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• 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