periods the two years of the study. Sandberg bluegrass and, possibly, Idaho fescue production may have been greater in 1983 than 1984 due to variation in late spring precipitation, especially on shallow soils associated with small trees. Differences in patterns of production of individual species were most clearly developed associated with large, rather than small and intermediate trees. Cheatgrass, squirreltail, bluebunch wheatgrass, and Idaho fescue were common beneath the canopy, while Sandberg bluegrass was common in the interspaces. Cheatgrass and perennial forb production beneath the canopy increased with tree size. Production of other species, such as Sandberg bluegrass, was apparently not affected by tree size. Canopy removal resulted in species-specific increases in biomass production both years. Production increases were greater beneath the canopy than in the interspaces. Perennial grasses provided small variable production increases beneath the canopy of large trees. Annual grasses, primarily cheatgrass, and annual forbs, primarily Epilobium paniculatum, contributed most to elevated productivity the first two years following juniper removal. Cheatgrass response was mainly associated with large trees, while annual forb response was independent of tree size. Sandberg bluegrass production seemed more closely tied to growing season precipitation than to canopy removal, regardless of tree size. Close

• 36. [Article] Water limitations on forest carbon cycling and conifer traits along a steep climatic gradient in the Cascade Mountains, Oregon

  For a previous discussion paper please see: http://hdl.handle.net/1957/58002

  Citation × Citation Citation Abstract Copy Title: Water limitations on forest carbon cycling and conifer traits along a steep climatic gradient in the Cascade Mountains, Oregon Author: Law, B. E., Berner, L. T. For a previous discussion paper please see: http://hdl.handle.net/1957/58002 Title: Water limitations on forest carbon cycling and conifer traits along a steep climatic gradient in the Cascade Mountains, Oregon Author: Law, B. E., Berner, L. T. For a previous discussion paper please see: http://hdl.handle.net/1957/58002 Close

• 37. [Article] Water limitations on forest carbon cycling and conifer traits along a steep climatic gradient in the Cascade Mountains, Oregon

  The final revised paper is available at: http://hdl.handle.net/1957/58001

  Citation × Citation Citation Abstract Copy Title: Water limitations on forest carbon cycling and conifer traits along a steep climatic gradient in the Cascade Mountains, Oregon Author: Law, B. E., Berner, L. T. The final revised paper is available at: http://hdl.handle.net/1957/58001 Title: Water limitations on forest carbon cycling and conifer traits along a steep climatic gradient in the Cascade Mountains, Oregon Author: Law, B. E., Berner, L. T. The final revised paper is available at: http://hdl.handle.net/1957/58001 Close

• 38. [Article] Man and the land : an ecological history of fire and grazing on eastern Oregon rangelands

  Ecological and historical information are combined in examining the environmental influence of fire and grazing on rangelands in eastern Oregon through time. Competitive relationships between herbaceous ...

  Citation × Citation Citation Abstract Copy Title: Man and the land : an ecological history of fire and grazing on eastern Oregon rangelands Author: Shinn, Dean Allison Ecological and historical information are combined in examining the environmental influence of fire and grazing on rangelands in eastern Oregon through time. Competitive relationships between herbaceous and woody flora in the northern Great Basin are discussed, focusing broadly on the shrubsteppe regions 'of Franklin and Dyrness (1973) but with special reference to the Artemisia/Agropyron association. Impacts of native and domestic grazing animals and of cultural burning are traced from the distant past into recent history. During the Pleistocene Epoch North America supported a wide diversity of large mammals. Toward the end of the Pleistocene, many of these fauna became extinct, perhaps as a result of post-glacial climatic change, perhaps also under the influence of incoming primitive hunting cultures and their broadcast burning practices. Some question exists about the intensity of native grazing in the northern Great Basin during the last few thousand years. Actual levels of bison populations and the duration of their residence in the study area have not been determined. The character of indigenous vegetations, however, indicates that native grazing was relatively light for an extended period primevally. Twenty-four references to native cultural burning at the time of European contact were found in historical journals. Though the antiquity of these customs is uncertain, an analysis of Native American fire myths demonstrates the depth of native cultural perceptions of the relationship between man and fire, and supports the likelihood that fire was used primevally in the northern Great Basin as it was used by aboriginal peoples elsewhere in North America. With the influx of European culture during the 19th century, misapprehensions about fire among whites distorted the influence of native cultural burning. Exotic flora and fauna were introduced, and ecosystems began to change. Large herds of livestock depleted native herbaceous populations. Early irresponsible burning by whites became associated with declining rangeland resources, and efforts toward total fire suppression became incorporated in developing conservation policies. Native woody flora and exotics began to invade open rangeland communities. Climatic flux during the period of European settlement in the northern Great Basin may have exacerbated the impacts of intensified grazing and elimination of burning. Early photographs of rangelands in east-central Oregon were gathered; their dates range from 1880 to the early 1930's. Sites represented in these pictures were re-photographed in 1976. Photo-set comparisons show expansion of western juniper (Juniperus occidentalis) populations into rangeland ecosystems, demonstrating the consequences of cultural disturbances during the last 150 to 200 years. Title: Man and the land : an ecological history of fire and grazing on eastern Oregon rangelands Author: Shinn, Dean Allison Ecological and historical information are combined in examining the environmental influence of fire and grazing on rangelands in eastern Oregon through time. Competitive relationships between herbaceous and woody flora in the northern Great Basin are discussed, focusing broadly on the shrubsteppe regions 'of Franklin and Dyrness (1973) but with special reference to the Artemisia/Agropyron association. Impacts of native and domestic grazing animals and of cultural burning are traced from the distant past into recent history. During the Pleistocene Epoch North America supported a wide diversity of large mammals. Toward the end of the Pleistocene, many of these fauna became extinct, perhaps as a result of post-glacial climatic change, perhaps also under the influence of incoming primitive hunting cultures and their broadcast burning practices. Some question exists about the intensity of native grazing in the northern Great Basin during the last few thousand years. Actual levels of bison populations and the duration of their residence in the study area have not been determined. The character of indigenous vegetations, however, indicates that native grazing was relatively light for an extended period primevally. Twenty-four references to native cultural burning at the time of European contact were found in historical journals. Though the antiquity of these customs is uncertain, an analysis of Native American fire myths demonstrates the depth of native cultural perceptions of the relationship between man and fire, and supports the likelihood that fire was used primevally in the northern Great Basin as it was used by aboriginal peoples elsewhere in North America. With the influx of European culture during the 19th century, misapprehensions about fire among whites distorted the influence of native cultural burning. Exotic flora and fauna were introduced, and ecosystems began to change. Large herds of livestock depleted native herbaceous populations. Early irresponsible burning by whites became associated with declining rangeland resources, and efforts toward total fire suppression became incorporated in developing conservation policies. Native woody flora and exotics began to invade open rangeland communities. Climatic flux during the period of European settlement in the northern Great Basin may have exacerbated the impacts of intensified grazing and elimination of burning. Early photographs of rangelands in east-central Oregon were gathered; their dates range from 1880 to the early 1930's. Sites represented in these pictures were re-photographed in 1976. Photo-set comparisons show expansion of western juniper (Juniperus occidentalis) populations into rangeland ecosystems, demonstrating the consequences of cultural disturbances during the last 150 to 200 years. Close

• 39. [Article] Vegetation and soil response to tree removal methods in invasive western juniper woodlands

  On piñon-juniper encroached sites that lack the understory fuels to carry a prescribed fire, treatment options are limited to mechanical methods. Cutting with chainsaws and leaving the trees on site has ...

  Citation × Citation Citation Abstract Copy Title: Vegetation and soil response to tree removal methods in invasive western juniper woodlands Author: O'Connor, Casey A. On piñon-juniper encroached sites that lack the understory fuels to carry a prescribed fire, treatment options are limited to mechanical methods. Cutting with chainsaws and leaving the trees on site has been the primary treatment method for such sites, however this method creates a potential fire hazard, particularly in the first 2-3 years when needles remain suspended on downed trees. Follow-up treatments to remove juniper fuels, such as broadcast burning downed trees or moving slash into piles with machinery followed by burning are becoming more common practices on private and public lands. There is limited information on the impacts of mechanical and fire treatments on herbaceous recovery and impacts to soil nutrients and characteristics. It is important to evaluate these treatments to provide resource managers with ecological information to assist in developing appropriate fuel reduction measures. This study sampled herbaceous vegetation and soil attributes of three common mechanical treatments used to treat invasive western juniper (Juniperus occidentalis var. occidentalis Vasek) woodlands: Cut & Leave, Cut & Burn, and Pile & Burn. Sampling consisted of cover and density of herbaceous species and life forms (groups of species that function similarly), as well as total ground cover, and soil attributes including: carbon (C), nitrogen (N), carbon:nitrogen ratio (C:N), phosphorus (P), potassium (K), sulfate-sulfur (SO4-), calcium(Ca), magnesium (Mg), organic matter (OM~loss on ignition), cation exchange capacity (CEC), and power of hydrogen (pH). A randomized complete block experimental design (RCBD) was used with five 1-hectare blocks and three treatment plots per block (with piling plots being ½ hectare in size, and the other two treatment plots each ¼ hectare in size). Within each treatment plot, herbaceous vegetation sampling was stratified between three microsites: the slash microsite (beneath the three slash treatments; cut trees, burned trees, and burned piles), in the litter deposition microsite (litter zone around the stump) and the interspace microsite (between trees). Soil attributes were only sampled in the slash and interspace microsites, at two depths (0-4cm and 0-25cm). Each microsite within each plot was sampled by 40, 0.2m2 herbaceous frames and three composited soil samples from each depth. Mechanical treatments were completed in the fall of 2005 and prescribed fire treatments were completed in the fall of 2006. Treatment analysis compared pre and post treatment herbaceous data from 2005 and 2007, and soil attribute data from 2006 and 2007. Bare ground increased and litter and cover and density of most herbaceous species/life form groups declined beneath Cut & Burn and Pile & Burn treatments compared to the Cut & Leave treatment. The largest declines in cover and density of herbaceous species/life forms were recorded beneath burned piles. The largest changes measured adjacent to slash treatment locations (in the litter deposition and interspace microsites) were in the Cut & Burn plots due to fire spreading out burned trees. In the litter deposition microsite of the Cut & Burn treatment in 2007 total herbaceous cover was 1/3 and 1/2 that measured in the Cut & Leave and Pile & Burn plots, respectively. Contrarily the interspace microsite of the Cut & Burn treatment in 2007 indicated a slight (although insignificant) increase in herbaceous cover, with annual forb cover twice that measured in either of the other treatments. Concentrations of C, N, OM, and CEC were largely unchanged from pre-treatment levels in the compared treatments, however SO4, Mg, Ca, K, and pH all increased in response to burning compared to the Cut & Leave treatment. Implications of this research are limited to the first year post burn-treatment. However, these findings can be used as a general guide to choosing slash treatments to meet specific objectives. Determination of which of these treatments to use is largely dependent upon management objectives and site conditions. The high degree of vegetation disturbance and nutrient release measured beneath the Pile & Burn slash treatment could pose potential problems with invasive species establishment. However, the Cut & Burn treatment had similar, although less dramatic, vegetation disturbances and nutrient releases beneath burned slash, which covered a larger proportion of area than the Pile & Burn treatment. If a similar degree of invasive species establishment occurs in both of these slash burning treatments, the Pile & Burn treatment may be a better option due to the smaller area impacted. Measurements indicated little impact to vegetation in the Cut & Leave treatment, however wildfire risk could diminish the short term benefits of this treatment. Long term monitoring of herbaceous vegetation and soil attribute response among these three slash treatments is needed to make solid inferences of the site recovery following treatments to assist in land management decisions. Title: Vegetation and soil response to tree removal methods in invasive western juniper woodlands Author: O'Connor, Casey A. On piñon-juniper encroached sites that lack the understory fuels to carry a prescribed fire, treatment options are limited to mechanical methods. Cutting with chainsaws and leaving the trees on site has been the primary treatment method for such sites, however this method creates a potential fire hazard, particularly in the first 2-3 years when needles remain suspended on downed trees. Follow-up treatments to remove juniper fuels, such as broadcast burning downed trees or moving slash into piles with machinery followed by burning are becoming more common practices on private and public lands. There is limited information on the impacts of mechanical and fire treatments on herbaceous recovery and impacts to soil nutrients and characteristics. It is important to evaluate these treatments to provide resource managers with ecological information to assist in developing appropriate fuel reduction measures. This study sampled herbaceous vegetation and soil attributes of three common mechanical treatments used to treat invasive western juniper (Juniperus occidentalis var. occidentalis Vasek) woodlands: Cut & Leave, Cut & Burn, and Pile & Burn. Sampling consisted of cover and density of herbaceous species and life forms (groups of species that function similarly), as well as total ground cover, and soil attributes including: carbon (C), nitrogen (N), carbon:nitrogen ratio (C:N), phosphorus (P), potassium (K), sulfate-sulfur (SO4-), calcium(Ca), magnesium (Mg), organic matter (OM~loss on ignition), cation exchange capacity (CEC), and power of hydrogen (pH). A randomized complete block experimental design (RCBD) was used with five 1-hectare blocks and three treatment plots per block (with piling plots being ½ hectare in size, and the other two treatment plots each ¼ hectare in size). Within each treatment plot, herbaceous vegetation sampling was stratified between three microsites: the slash microsite (beneath the three slash treatments; cut trees, burned trees, and burned piles), in the litter deposition microsite (litter zone around the stump) and the interspace microsite (between trees). Soil attributes were only sampled in the slash and interspace microsites, at two depths (0-4cm and 0-25cm). Each microsite within each plot was sampled by 40, 0.2m2 herbaceous frames and three composited soil samples from each depth. Mechanical treatments were completed in the fall of 2005 and prescribed fire treatments were completed in the fall of 2006. Treatment analysis compared pre and post treatment herbaceous data from 2005 and 2007, and soil attribute data from 2006 and 2007. Bare ground increased and litter and cover and density of most herbaceous species/life form groups declined beneath Cut & Burn and Pile & Burn treatments compared to the Cut & Leave treatment. The largest declines in cover and density of herbaceous species/life forms were recorded beneath burned piles. The largest changes measured adjacent to slash treatment locations (in the litter deposition and interspace microsites) were in the Cut & Burn plots due to fire spreading out burned trees. In the litter deposition microsite of the Cut & Burn treatment in 2007 total herbaceous cover was 1/3 and 1/2 that measured in the Cut & Leave and Pile & Burn plots, respectively. Contrarily the interspace microsite of the Cut & Burn treatment in 2007 indicated a slight (although insignificant) increase in herbaceous cover, with annual forb cover twice that measured in either of the other treatments. Concentrations of C, N, OM, and CEC were largely unchanged from pre-treatment levels in the compared treatments, however SO4, Mg, Ca, K, and pH all increased in response to burning compared to the Cut & Leave treatment. Implications of this research are limited to the first year post burn-treatment. However, these findings can be used as a general guide to choosing slash treatments to meet specific objectives. Determination of which of these treatments to use is largely dependent upon management objectives and site conditions. The high degree of vegetation disturbance and nutrient release measured beneath the Pile & Burn slash treatment could pose potential problems with invasive species establishment. However, the Cut & Burn treatment had similar, although less dramatic, vegetation disturbances and nutrient releases beneath burned slash, which covered a larger proportion of area than the Pile & Burn treatment. If a similar degree of invasive species establishment occurs in both of these slash burning treatments, the Pile & Burn treatment may be a better option due to the smaller area impacted. Measurements indicated little impact to vegetation in the Cut & Leave treatment, however wildfire risk could diminish the short term benefits of this treatment. Long term monitoring of herbaceous vegetation and soil attribute response among these three slash treatments is needed to make solid inferences of the site recovery following treatments to assist in land management decisions. Close

• 40. [Image] A review of scientific information on issues related to the use and management of water resources in the Pacific Northwest

  	Abstract Everest, Fred H.; Stouder, Deanna J.; Kakoyannis, Christina; Houston, Laurie; Stankey, George; Kline, Jeffery; Alig, Ralph. 2004. A review of scientific information ...
  	Citation × Citation Citation Abstract Copy Title: A review of scientific information on issues related to the use and management of water resources in the Pacific Northwest Year: 2004 Abstract Everest, Fred H.; Stouder, Deanna J.; Kakoyannis, Christina; Houston, Laurie; Stankey, George; Kline, Jeffery; Alig, Ralph. 2004. A review of scientific information on issues related to the use and management of water resources in the Pacific Northwest. Gen. Tech. Rep. PNW-GTR-595. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 128 p. Fresh water is a valuable and essential commodity in the Pacific Northwest States, specifically Oregon, Washington, and Idaho, and one provided abundantly by forested watersheds in the region. The maintenance and growth of industrial, municipal, agricultural, and recreational activities in the region are dependent on adequate and sustainable supplies of fresh water from surface and ground-water sources. Future development, especially in the semiarid intermountain area, depends on the conservation and expansion of the region's water resource. This synthesis reviews the state of our knowledge and condition of water resources in the Pacific Northwest. Keywords: Water distribution, flow regimes, water demand, conflicts, tools, water use. Title: A review of scientific information on issues related to the use and management of water resources in the Pacific Northwest Year: 2004 Abstract Everest, Fred H.; Stouder, Deanna J.; Kakoyannis, Christina; Houston, Laurie; Stankey, George; Kline, Jeffery; Alig, Ralph. 2004. A review of scientific information on issues related to the use and management of water resources in the Pacific Northwest. Gen. Tech. Rep. PNW-GTR-595. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 128 p. Fresh water is a valuable and essential commodity in the Pacific Northwest States, specifically Oregon, Washington, and Idaho, and one provided abundantly by forested watersheds in the region. The maintenance and growth of industrial, municipal, agricultural, and recreational activities in the region are dependent on adequate and sustainable supplies of fresh water from surface and ground-water sources. Future development, especially in the semiarid intermountain area, depends on the conservation and expansion of the region's water resource. This synthesis reviews the state of our knowledge and condition of water resources in the Pacific Northwest. Keywords: Water distribution, flow regimes, water demand, conflicts, tools, water use. Close

• 41. [Article] Biomass Supply Curves for Western Juniper in Central Oregon, USA, Under Alternative Business Model and Policy Assumptions

  Access to this item has been restricted by repository administrators at the request of the publisher, Elsevier, until June 14, 2017.

  Citation × Citation Citation Abstract Copy Title: Biomass Supply Curves for Western Juniper in Central Oregon, USA, Under Alternative Business Model and Policy Assumptions Author: Capalbo, Susan M., McCaulou, Jeff C., Sessions, John, Lauer, Chris Access to this item has been restricted by repository administrators at the request of the publisher, Elsevier, until June 14, 2017. Title: Biomass Supply Curves for Western Juniper in Central Oregon, USA, Under Alternative Business Model and Policy Assumptions Author: Capalbo, Susan M., McCaulou, Jeff C., Sessions, John, Lauer, Chris Access to this item has been restricted by repository administrators at the request of the publisher, Elsevier, until June 14, 2017. Close

• 42. [Article] Seed bank response to juniper expansion in the semi-arid lands of Oregon, USA

  Expansion of Juniperus occidentalis into the sagebrush steppe has resulted in significant changes in understory composition. A consequence of increased J. occidentalis dominance may be a depletion of the ...

  Citation × Citation Citation Abstract Copy Title: Seed bank response to juniper expansion in the semi-arid lands of Oregon, USA Author: Duncan, Corinne M. Expansion of Juniperus occidentalis into the sagebrush steppe has resulted in significant changes in understory composition. A consequence of increased J. occidentalis dominance may be a depletion of the seed bank. The potential for depletion is problematic because a reduction in the amount of species available from the seed bank may compromise site resiliency. During disturbances that disrupt current vegetation, a reduction in recruitment from the seed bank could cause the site to be more vulnerable to colonization by weedy species or could lead to a reduction in the amount of cover protecting the soil surface and thus increase site susceptibility to erosion. This research evaluated the effects of the relative abundance of J. occidentalis on the soil seed bank. Questions addressed were: 1) is species richness negatively correlated with J. occidentalis cover; 2) does the diversity of weedy species increase along a gradient of J. occidentalis cover; and 3) does seed density decrease as J. occidentalis cover increases? We also attempted to identify seed bank depletion thresholds based on seed density. Two eastern Oregon sagebrush steppe sites where chosen to represent the juniper woodland-sagebrush steppe region. These sites displayed a range of J. occidentalis canopy cover. Soil and litter samples were collected in the fall of 2006 and 2007 and subjected to both cold-wet and warm-dry stratification. Germination occurred over a period of eight months under greenhouse conditions. Linear and Poisson regression techniques were used to evaluate relationships. A non-parametric deviance reduction approach was used for threshold detection and a threshold strength index was used to evaluate the strength of the identified thresholds. No statistically significant relationships were detected between J. occidentalis cover and species richness or weedy species diversity at either site in either year, with the exception of Bridge Creek in 2007 which showed a positive correlation between J. occidentalis cover and seed bank species diversity. The results for seed density were more complex. In 2006, J. occidentalis cover was strongly related to seed density at Devine Ridge but in 2007 there was no evidence of a correlation. At Bridge Creek in 2006, there was a weak relationship between increasing J. occidentalis cover and decreasing seed density but in the second year the pattern differed suggesting a positive correlation between J. occidentalis cover and seedling density. This variability in results suggests a complex relationship between J. occidentalis cover and seed bank composition. This relationship may partially depend on weather conditions, and a more lengthy study period would be valuable in discerning whether such a correlation exists. Concerning threshold detection, seed bank depletion thresholds were identified across both sites and years but their strength was very weak. These findings indicate that a reliable seed bank depletion threshold, as defined in this study, may not exist for these sites at least over the course of this study. Though these results were negative, the approach was useful and pursuit of its further development is suggested for evaluation of other suspected thresholds. Title: Seed bank response to juniper expansion in the semi-arid lands of Oregon, USA Author: Duncan, Corinne M. Expansion of Juniperus occidentalis into the sagebrush steppe has resulted in significant changes in understory composition. A consequence of increased J. occidentalis dominance may be a depletion of the seed bank. The potential for depletion is problematic because a reduction in the amount of species available from the seed bank may compromise site resiliency. During disturbances that disrupt current vegetation, a reduction in recruitment from the seed bank could cause the site to be more vulnerable to colonization by weedy species or could lead to a reduction in the amount of cover protecting the soil surface and thus increase site susceptibility to erosion. This research evaluated the effects of the relative abundance of J. occidentalis on the soil seed bank. Questions addressed were: 1) is species richness negatively correlated with J. occidentalis cover; 2) does the diversity of weedy species increase along a gradient of J. occidentalis cover; and 3) does seed density decrease as J. occidentalis cover increases? We also attempted to identify seed bank depletion thresholds based on seed density. Two eastern Oregon sagebrush steppe sites where chosen to represent the juniper woodland-sagebrush steppe region. These sites displayed a range of J. occidentalis canopy cover. Soil and litter samples were collected in the fall of 2006 and 2007 and subjected to both cold-wet and warm-dry stratification. Germination occurred over a period of eight months under greenhouse conditions. Linear and Poisson regression techniques were used to evaluate relationships. A non-parametric deviance reduction approach was used for threshold detection and a threshold strength index was used to evaluate the strength of the identified thresholds. No statistically significant relationships were detected between J. occidentalis cover and species richness or weedy species diversity at either site in either year, with the exception of Bridge Creek in 2007 which showed a positive correlation between J. occidentalis cover and seed bank species diversity. The results for seed density were more complex. In 2006, J. occidentalis cover was strongly related to seed density at Devine Ridge but in 2007 there was no evidence of a correlation. At Bridge Creek in 2006, there was a weak relationship between increasing J. occidentalis cover and decreasing seed density but in the second year the pattern differed suggesting a positive correlation between J. occidentalis cover and seedling density. This variability in results suggests a complex relationship between J. occidentalis cover and seed bank composition. This relationship may partially depend on weather conditions, and a more lengthy study period would be valuable in discerning whether such a correlation exists. Concerning threshold detection, seed bank depletion thresholds were identified across both sites and years but their strength was very weak. These findings indicate that a reliable seed bank depletion threshold, as defined in this study, may not exist for these sites at least over the course of this study. Though these results were negative, the approach was useful and pursuit of its further development is suggested for evaluation of other suspected thresholds. Close

• 43. [Article] Composition of the volatile oil from the foliage and terminal branches of Sierra juniper, Juniperus occidentalis, Hooker

  Citation × Citation Citation Abstract Copy Title: Composition of the volatile oil from the foliage and terminal branches of Sierra juniper, Juniperus occidentalis, Hooker Author: Fahey, Michael Duncan Title: Composition of the volatile oil from the foliage and terminal branches of Sierra juniper, Juniperus occidentalis, Hooker Author: Fahey, Michael Duncan Close

• 44. [Article] Fuel Reduction, Seeding, and Vegetation in a Juniper Woodland

  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 the Society ...

  Citation × Citation Citation Abstract Copy Title: Fuel Reduction, Seeding, and Vegetation in a Juniper Woodland Author: Day, M. A., Kerns, B. K. 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 the Society for Range Management and can be found at: http://www.bioone.org/loi/rama. Title: Fuel Reduction, Seeding, and Vegetation in a Juniper Woodland Author: Day, M. A., Kerns, B. K. 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 the Society for Range Management and can be found at: http://www.bioone.org/loi/rama. Close

• 45. [Article] Constituents of the petroleum ether extractive from Sierra juniper (Juniperus occidentalis, Hooker)

  Citation × Citation Citation Abstract Copy Title: Constituents of the petroleum ether extractive from Sierra juniper (Juniperus occidentalis, Hooker) Author: Lackey, Homer Baird Title: Constituents of the petroleum ether extractive from Sierra juniper (Juniperus occidentalis, Hooker) Author: Lackey, Homer Baird Close

• 46. [Article] The economics of western juniper management on ranches located in the John Day Ecological Province of north-central Oregon

  Western juniper (Jun iperus occidentalis Hook) is a species of juniper native to arid regions of the Pacific Northwest. The western juniper tree has a number of competitive strategies that, in conjunction ...

  Citation × Citation Citation Abstract Copy Title: The economics of western juniper management on ranches located in the John Day Ecological Province of north-central Oregon Author: Aldrich, Gwendolyn A. Western juniper (Jun iperus occidentalis Hook) is a species of juniper native to arid regions of the Pacific Northwest. The western juniper tree has a number of competitive strategies that, in conjunction with an almost complete removal of fire from the ecosystem, have resulted in a significant expansion of its population in the last 150 years. This increase is of concern since western juniper have numerous negative impacts on the ecosystems upon which they encroach. Western juniper can cause increased erosion, decreased production of herbaceous vegetation, decreased streamflows and increased stream sedimentation, increased bare ground, and changes in wildlife diversity and species abundance. However, because western juniper is both expensive and difficult to kill or harvest, and because there is a limited market for its wood and other western juniper products, the expansion of western juniper populations throughout parts of the Pacific Northwest occurs largely unimpeded. Within western juniper's range in central and eastern Oregon, much of the land is owned by and operated as beef cattle ranches. As western juniper encroach upon a site, the reduction in herbaceous vegetation causes a decrease in the number of livestock the site can support. As the ability of rangeland to support livestock declines, ranch profits will also likely diminish Despite this trend, clearing of western juniper has historically been limited. This research presents discrete-time, dynamic economic models developed to depict various representative ranches located in the John Day Ecological Province of Oregon, the area of the greatest distribution of western jumper and where the majority of research regarding the western juniper has been conducted. The bioeconomic models are developed to examine optimal ranch management practices. The optimization criterion is to maximize the net present value of gross margins through decisions regarding herd size and composition, cattle sales, and the manipulation of forage production through juniper management practices. Comparisons are made to models in which juniper control is not a management option. Results indicate that it is indeed profitable for ranchers to practice juniper management on rangeland pastures. Models that included juniper management options consistently resulted in treatment of a minimum of seventy percent of juniper-encroached rangelands, larger equilibrium herd sizes, and greater gross margins. Erosion levels, and therefore potential stream sedimentation, was substantially lower in the models that contained juniper management options. Other environmental externalities included increased quail densities, but lower deer and elk populations. Title: The economics of western juniper management on ranches located in the John Day Ecological Province of north-central Oregon Author: Aldrich, Gwendolyn A. Western juniper (Jun iperus occidentalis Hook) is a species of juniper native to arid regions of the Pacific Northwest. The western juniper tree has a number of competitive strategies that, in conjunction with an almost complete removal of fire from the ecosystem, have resulted in a significant expansion of its population in the last 150 years. This increase is of concern since western juniper have numerous negative impacts on the ecosystems upon which they encroach. Western juniper can cause increased erosion, decreased production of herbaceous vegetation, decreased streamflows and increased stream sedimentation, increased bare ground, and changes in wildlife diversity and species abundance. However, because western juniper is both expensive and difficult to kill or harvest, and because there is a limited market for its wood and other western juniper products, the expansion of western juniper populations throughout parts of the Pacific Northwest occurs largely unimpeded. Within western juniper's range in central and eastern Oregon, much of the land is owned by and operated as beef cattle ranches. As western juniper encroach upon a site, the reduction in herbaceous vegetation causes a decrease in the number of livestock the site can support. As the ability of rangeland to support livestock declines, ranch profits will also likely diminish Despite this trend, clearing of western juniper has historically been limited. This research presents discrete-time, dynamic economic models developed to depict various representative ranches located in the John Day Ecological Province of Oregon, the area of the greatest distribution of western jumper and where the majority of research regarding the western juniper has been conducted. The bioeconomic models are developed to examine optimal ranch management practices. The optimization criterion is to maximize the net present value of gross margins through decisions regarding herd size and composition, cattle sales, and the manipulation of forage production through juniper management practices. Comparisons are made to models in which juniper control is not a management option. Results indicate that it is indeed profitable for ranchers to practice juniper management on rangeland pastures. Models that included juniper management options consistently resulted in treatment of a minimum of seventy percent of juniper-encroached rangelands, larger equilibrium herd sizes, and greater gross margins. Erosion levels, and therefore potential stream sedimentation, was substantially lower in the models that contained juniper management options. Other environmental externalities included increased quail densities, but lower deer and elk populations. Close

• 47. [Article] Community structure of old-growth Juniperus occidentalis woodlands

  Knowledge of old-growth Juniperus occidentalis woodlands, which occur in central and eastern Oregon, is limited. Wise management of these woodlands necessitates a better understanding of the community ...

  Citation × Citation Citation Abstract Copy Title: Community structure of old-growth Juniperus occidentalis woodlands Author: Waichler, Wendy Sims Knowledge of old-growth Juniperus occidentalis woodlands, which occur in central and eastern Oregon, is limited. Wise management of these woodlands necessitates a better understanding of the community ecology. The community structure of woodlands at seven sites in three areas of central Oregon was studied. Measurements taken at nine plots per site included tree density, canopy cover, heights, diameters, and canopy areas; cover of each understory species and other ground covers; density of shrubs by species and condition; density of woody debris as downed pieces and standing dead trees; and topographic and soil parameters. Tree cores were taken for aging, although heartwood rot is pervasive in older trees. Factors of interest included cover and richness in all vegetative layers, variability within and between sites, and comparison of J. occidentalis woodlands to other old-growth communities. J. occidentalis woodlands were found to have a minimum of 80 trees over 200 years old per hectare, canopy cover of 10-35%, and understory cover of less than 20%. Woody detritus was primarily retained aloft and decomposed by weathering. Tree morphology was highly variable, but decadence was common. Outward physical attributes did not appear to be reliable predictors of tree age. Shrub cover was strongly correlated (r²=0.66) with the combination of elevation, ground cover by rock, and clay content of the soil. Perennial grass cover increased with elevation and the sand-sized soil fraction (r²=0.46). Understory cover, dominated by perennial grass, showed a weaker correlation with the same parameters (r²=0.20). Other significant findings included correlation of juniper cover with elevation, sand. and heat load (r²=0.38). Tree cover was found to increase by almost 1% for each 1% increase in sand content of the soil and by almost 8% for each 100m increase in elevation, while heat load, based on aspect. had a smaller effect. Plots grouped strongly by area. suggesting that there is a stronger influence of area than site on community composition for most of the sites and that differences between areas overwhelm the differences within areas. Title: Community structure of old-growth Juniperus occidentalis woodlands Author: Waichler, Wendy Sims Knowledge of old-growth Juniperus occidentalis woodlands, which occur in central and eastern Oregon, is limited. Wise management of these woodlands necessitates a better understanding of the community ecology. The community structure of woodlands at seven sites in three areas of central Oregon was studied. Measurements taken at nine plots per site included tree density, canopy cover, heights, diameters, and canopy areas; cover of each understory species and other ground covers; density of shrubs by species and condition; density of woody debris as downed pieces and standing dead trees; and topographic and soil parameters. Tree cores were taken for aging, although heartwood rot is pervasive in older trees. Factors of interest included cover and richness in all vegetative layers, variability within and between sites, and comparison of J. occidentalis woodlands to other old-growth communities. J. occidentalis woodlands were found to have a minimum of 80 trees over 200 years old per hectare, canopy cover of 10-35%, and understory cover of less than 20%. Woody detritus was primarily retained aloft and decomposed by weathering. Tree morphology was highly variable, but decadence was common. Outward physical attributes did not appear to be reliable predictors of tree age. Shrub cover was strongly correlated (r²=0.66) with the combination of elevation, ground cover by rock, and clay content of the soil. Perennial grass cover increased with elevation and the sand-sized soil fraction (r²=0.46). Understory cover, dominated by perennial grass, showed a weaker correlation with the same parameters (r²=0.20). Other significant findings included correlation of juniper cover with elevation, sand. and heat load (r²=0.38). Tree cover was found to increase by almost 1% for each 1% increase in sand content of the soil and by almost 8% for each 100m increase in elevation, while heat load, based on aspect. had a smaller effect. Plots grouped strongly by area. suggesting that there is a stronger influence of area than site on community composition for most of the sites and that differences between areas overwhelm the differences within areas. Close

• 48. [Article] Simulating Current Successional Trajectories in Sagebrush Ecosystems With Multiple Disturbances Using a State-and-Transition Modeling Framewor

  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 The Society ...

  Citation × Citation Citation Abstract Copy Title: Simulating Current Successional Trajectories in Sagebrush Ecosystems With Multiple Disturbances Using a State-and-Transition Modeling Framewor Author: Doescher, Paul S., Miller, Richard F., Neilson, Ronald P., Evers, Louisa B., Hemstrom, Miles 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 The Society for Range Management and can be found at: http://www.rangelands.org/. Title: Simulating Current Successional Trajectories in Sagebrush Ecosystems With Multiple Disturbances Using a State-and-Transition Modeling Framewor Author: Doescher, Paul S., Miller, Richard F., Neilson, Ronald P., Evers, Louisa B., Hemstrom, Miles 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 The Society for Range Management and can be found at: http://www.rangelands.org/. Close

• 49. [Article] "The Island" Research Natural Area : a vegetation study with time and location comparisons

  The purpose of this study was to document vegetation on "The Island", a Research Natural Area at the confluence of the Crooked River and the Deschutes River in central Oregon's Juniperus occidentalis Zone ...

  Citation × Citation Citation Abstract Copy Title: "The Island" Research Natural Area : a vegetation study with time and location comparisons Author: Fox, M. Anne, 1939- The purpose of this study was to document vegetation on "The Island", a Research Natural Area at the confluence of the Crooked River and the Deschutes River in central Oregon's Juniperus occidentalis Zone and to compare the results with an earlier study reported in 1964 from 1960-'61 data. Present-day comparisons were also made between "The Island" vegetation and three nearby sites. Percent cover and constancy of major tree, shrub, grass, and forb species were considered along with percent cover of litter, moss/lichen, rock and bare ground. Climatic data from the Metolius, OR Station were examined, and the literature of succession especially succession in the juniper and sagebrush steppe of the Great Basin was reviewed. Data from 1992-'93 show more woody vegetation on "The Island", both tree and shrub, than was measured thirty years ago. The only tree species present is Juniperus occidentalis, while major shrub species are Artemisia tridentata and Purshia tridentata. Grass cover appeared to be less, with a more even mix of the native perennial bunchgrass species Agropyron spicatum, Festuca idahoensis, Poa sandbergii, and Stipa thurberiana, than in the past when Agropyron spicatum and the alien annual grass, Bromus tectorum dominated. The two plant associations identified in the 1964 report by Driscoll, Juniperus occidentalis / Artemisia tridentata / Agropyron spicatum and Juniperus occidentalis / Purshia tridentata / Agropyron spicatum were still identifiable, but the shrub, Artemisia tridentata appeared to be entering areas where Purshia tridentata had dominated in the past study. The present-day comparison sites showed many similarities with sites on "The Island." The comparison sites in the Juniperus occidentalis / Artemisia tridentata / Agropyron spicatum association measured slightly more tree and shrub cover but similar grass cover when compared to "The Island." The comparison site in the Juniperus occidentalis / Purshia tridentata / Agropyron spicatum association had more tree cover and more Purshia tridentata cover, but less shrub cover generally and more grass cover than the same association on "The Island." Forbs represented less than one percent cover on all study sites. The differences recorded in 1992-'93 from that of the study thirty years ago may reflect successional processes at work and a lack of any major natural fires in the system. Title: "The Island" Research Natural Area : a vegetation study with time and location comparisons Author: Fox, M. Anne, 1939- The purpose of this study was to document vegetation on "The Island", a Research Natural Area at the confluence of the Crooked River and the Deschutes River in central Oregon's Juniperus occidentalis Zone and to compare the results with an earlier study reported in 1964 from 1960-'61 data. Present-day comparisons were also made between "The Island" vegetation and three nearby sites. Percent cover and constancy of major tree, shrub, grass, and forb species were considered along with percent cover of litter, moss/lichen, rock and bare ground. Climatic data from the Metolius, OR Station were examined, and the literature of succession especially succession in the juniper and sagebrush steppe of the Great Basin was reviewed. Data from 1992-'93 show more woody vegetation on "The Island", both tree and shrub, than was measured thirty years ago. The only tree species present is Juniperus occidentalis, while major shrub species are Artemisia tridentata and Purshia tridentata. Grass cover appeared to be less, with a more even mix of the native perennial bunchgrass species Agropyron spicatum, Festuca idahoensis, Poa sandbergii, and Stipa thurberiana, than in the past when Agropyron spicatum and the alien annual grass, Bromus tectorum dominated. The two plant associations identified in the 1964 report by Driscoll, Juniperus occidentalis / Artemisia tridentata / Agropyron spicatum and Juniperus occidentalis / Purshia tridentata / Agropyron spicatum were still identifiable, but the shrub, Artemisia tridentata appeared to be entering areas where Purshia tridentata had dominated in the past study. The present-day comparison sites showed many similarities with sites on "The Island." The comparison sites in the Juniperus occidentalis / Artemisia tridentata / Agropyron spicatum association measured slightly more tree and shrub cover but similar grass cover when compared to "The Island." The comparison site in the Juniperus occidentalis / Purshia tridentata / Agropyron spicatum association had more tree cover and more Purshia tridentata cover, but less shrub cover generally and more grass cover than the same association on "The Island." Forbs represented less than one percent cover on all study sites. The differences recorded in 1992-'93 from that of the study thirty years ago may reflect successional processes at work and a lack of any major natural fires in the system. Close

• 50. [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