Search

Search Results

• 1. [Article] Oak Habitat Metric: User's Guide

  The metric is encompassed in two documents, this Oak Habitat Metric User’s Guide and an Oak Habitat Calculator.

  Citation × Citation Citation Abstract Copy Title: Oak Habitat Metric: User's Guide Author: Defenders of Wildlife The metric is encompassed in two documents, this Oak Habitat Metric User’s Guide and an Oak Habitat Calculator. Title: Oak Habitat Metric: User's Guide Author: Defenders of Wildlife The metric is encompassed in two documents, this Oak Habitat Metric User’s Guide and an Oak Habitat Calculator. Close

• 2. [Article] Oak habitat user guide.pdf

  Citation × Citation Citation Abstract Copy Title: Oak habitat user guide.pdf Author: Defenders of Wildlife Title: Oak habitat user guide.pdf Author: Defenders of Wildlife Close

• 3. [Article] Oak_Habitat_Metric_Calculator.Version_1.0.protected-1.xlsx

  Citation × Citation Citation Abstract Copy Title: Oak_Habitat_Metric_Calculator.Version_1.0.protected-1.xlsx Author: Defenders of Wildlife Title: Oak_Habitat_Metric_Calculator.Version_1.0.protected-1.xlsx Author: Defenders of Wildlife Close

• 4. [Article] Food web studies in an oak woodland eco-system

  Citation × Citation Citation Abstract Copy Title: Food web studies in an oak woodland eco-system Author: Hamilton, Grace Anne Title: Food web studies in an oak woodland eco-system Author: Hamilton, Grace Anne Close

• 5. [Article] Mental and biophysical terrains of biodiversity : conservation of oak woodland on family forest

  This research analyzes how family forest owners conceptualize biodiversity in one high-conservation value area of oak woodland in the Willamette Valley of Western Oregon. Oregon white oak (Quercus garyanna) ...

  Citation × Citation Citation Abstract Copy Title: Mental and biophysical terrains of biodiversity : conservation of oak woodland on family forest Author: Fischer, Alexandra Paige This research analyzes how family forest owners conceptualize biodiversity in one high-conservation value area of oak woodland in the Willamette Valley of Western Oregon. Oregon white oak (Quercus garyanna) woodland, one of the most biologically diverse ecotypes in the state of Oregon, is in decline. Much of the oak ecotype occurs on the lands of family forest owners. Understanding owners' conceptions of biodiversity is important for the conservation of this important resource. Theories from sociology, social psychology, and policy analysis argue that information about people's knowledge and beliefs is important for understanding and influencing their behavior. This research explores the mental and biophysical terrains of owners' relationships with biodiversity. Through interdisciplinary methods - including concept mapping, in-depth interviews, property mapping and field reconnaissance - it explores the meanings that people give to biodiversity on their family properties. Findings indicate that 1) owners are knowledgeable about the key elements of biodiversity, and 2) their use of this knowledge in management reflects their beliefs about human relationships with nature and external market constraints. Title: Mental and biophysical terrains of biodiversity : conservation of oak woodland on family forest Author: Fischer, Alexandra Paige This research analyzes how family forest owners conceptualize biodiversity in one high-conservation value area of oak woodland in the Willamette Valley of Western Oregon. Oregon white oak (Quercus garyanna) woodland, one of the most biologically diverse ecotypes in the state of Oregon, is in decline. Much of the oak ecotype occurs on the lands of family forest owners. Understanding owners' conceptions of biodiversity is important for the conservation of this important resource. Theories from sociology, social psychology, and policy analysis argue that information about people's knowledge and beliefs is important for understanding and influencing their behavior. This research explores the mental and biophysical terrains of owners' relationships with biodiversity. Through interdisciplinary methods - including concept mapping, in-depth interviews, property mapping and field reconnaissance - it explores the meanings that people give to biodiversity on their family properties. Findings indicate that 1) owners are knowledgeable about the key elements of biodiversity, and 2) their use of this knowledge in management reflects their beliefs about human relationships with nature and external market constraints. Close

• 6. [Article] Oregon Conservation Strategy Habitats

  Abstract -- This dataset represents the extent and distribution of the habitats prioritized within the Oregon Conservation Strategy. Strategy Habitats are identified by ecoregion, and as such are only ...

  Citation × Citation Citation Abstract Copy Title: Oregon Conservation Strategy Habitats Abstract -- This dataset represents the extent and distribution of the habitats prioritized within the Oregon Conservation Strategy. Strategy Habitats are identified by ecoregion, and as such are only mapped within their associated Strategy Ecoregions (see http://oregonconservationstrategy.org/strategy-habitats/ for more information on all Strategy Habitats). The list of Strategy Habitats is: Aspen Woodlands, Coastal Dunes, Estuaries, Flowing Water and Riparian Habitats, Grasslands, Late Successional Mixed Conifer Forest, Natural Lakes, Oak Woodlands, Ponderosa Pine Woodlands, Sagebrush Habitats, and Wetlands. Title: Oregon Conservation Strategy Habitats Abstract -- This dataset represents the extent and distribution of the habitats prioritized within the Oregon Conservation Strategy. Strategy Habitats are identified by ecoregion, and as such are only mapped within their associated Strategy Ecoregions (see http://oregonconservationstrategy.org/strategy-habitats/ for more information on all Strategy Habitats). The list of Strategy Habitats is: Aspen Woodlands, Coastal Dunes, Estuaries, Flowing Water and Riparian Habitats, Grasslands, Late Successional Mixed Conifer Forest, Natural Lakes, Oak Woodlands, Ponderosa Pine Woodlands, Sagebrush Habitats, and Wetlands. Close

• 7. [Article] White-breasted nuthatch density and nesting ecology in oak woodlands of the Willamette Valley, Oregon

  Habitat loss causes a reduction in available resources for wildlife, alters the configuration of remaining habitat, and may isolate wildlife populations. White-breasted nuthatches (Sitta carolinensis) ...

  Citation × Citation Citation Abstract Copy Title: White-breasted nuthatch density and nesting ecology in oak woodlands of the Willamette Valley, Oregon Author: Viste-Sparkman, Karen Habitat loss causes a reduction in available resources for wildlife, alters the configuration of remaining habitat, and may isolate wildlife populations. White-breasted nuthatches (Sitta carolinensis) are experiencing long-term population declines in the Willamette Valley of Oregon, where they are historically associated with oak woodlands. As secondary cavity-nesters, white-breasted nuthatches may be limited by the availability of existing cavities for nesting and roosting. Oak vegetation in the Willamette Valley has changed since European-American settlement times from vast areas of open oak savanna to isolated closed-canopy stands separated by agricultural fields. We examined nuthatch density, nest cavity selection, and nest success in relation to oak woodland structure and landscape context. We conducted point transect surveys in 3 strata: woodland interiors, large woodland edges, and small woodlands. We located and monitored nuthatch nests and sampled vegetation at nest locations and matching random locations around each nest. Woodland structure and edge density were measured at a 178-m radius (home range) scale, and landscape context was measured using vegetation cover within a 1-km radius around point transects and nests. We used program DISTANCE to fit detection functions and calculate nuthatch densities. We used conditional logistic regression to compare nest locations with random locations, and analyzed nest success with Mayfield logistic regression. White-breasted nuthatch density was significantly higher in small woodlands than in edges of large woodlands, which had higher nuthatch density than woodland interiors. Density of nuthatches increased with a combination of oak cover within a 1-km radius of the point, edge density within a 178-m radius, and number of oak trees >50 cm diameter at breast height (dbh) within a 100-m radius. Nest cavities were situated in oak trees containing more cavities than random oak trees that had cavities, and oak trees used as nest trees had a larger dbh than oak trees within random plots. Local woodland structure at nest locations was characterized by larger trees, measured by greater mean dbh, canopy cover, and basal area of oaks than random locations within the home range. Nest success in natural cavities was 71% and was not predicted by attributes of nest cavities, nest trees, local woodland structure at nests, woodland structure at the home range scale, or landscape context. These results suggest that the most suitable habitat for white-breasted nuthatches in the Willamette Valley includes oak woodlands in close proximity to one another with a high proportion of edge and mature oak trees. Managers should preserve trees containing cavities and large oak trees whenever possible. Thinning of small oaks and removal of conifers in oak woodlands to create more open, savanna-like conditions may also promote the development of larger oaks with more spreading branches, providing more opportunities for cavities to form and more foraging surface area for nuthatches. Title: White-breasted nuthatch density and nesting ecology in oak woodlands of the Willamette Valley, Oregon Author: Viste-Sparkman, Karen Habitat loss causes a reduction in available resources for wildlife, alters the configuration of remaining habitat, and may isolate wildlife populations. White-breasted nuthatches (Sitta carolinensis) are experiencing long-term population declines in the Willamette Valley of Oregon, where they are historically associated with oak woodlands. As secondary cavity-nesters, white-breasted nuthatches may be limited by the availability of existing cavities for nesting and roosting. Oak vegetation in the Willamette Valley has changed since European-American settlement times from vast areas of open oak savanna to isolated closed-canopy stands separated by agricultural fields. We examined nuthatch density, nest cavity selection, and nest success in relation to oak woodland structure and landscape context. We conducted point transect surveys in 3 strata: woodland interiors, large woodland edges, and small woodlands. We located and monitored nuthatch nests and sampled vegetation at nest locations and matching random locations around each nest. Woodland structure and edge density were measured at a 178-m radius (home range) scale, and landscape context was measured using vegetation cover within a 1-km radius around point transects and nests. We used program DISTANCE to fit detection functions and calculate nuthatch densities. We used conditional logistic regression to compare nest locations with random locations, and analyzed nest success with Mayfield logistic regression. White-breasted nuthatch density was significantly higher in small woodlands than in edges of large woodlands, which had higher nuthatch density than woodland interiors. Density of nuthatches increased with a combination of oak cover within a 1-km radius of the point, edge density within a 178-m radius, and number of oak trees >50 cm diameter at breast height (dbh) within a 100-m radius. Nest cavities were situated in oak trees containing more cavities than random oak trees that had cavities, and oak trees used as nest trees had a larger dbh than oak trees within random plots. Local woodland structure at nest locations was characterized by larger trees, measured by greater mean dbh, canopy cover, and basal area of oaks than random locations within the home range. Nest success in natural cavities was 71% and was not predicted by attributes of nest cavities, nest trees, local woodland structure at nests, woodland structure at the home range scale, or landscape context. These results suggest that the most suitable habitat for white-breasted nuthatches in the Willamette Valley includes oak woodlands in close proximity to one another with a high proportion of edge and mature oak trees. Managers should preserve trees containing cavities and large oak trees whenever possible. Thinning of small oaks and removal of conifers in oak woodlands to create more open, savanna-like conditions may also promote the development of larger oaks with more spreading branches, providing more opportunities for cavities to form and more foraging surface area for nuthatches. Close

• 8. [Article] Butterfly and flower community composition among prairie-oak ecosystem habitats in the Willamette Valley, Oregon

  Prairie-oak ecosystems in the Willamette Valley, Oregon have experienced habitat loss and degradation; most of these ecosystems are fragmented into smaller patches. Prairie-oak butterfly species, in the ...

  Citation × Citation Citation Abstract Copy Title: Butterfly and flower community composition among prairie-oak ecosystem habitats in the Willamette Valley, Oregon Author: Powers, Breanna F. Prairie-oak ecosystems in the Willamette Valley, Oregon have experienced habitat loss and degradation; most of these ecosystems are fragmented into smaller patches. Prairie-oak butterfly species, in the Willamette Valley, have decreased dramatically due to loss or degradation of habitat. More research is needed on sustaining the populations of butterflies in prairie-oak ecosystems. The purpose of my study was to examine the role prairie-oak habitats have in structuring butterfly communities in the Willamette Valley. My objectives were to: (1) assess how butterfly community structure and species composition (density, abundance, and species richness) varies along an oak canopy cover gradient in order to understand the role of habitat type in structuring butterfly communities in prairie-oak ecosystems; (2) characterize community composition of nectar resources and environmental variables known to be important for butterfly species. I also investigated temporal and structural relationships between butterfly and flower communities. I found that butterfly abundance and density were greater (p < 0.02) in prairies than in oak savannas or oak woodlands; however, species richness did not differ among habitats (p = 0.54). Ordination of prairie-oak habitats in butterfly species space with a joint plot overlay of environmental variables revealed several strong correlations; butterfly community structure was negatively correlated with litter and oak canopy cover and positively correlated to vegetation cover. The prairie, oak savanna, and oak woodland habitat types differed in nectar species community structure, though this difference was small. Non-native species were some of the most abundant flowers species found in all stands. Butterfly communities were positively related to flower communities. I detected significant seasonal patterns among the habitat types in butterfly and flower communities. Prairies appear to be the most important habitat for native butterfly populations compared to oak savanna and oak woodlands. Flowers were most prevalent in prairies and prairies had the highest percentage of native flower species; the prevalence of non-native flower species was greatest in oak woodlands. My study may represent a short-term community transition as a result of management or it may represent a more permanent community. Further study is needed to understand the effects of different management strategies for habitat restoration and the presence of non-native flower species on butterflies in prairie-oak ecosystems in the Willamette Valley. Title: Butterfly and flower community composition among prairie-oak ecosystem habitats in the Willamette Valley, Oregon Author: Powers, Breanna F. Prairie-oak ecosystems in the Willamette Valley, Oregon have experienced habitat loss and degradation; most of these ecosystems are fragmented into smaller patches. Prairie-oak butterfly species, in the Willamette Valley, have decreased dramatically due to loss or degradation of habitat. More research is needed on sustaining the populations of butterflies in prairie-oak ecosystems. The purpose of my study was to examine the role prairie-oak habitats have in structuring butterfly communities in the Willamette Valley. My objectives were to: (1) assess how butterfly community structure and species composition (density, abundance, and species richness) varies along an oak canopy cover gradient in order to understand the role of habitat type in structuring butterfly communities in prairie-oak ecosystems; (2) characterize community composition of nectar resources and environmental variables known to be important for butterfly species. I also investigated temporal and structural relationships between butterfly and flower communities. I found that butterfly abundance and density were greater (p < 0.02) in prairies than in oak savannas or oak woodlands; however, species richness did not differ among habitats (p = 0.54). Ordination of prairie-oak habitats in butterfly species space with a joint plot overlay of environmental variables revealed several strong correlations; butterfly community structure was negatively correlated with litter and oak canopy cover and positively correlated to vegetation cover. The prairie, oak savanna, and oak woodland habitat types differed in nectar species community structure, though this difference was small. Non-native species were some of the most abundant flowers species found in all stands. Butterfly communities were positively related to flower communities. I detected significant seasonal patterns among the habitat types in butterfly and flower communities. Prairies appear to be the most important habitat for native butterfly populations compared to oak savanna and oak woodlands. Flowers were most prevalent in prairies and prairies had the highest percentage of native flower species; the prevalence of non-native flower species was greatest in oak woodlands. My study may represent a short-term community transition as a result of management or it may represent a more permanent community. Further study is needed to understand the effects of different management strategies for habitat restoration and the presence of non-native flower species on butterflies in prairie-oak ecosystems in the Willamette Valley. Close

• 9. [Article] Use of oak woodlands (Quercus garryana) for farm forestry and grazing in the Willamette Valley

  Citation × Citation Citation Abstract Copy Title: Use of oak woodlands (Quercus garryana) for farm forestry and grazing in the Willamette Valley Author: Hall, Frederick C. Title: Use of oak woodlands (Quercus garryana) for farm forestry and grazing in the Willamette Valley Author: Hall, Frederick C. Close

• 10. [Article] Restoring rare native habitats in the Willamette valley

  A landowner's guide for restoring oak woodlands, wetlands, prairies, and bottomland hardwood and riparian forests. HUC: 170900. Bounding coordinates: West Bounding Coordinate: -123.769586; East Bounding ...

  Citation × Citation Citation Abstract Copy Title: Restoring rare native habitats in the Willamette valley Author: Campbell, Bruce H. A landowner's guide for restoring oak woodlands, wetlands, prairies, and bottomland hardwood and riparian forests. HUC: 170900. Bounding coordinates: West Bounding Coordinate: -123.769586; East Bounding Coordinate: -121.631074; North Bounding Coordinate: 45.941295; South Bounding Coordinate: 43.350360. Title: Restoring rare native habitats in the Willamette valley Author: Campbell, Bruce H. A landowner's guide for restoring oak woodlands, wetlands, prairies, and bottomland hardwood and riparian forests. HUC: 170900. Bounding coordinates: West Bounding Coordinate: -123.769586; East Bounding Coordinate: -121.631074; North Bounding Coordinate: 45.941295; South Bounding Coordinate: 43.350360. Close

• 11. [Article] Stand structures of Oregon white oak (Quercus garryana) woodlands and their relationships to the environment in southwestern Oregon

  Large areas of non-coniferous communities in southwestern Oregon are thinned to reduce fire hazard and accomplish ecosystem restoration, under the assumption that current fuel loads are unnaturally high. ...

  Citation × Citation Citation Abstract Copy Title: Stand structures of Oregon white oak (Quercus garryana) woodlands and their relationships to the environment in southwestern Oregon Author: Gilligan, Laurie A. Large areas of non-coniferous communities in southwestern Oregon are thinned to reduce fire hazard and accomplish ecosystem restoration, under the assumption that current fuel loads are unnaturally high. Although Oregon white oak (Quercus garryana) woodlands are a characteristic landscape component in this region, little is known about their current or historical stand structures. Managers lack information on which to base restoration-focused fuel reduction prescriptions. I inventoried 40 Oregon white oak dominated woodlands across 2 study areas in southwestern Oregon, and describe here their stand characteristics and age structures. I assessed whether these varied systematically with site conditions or recorded fire history. Stands included various proportions of single- and multiple-stemmed trees and a range of tree densities and diameter- and age-class distributions. Variables that may indicate site moisture status were weakly associated with multivariate gradients in stand structure, and fire history also appeared related to several stand structures. Peak establishment of living Oregon white oaks generally occurred during 1850-1890, sometimes occurred in the early 1900’s, and recruitment rates were low post-fire suppression. Recruitment of sapling-sized oak trees (< 10 cm dbh, 1.3 m tall) was generally low and their ages ranged from 5 to 164 yr; they were not necessarily recent recruits. The range of stand and age structures, and the variation in their apparent relations to site factors and history, suggests that site-by-site management prescriptions may more effectively accomplish restoration goals than do current treatments. Prescriptions should include follow-up monitoring with attention to effects on oak recruitment. Title: Stand structures of Oregon white oak (Quercus garryana) woodlands and their relationships to the environment in southwestern Oregon Author: Gilligan, Laurie A. Large areas of non-coniferous communities in southwestern Oregon are thinned to reduce fire hazard and accomplish ecosystem restoration, under the assumption that current fuel loads are unnaturally high. Although Oregon white oak (Quercus garryana) woodlands are a characteristic landscape component in this region, little is known about their current or historical stand structures. Managers lack information on which to base restoration-focused fuel reduction prescriptions. I inventoried 40 Oregon white oak dominated woodlands across 2 study areas in southwestern Oregon, and describe here their stand characteristics and age structures. I assessed whether these varied systematically with site conditions or recorded fire history. Stands included various proportions of single- and multiple-stemmed trees and a range of tree densities and diameter- and age-class distributions. Variables that may indicate site moisture status were weakly associated with multivariate gradients in stand structure, and fire history also appeared related to several stand structures. Peak establishment of living Oregon white oaks generally occurred during 1850-1890, sometimes occurred in the early 1900’s, and recruitment rates were low post-fire suppression. Recruitment of sapling-sized oak trees (< 10 cm dbh, 1.3 m tall) was generally low and their ages ranged from 5 to 164 yr; they were not necessarily recent recruits. The range of stand and age structures, and the variation in their apparent relations to site factors and history, suggests that site-by-site management prescriptions may more effectively accomplish restoration goals than do current treatments. Prescriptions should include follow-up monitoring with attention to effects on oak recruitment. Close

• 12. [Article] Relative abundance and habitat associations of small mammals in two forest types in southern Oregon

  I studied small-mammal communities and their response to grazing in mixed-conifer forests and oak woodlands in the Cascade-Siskiyou National Monument in southern Oregon. My objectives were to (1) compare ...

  Citation × Citation Citation Abstract Copy Title: Relative abundance and habitat associations of small mammals in two forest types in southern Oregon Author: Johnston, Aaron N. I studied small-mammal communities and their response to grazing in mixed-conifer forests and oak woodlands in the Cascade-Siskiyou National Monument in southern Oregon. My objectives were to (1) compare small-mammal communities among forest types and grazing intensities, (2) identify riparian affiliated species, and (3) describe microhabitat associations. Over two years, I trapped 1,617 individual small mammals representing 20 species. Mixed-conifer forests had more species and greater abundances of small mammals than oak woodlands, but there were no significant differences between the forest types in species richness or diversity at the stand level, as most sites had 3 to 5 species at any given time. Evenness was higher in oak woodlands compared to mixed-conifer forests because of lower dominance by Peromyscus maniculatus and fewer rare species. P. maniculatus dominated both forest types. Neurotrichus gibbsii, Tamias amoenus, Tamias siskiyou, Neotoma cinerea, Clethrionomys californicus, Microtus californicus, Microtus longicaudus, and Microtus montanus were found only in mixed-conifer forests, whereas Peromyscus boylii were trapped exclusively in oak woodlands. Although the two forest types shared 10 species, Sorex trowbridgii and Peromyscus maniculatus were significantly (P < 0.05) more abundant in mixed-conifer forests, whereas Sorex vagrans, Reithrodontomys megalotis, Peromyscus truei, and Neotoma fuscipes were significantly more abundant in oak woodlands. Microtus townsendii was the only species that was equally abundant in both forest types, but was found exclusively within meadow sites in mixed-conifer forests. I found no significant differences in species richness, diversity, and evenness between heavy and lightly grazed sites. However, mean mammalian biomass was 138 g/ha lower in heavily grazed sites, and abundances were 89.3% of those in lightly grazed sites. Cumulative biomass and abundance across heavily grazed sites were 65% and 80%, respectively, of that in lightly grazed sites. Several relatively large species (e.g. Neotoma spp. and Microtus spp.) were less abundant or absent in heavily grazed sites. My results support previous studies that found lower abundances of small mammals associated with herbaceous cover (e.g. Microtus spp.) in heavily grazed sites and little or no effect for species associated with open habitats (e.g. Tamias spp.). I found significantly (P < 0.05) lower abundances of S. trowbridgii (conifer), Peromyscus spp. (oak), N. cinerea (conifer), N. fuscipes (oak), M. longicaudus (conifer), and M. californicus (conifer) in heavy versus lightly grazed sites. There were also fewer T. siskiyou, R. megalotis, and M. townsendii captured in heavy versus lightly grazed sites, but the differences were not significant (P > 0.05). S. vagrans and T. amoenus were significantly more abundant in heavily grazed sites. Sample sizes for the remaining species were too small for comparison (n < 6). N. gibbsii, C. californicus, and M. californicus were captured exclusively in lightly grazed sites; only T. amoenus was captured exclusively in a heavily grazed site. There was a significant (P < 0.05) decrease in the odds of catching R. megalotis, N. cinerea, N. fuscipes, and M. longicaudus on heavy versus lightly grazed sites after accounting for microhabitat associations and potential confounding factors. Odds of capture were significantly (P < 0.05) lower for P. maniculatus in heavy versus lightly grazed sites in oak woodlands, but there was less difference in abundance between grazing intensities in mixed-conifer forests. There was some evidence to suggest that grazing decreased the odds of capturing M. townsendii in riparian areas. Although I found significantly (P < 0.05) fewer S. trowbridgii in heavily grazed sites, my analysis indicated that microhabitat associations rather than grazing explained the difference. Grazing appeared to increase the use of riparian areas by Tamias spp. by removing herbaceous cover and increasing bare ground. I described microhabitat associations for 10 species and found a suite of species (S. trowbridgii, T. amoenus, T. siskiyou, N. cinerea) that were positively associated with coarse woody debris and/or snags. R. megalotis, M. longicaudus, and M. townsendii were affiliated with, but not obligated, to riparian areas. P. maniculatus were ubiquitous, but abundances were also higher in riparian areas compared with uplands. T. siskiyou and P. truei appeared to be associated with uplands rather than riparian areas. Although I captured few S. vagrans, N. gibbsii, M. californicus, and M. montanus, they were found in either riparian areas or around spring seeps, which support previous studies. My results supported the importance of riparian areas to small mammals as suggested by previous studies. Title: Relative abundance and habitat associations of small mammals in two forest types in southern Oregon Author: Johnston, Aaron N. I studied small-mammal communities and their response to grazing in mixed-conifer forests and oak woodlands in the Cascade-Siskiyou National Monument in southern Oregon. My objectives were to (1) compare small-mammal communities among forest types and grazing intensities, (2) identify riparian affiliated species, and (3) describe microhabitat associations. Over two years, I trapped 1,617 individual small mammals representing 20 species. Mixed-conifer forests had more species and greater abundances of small mammals than oak woodlands, but there were no significant differences between the forest types in species richness or diversity at the stand level, as most sites had 3 to 5 species at any given time. Evenness was higher in oak woodlands compared to mixed-conifer forests because of lower dominance by Peromyscus maniculatus and fewer rare species. P. maniculatus dominated both forest types. Neurotrichus gibbsii, Tamias amoenus, Tamias siskiyou, Neotoma cinerea, Clethrionomys californicus, Microtus californicus, Microtus longicaudus, and Microtus montanus were found only in mixed-conifer forests, whereas Peromyscus boylii were trapped exclusively in oak woodlands. Although the two forest types shared 10 species, Sorex trowbridgii and Peromyscus maniculatus were significantly (P < 0.05) more abundant in mixed-conifer forests, whereas Sorex vagrans, Reithrodontomys megalotis, Peromyscus truei, and Neotoma fuscipes were significantly more abundant in oak woodlands. Microtus townsendii was the only species that was equally abundant in both forest types, but was found exclusively within meadow sites in mixed-conifer forests. I found no significant differences in species richness, diversity, and evenness between heavy and lightly grazed sites. However, mean mammalian biomass was 138 g/ha lower in heavily grazed sites, and abundances were 89.3% of those in lightly grazed sites. Cumulative biomass and abundance across heavily grazed sites were 65% and 80%, respectively, of that in lightly grazed sites. Several relatively large species (e.g. Neotoma spp. and Microtus spp.) were less abundant or absent in heavily grazed sites. My results support previous studies that found lower abundances of small mammals associated with herbaceous cover (e.g. Microtus spp.) in heavily grazed sites and little or no effect for species associated with open habitats (e.g. Tamias spp.). I found significantly (P < 0.05) lower abundances of S. trowbridgii (conifer), Peromyscus spp. (oak), N. cinerea (conifer), N. fuscipes (oak), M. longicaudus (conifer), and M. californicus (conifer) in heavy versus lightly grazed sites. There were also fewer T. siskiyou, R. megalotis, and M. townsendii captured in heavy versus lightly grazed sites, but the differences were not significant (P > 0.05). S. vagrans and T. amoenus were significantly more abundant in heavily grazed sites. Sample sizes for the remaining species were too small for comparison (n < 6). N. gibbsii, C. californicus, and M. californicus were captured exclusively in lightly grazed sites; only T. amoenus was captured exclusively in a heavily grazed site. There was a significant (P < 0.05) decrease in the odds of catching R. megalotis, N. cinerea, N. fuscipes, and M. longicaudus on heavy versus lightly grazed sites after accounting for microhabitat associations and potential confounding factors. Odds of capture were significantly (P < 0.05) lower for P. maniculatus in heavy versus lightly grazed sites in oak woodlands, but there was less difference in abundance between grazing intensities in mixed-conifer forests. There was some evidence to suggest that grazing decreased the odds of capturing M. townsendii in riparian areas. Although I found significantly (P < 0.05) fewer S. trowbridgii in heavily grazed sites, my analysis indicated that microhabitat associations rather than grazing explained the difference. Grazing appeared to increase the use of riparian areas by Tamias spp. by removing herbaceous cover and increasing bare ground. I described microhabitat associations for 10 species and found a suite of species (S. trowbridgii, T. amoenus, T. siskiyou, N. cinerea) that were positively associated with coarse woody debris and/or snags. R. megalotis, M. longicaudus, and M. townsendii were affiliated with, but not obligated, to riparian areas. P. maniculatus were ubiquitous, but abundances were also higher in riparian areas compared with uplands. T. siskiyou and P. truei appeared to be associated with uplands rather than riparian areas. Although I captured few S. vagrans, N. gibbsii, M. californicus, and M. montanus, they were found in either riparian areas or around spring seeps, which support previous studies. My results supported the importance of riparian areas to small mammals as suggested by previous studies. Close

• 13. [Article] Some factors controlling the establishment and distribution of Quercus agrifolia Nee and Q. engelmannii Greene in certain southern California oak woodlands

  The structure of two oak woodland types in the Santa Rosa region of the Santa Ana Mountains of southern California has been described by Zuill (1967). One type called the grass oak woodland (GOW) is composed ...

  Citation × Citation Citation Abstract Copy Title: Some factors controlling the establishment and distribution of Quercus agrifolia Nee and Q. engelmannii Greene in certain southern California oak woodlands Author: Snow, Gerald Eldon The structure of two oak woodland types in the Santa Rosa region of the Santa Ana Mountains of southern California has been described by Zuill (1967). One type called the grass oak woodland (GOW) is composed mainly of Q. engelmannii on hills and slopes. The other type called the dense oak woodland (DOW) is composed equally of Q. engelmannii and Q. agrifolia with twice the density of the GOW and is located in valleys with granite rock outcrops. An apparent lack of seedlings and saplings was noted in the area. The present study focuses on an explanation for the distribution patterns of the two oak species in the field and the factors which might be most important in influencing seedling establishment. Quercus agrifolia is restricted to cool moist protected locations on the north side and in fractures of rock outcrops because its acorns are sensitive to moisture loss on air drying, require constantly moist conditions for one to five weeks for water uptake to effect germination and have very rapid shoot development after germination. Seedlings may be intolerant of high temperatures in open grass litter, and seedlings and saplings appear less tolerant of fire than Q. engelmannii, which would also tend to restrict Q. agrifolia to protected locations around rock outcrops. The distribution of Q. engelmannii trees with respect to rock outcrops does not differ from a random distribution and the few that are associated with outcrops show a random distribution with respect to position around outcrops. The occurrence of Q. engelmannii in more open exposed habitats may be due to its acorns' tolerance to moisture loss on air drying, their ability to germinate with little or n6 additional water uptake, its self-planting mechanism and delayed shoot development, and the drought deciduous habit of seedlings and their tolerance to fire. In the laboratory the drought capable of killing 50% of the seedlings is about 100 bars soil moisture tension for Q. engelmannii and about 250 bars for Q. agrifolia. The survival of Q. agrifolia under a greater degree of soil drought is mainly attributable to its higher root: shoot ratio under these particular conditions. Seedlings of both species would be expected to survive any drought recorded in the field between 1968 and 1970 at their expected rooting depth. After a very wet rainy season none of the mature trees experienced any moisture stress by the end of the dry season even though the near surface soils were quite dry. After a quite dry year trees in the DOW showed significantly greater moisture stress than those on a hilltop in the GOW. The moisture stress measurements of trees and soil moisture determinations down to 86 cm indicate that all the mature trees are rooted mainly below 86 cm. At least one large tree is apparently rooted down to 6 m. A planting of Q. agrifolia acorns that were buried to simulate squirrel caches survived to establish many more seedlings than surface planted acorns due mainly to protection from predation and drying and to conditions affording good radicle penetration. In an open planting cattle destroyed all the seedlings that were established while most of the seedlings remained in a planting closed to cattle. The complete lack of oak reproduction in open habitats and the restriction of reproduction for both species to rock outcrops since 1910 is attributable to cattle grazing, which has been continuous since about 1910. The last reproduction of Q. engelmannii in the GOW's without outcrops and the peak reproduction of Q. agrifolia in the DOW occurred between 1890 and 1910. This may be explained partly by the fact that for at least 10 years during this time livestock were excluded due to a dry land farming operation in the area. More than half of the living Q. engelmannii were established before any known influence of European men and their livestock (1820) and there has been a general decline in establishment since then. This might be expected since they usually occur in open and exposed habitats which would be most subject to grazing pressure. There was a simultaneous establishment and rapid buildup of the Q. agrifolia population around rock outcrops in the DOW with the entrance of European man and his livestock which may be due to ground squirrels depositing acorns around their burrows which are often associated with rock outcrops. These squirrels are known to come into new areas after disturbance by man. Also about this time filaree, a new preferred food source for squirrels (in addition to acorns), was being established on California range lands which probably resulted in an increase in the squirrel population. An effective squirrel poisoning program was begun in the 1920's and this may also account for the decreased establishment of Q. agrifolia since this time even around rock outcrops. Title: Some factors controlling the establishment and distribution of Quercus agrifolia Nee and Q. engelmannii Greene in certain southern California oak woodlands Author: Snow, Gerald Eldon The structure of two oak woodland types in the Santa Rosa region of the Santa Ana Mountains of southern California has been described by Zuill (1967). One type called the grass oak woodland (GOW) is composed mainly of Q. engelmannii on hills and slopes. The other type called the dense oak woodland (DOW) is composed equally of Q. engelmannii and Q. agrifolia with twice the density of the GOW and is located in valleys with granite rock outcrops. An apparent lack of seedlings and saplings was noted in the area. The present study focuses on an explanation for the distribution patterns of the two oak species in the field and the factors which might be most important in influencing seedling establishment. Quercus agrifolia is restricted to cool moist protected locations on the north side and in fractures of rock outcrops because its acorns are sensitive to moisture loss on air drying, require constantly moist conditions for one to five weeks for water uptake to effect germination and have very rapid shoot development after germination. Seedlings may be intolerant of high temperatures in open grass litter, and seedlings and saplings appear less tolerant of fire than Q. engelmannii, which would also tend to restrict Q. agrifolia to protected locations around rock outcrops. The distribution of Q. engelmannii trees with respect to rock outcrops does not differ from a random distribution and the few that are associated with outcrops show a random distribution with respect to position around outcrops. The occurrence of Q. engelmannii in more open exposed habitats may be due to its acorns' tolerance to moisture loss on air drying, their ability to germinate with little or n6 additional water uptake, its self-planting mechanism and delayed shoot development, and the drought deciduous habit of seedlings and their tolerance to fire. In the laboratory the drought capable of killing 50% of the seedlings is about 100 bars soil moisture tension for Q. engelmannii and about 250 bars for Q. agrifolia. The survival of Q. agrifolia under a greater degree of soil drought is mainly attributable to its higher root: shoot ratio under these particular conditions. Seedlings of both species would be expected to survive any drought recorded in the field between 1968 and 1970 at their expected rooting depth. After a very wet rainy season none of the mature trees experienced any moisture stress by the end of the dry season even though the near surface soils were quite dry. After a quite dry year trees in the DOW showed significantly greater moisture stress than those on a hilltop in the GOW. The moisture stress measurements of trees and soil moisture determinations down to 86 cm indicate that all the mature trees are rooted mainly below 86 cm. At least one large tree is apparently rooted down to 6 m. A planting of Q. agrifolia acorns that were buried to simulate squirrel caches survived to establish many more seedlings than surface planted acorns due mainly to protection from predation and drying and to conditions affording good radicle penetration. In an open planting cattle destroyed all the seedlings that were established while most of the seedlings remained in a planting closed to cattle. The complete lack of oak reproduction in open habitats and the restriction of reproduction for both species to rock outcrops since 1910 is attributable to cattle grazing, which has been continuous since about 1910. The last reproduction of Q. engelmannii in the GOW's without outcrops and the peak reproduction of Q. agrifolia in the DOW occurred between 1890 and 1910. This may be explained partly by the fact that for at least 10 years during this time livestock were excluded due to a dry land farming operation in the area. More than half of the living Q. engelmannii were established before any known influence of European men and their livestock (1820) and there has been a general decline in establishment since then. This might be expected since they usually occur in open and exposed habitats which would be most subject to grazing pressure. There was a simultaneous establishment and rapid buildup of the Q. agrifolia population around rock outcrops in the DOW with the entrance of European man and his livestock which may be due to ground squirrels depositing acorns around their burrows which are often associated with rock outcrops. These squirrels are known to come into new areas after disturbance by man. Also about this time filaree, a new preferred food source for squirrels (in addition to acorns), was being established on California range lands which probably resulted in an increase in the squirrel population. An effective squirrel poisoning program was begun in the 1920's and this may also account for the decreased establishment of Q. agrifolia since this time even around rock outcrops. Close

• 14. [Article] Stand Structures of Oregon White Oak Woodlands, Regeneration, and Their Relationships to the Environment in Southwestern Oregon

  This is the publisher’s final pdf. The published article is copyrighted by Northwest Scientific Association and can be found at: http://www.northwestscience.org/.

  Citation × Citation Citation Abstract Copy Title: Stand Structures of Oregon White Oak Woodlands, Regeneration, and Their Relationships to the Environment in Southwestern Oregon Author: Gilligan, Laurie A., Muir, Patricia S. This is the publisher’s final pdf. The published article is copyrighted by Northwest Scientific Association and can be found at: http://www.northwestscience.org/. Title: Stand Structures of Oregon White Oak Woodlands, Regeneration, and Their Relationships to the Environment in Southwestern Oregon Author: Gilligan, Laurie A., Muir, Patricia S. This is the publisher’s final pdf. The published article is copyrighted by Northwest Scientific Association and can be found at: http://www.northwestscience.org/. Close

• 15. [Article] Bird Abundance and Microhabitat Associations with Oak Mistletoe in Willamette Valley Oak Woodlands

  In the last 200 years there have been significant declines in the amount and structural complexity of oak-dominated forests and savannahs in the Pacific Northwest. Restoring oak systems often involves ...

  Citation × Citation Citation Abstract Copy Title: Bird Abundance and Microhabitat Associations with Oak Mistletoe in Willamette Valley Oak Woodlands Author: Pritchard, Kyle R. In the last 200 years there have been significant declines in the amount and structural complexity of oak-dominated forests and savannahs in the Pacific Northwest. Restoring oak systems often involves selectively thinning stands of oaks in order to reduce competition for sunlight. In choosing which trees to cut, land managers often remove trees with obvious signs of disease or infection. One such infection is the parasitic mistletoe Phoradendron villosum, commonly referred to as Oak Mistletoe. However, the consequences of removing mistletoe-laden trees from the woodlands for oak-associated wildlife have not been studied. Mistletoe species play an important role in ecosystems globally, by providing habitat resources for wildlife, but the role of Oak Mistletoe in an oak-dominated ecosystem is almost completely undocumented. In order to investigate relationships between Oak Mistletoe and bird abundance and diversity, I quantified breeding bird use of Oregon White Oaks (Quercus garryana) with mistletoe loads between zero and 112 plants per tree, at five study sites in the Willamette Valley in the spring of 2014. In addition, I quantified six microhabitat features related to mistletoe infection, including branch swellings, dead wood, loose/missing bark, natural cavities, excavated cavities, deep cracks in the bole, and bole coverage by Poison Oak (Toxicodendron diversilobum). My results suggest that 1) structural heterogeneity within the crown of the tree and 2) bird abundance, species richness, and use of trees are positively associated with mistletoe load. In order to investigate the use of Oak Mistletoe fruits as a wildlife food resource, I recruited citizen scientists to record observations of birds feeding on mistletoe fruits in the fall of 2014 and winter of 2015 in western Oregon. In addition, I installed six camera traps in Oregon White Oak trees in order to capture additional observations of birds and other wildlife feeding on Oak Mistletoe fruits. My results suggest that Oak Mistletoe is a fall and winter food resource for Western Bluebirds (Sialia mexicana), American Robins (Turdus migratorius), Cedar Waxwings (Bombycilla cedrorum), Wild Turkeys (Meleagris gallopavo), and Western Grey Squirrels (Sciurus griseus). In this study, Western Bluebirds were observed to feed on mistletoe fruits up to 14 times more frequently than other bird species. By retaining some trees with mistletoe in the crown, land managers may be able to maintain the habitat quality for some wildlife species that use the microhabitat features and fruit resources associated with mistletoe. Title: Bird Abundance and Microhabitat Associations with Oak Mistletoe in Willamette Valley Oak Woodlands Author: Pritchard, Kyle R. In the last 200 years there have been significant declines in the amount and structural complexity of oak-dominated forests and savannahs in the Pacific Northwest. Restoring oak systems often involves selectively thinning stands of oaks in order to reduce competition for sunlight. In choosing which trees to cut, land managers often remove trees with obvious signs of disease or infection. One such infection is the parasitic mistletoe Phoradendron villosum, commonly referred to as Oak Mistletoe. However, the consequences of removing mistletoe-laden trees from the woodlands for oak-associated wildlife have not been studied. Mistletoe species play an important role in ecosystems globally, by providing habitat resources for wildlife, but the role of Oak Mistletoe in an oak-dominated ecosystem is almost completely undocumented. In order to investigate relationships between Oak Mistletoe and bird abundance and diversity, I quantified breeding bird use of Oregon White Oaks (Quercus garryana) with mistletoe loads between zero and 112 plants per tree, at five study sites in the Willamette Valley in the spring of 2014. In addition, I quantified six microhabitat features related to mistletoe infection, including branch swellings, dead wood, loose/missing bark, natural cavities, excavated cavities, deep cracks in the bole, and bole coverage by Poison Oak (Toxicodendron diversilobum). My results suggest that 1) structural heterogeneity within the crown of the tree and 2) bird abundance, species richness, and use of trees are positively associated with mistletoe load. In order to investigate the use of Oak Mistletoe fruits as a wildlife food resource, I recruited citizen scientists to record observations of birds feeding on mistletoe fruits in the fall of 2014 and winter of 2015 in western Oregon. In addition, I installed six camera traps in Oregon White Oak trees in order to capture additional observations of birds and other wildlife feeding on Oak Mistletoe fruits. My results suggest that Oak Mistletoe is a fall and winter food resource for Western Bluebirds (Sialia mexicana), American Robins (Turdus migratorius), Cedar Waxwings (Bombycilla cedrorum), Wild Turkeys (Meleagris gallopavo), and Western Grey Squirrels (Sciurus griseus). In this study, Western Bluebirds were observed to feed on mistletoe fruits up to 14 times more frequently than other bird species. By retaining some trees with mistletoe in the crown, land managers may be able to maintain the habitat quality for some wildlife species that use the microhabitat features and fruit resources associated with mistletoe. Close

• 16. [Article] Monitoring the effects of oak woodland restoration on birds in the Willamette Valley, Oregon

  Pathways Internship Program

  Citation × Citation Citation Abstract Copy Title: Monitoring the effects of oak woodland restoration on birds in the Willamette Valley, Oregon Author: Martinez, Elena Pathways Internship Program Title: Monitoring the effects of oak woodland restoration on birds in the Willamette Valley, Oregon Author: Martinez, Elena Pathways Internship Program Close

• 17. [Article] Klamath River Canyon oak thin and Big Bend fuels reduction environmental assessment

  24 pp. Tables, appendices, maps, references, illus. T 40S 6E Sec 11, 12, 13, 14, 23, 26, 27, 34; T 41S 6E Sec 03, 04, 09. Captured August 8, 2007.

  Citation × Citation Citation Abstract Copy Title: Klamath River Canyon oak thin and Big Bend fuels reduction environmental assessment Author: United States. Bureau of Land Management. Lakeview District Year: 2008, 2006 24 pp. Tables, appendices, maps, references, illus. T 40S 6E Sec 11, 12, 13, 14, 23, 26, 27, 34; T 41S 6E Sec 03, 04, 09. Captured August 8, 2007. Title: Klamath River Canyon oak thin and Big Bend fuels reduction environmental assessment Author: United States. Bureau of Land Management. Lakeview District Year: 2008, 2006 24 pp. Tables, appendices, maps, references, illus. T 40S 6E Sec 11, 12, 13, 14, 23, 26, 27, 34; T 41S 6E Sec 03, 04, 09. Captured August 8, 2007. Close

• 18. [Article] Klamath River Canyon oak thin and Big Bend fuels reduction decision record and finding of no significant impact

  6 pp. T 40S 6E Sec 11, 12, 13, 14, 23, 26, 27, 34; T 41S 6E Sec 03, 04, 09. Captured August 8, 2007.

  Citation × Citation Citation Abstract Copy Title: Klamath River Canyon oak thin and Big Bend fuels reduction decision record and finding of no significant impact Author: United States. Bureau of Land Management. Lakeview District Year: 2008, 2006 6 pp. T 40S 6E Sec 11, 12, 13, 14, 23, 26, 27, 34; T 41S 6E Sec 03, 04, 09. Captured August 8, 2007. Title: Klamath River Canyon oak thin and Big Bend fuels reduction decision record and finding of no significant impact Author: United States. Bureau of Land Management. Lakeview District Year: 2008, 2006 6 pp. T 40S 6E Sec 11, 12, 13, 14, 23, 26, 27, 34; T 41S 6E Sec 03, 04, 09. Captured August 8, 2007. Close

• 19. [Article] Vegetation and climate of the northwest coast of North America during the last 500 K.Y. : high–resolution pollen evidence from the northern California margin

  Pollen analyses of sediments from Holes 1019C, 1019E, 1020C, and 1020D as well as piston Core EW9504-17 provide continuous, chronostratigraphically controlled proxy vegetation and climate data for coastal ...

  Citation × Citation Citation Abstract Copy Title: Vegetation and climate of the northwest coast of North America during the last 500 K.Y. : high–resolution pollen evidence from the northern California margin Author: Lyle, Mitchell, Heusser, Linda, Mix, Alan C. Pollen analyses of sediments from Holes 1019C, 1019E, 1020C, and 1020D as well as piston Core EW9504-17 provide continuous, chronostratigraphically controlled proxy vegetation and climate data for coastal northwest North America for the last ~500 k.y. Systematic changes in the representation of the diagnostic components of northern California plant assemblages clearly show orbital-scale variations. Interglacials are all marked by an abrupt increase in alder followed by expansion of lowland oak woodland and redwood forests. Glacials are dominated by montane forest and woodland assemblages. This sequence reflects large-scale climatic controls (e.g., orbital-scale variation in insolation and Northern Hemisphere ice sheets) in western North America over the last five glacial cycles. Regional climatic control (variations in sea-surface conditions) is implied by the differential development of xeric oak and mesic redwood communities. Title: Vegetation and climate of the northwest coast of North America during the last 500 K.Y. : high–resolution pollen evidence from the northern California margin Author: Lyle, Mitchell, Heusser, Linda, Mix, Alan C. Pollen analyses of sediments from Holes 1019C, 1019E, 1020C, and 1020D as well as piston Core EW9504-17 provide continuous, chronostratigraphically controlled proxy vegetation and climate data for coastal northwest North America for the last ~500 k.y. Systematic changes in the representation of the diagnostic components of northern California plant assemblages clearly show orbital-scale variations. Interglacials are all marked by an abrupt increase in alder followed by expansion of lowland oak woodland and redwood forests. Glacials are dominated by montane forest and woodland assemblages. This sequence reflects large-scale climatic controls (e.g., orbital-scale variation in insolation and Northern Hemisphere ice sheets) in western North America over the last five glacial cycles. Regional climatic control (variations in sea-surface conditions) is implied by the differential development of xeric oak and mesic redwood communities. Close

• 20. [Article] Granary-Site Selection by Acorn Woodpeckers in the Willamette Valley,

  © 2006 by the Northwest Scientific Association

  Citation × Citation Citation Abstract Copy Title: Granary-Site Selection by Acorn Woodpeckers in the Willamette Valley, Author: Rosenberg, Daniel K., Johnson, Eric M. © 2006 by the Northwest Scientific Association Title: Granary-Site Selection by Acorn Woodpeckers in the Willamette Valley, Author: Rosenberg, Daniel K., Johnson, Eric M. © 2006 by the Northwest Scientific Association Close