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• 31. [Article] A Four Year Study of the Effects of Substrate Depth on the Survival of Different Plant Species in Portland, OR

  The changes in green roof plant species composition was observed after a four year time period. Twelve plots were planted in either native or non-native species at two different substrate depths according ...

  Citation × Citation Citation Abstract Copy Title: A Four Year Study of the Effects of Substrate Depth on the Survival of Different Plant Species in Portland, OR Author: Viray, Arjun Year: 2017 The changes in green roof plant species composition was observed after a four year time period. Twelve plots were planted in either native or non-native species at two different substrate depths according to a 2 by 2 factorial design. The list of original species from installation was used to identify which species survived over time in their respective plots. After four years, 9 out of 12 native species and 13 out of 14 species survived. The high survival of 26 original species must be compared to the colonization of 68 new species. With minimal maintenance, new species colonized plots. Extensive plots were composed of 33% original planting and 67% colonizing species. Intensive plots were composed of 24% original plantings and 76% new species. The original species that had the highest survival were Sedums and Festuca. Authors: Arjun Vijay, Olyssa Starry Presenter: Arjun Viray Title: A Four Year Study of the Effects of Substrate Depth on the Survival of Different Plant Species in Portland, OR Author: Viray, Arjun Year: 2017 The changes in green roof plant species composition was observed after a four year time period. Twelve plots were planted in either native or non-native species at two different substrate depths according to a 2 by 2 factorial design. The list of original species from installation was used to identify which species survived over time in their respective plots. After four years, 9 out of 12 native species and 13 out of 14 species survived. The high survival of 26 original species must be compared to the colonization of 68 new species. With minimal maintenance, new species colonized plots. Extensive plots were composed of 33% original planting and 67% colonizing species. Intensive plots were composed of 24% original plantings and 76% new species. The original species that had the highest survival were Sedums and Festuca. Authors: Arjun Vijay, Olyssa Starry Presenter: Arjun Viray Close

• 32. [Article] 2006 OPRD- Oregon Chub Population Monitoring on Oregon State Park Lands Progress Reports 2006

  Abstract -- Oregon chub Oregonichthys crameri, small minnows endemic to the Willamette River drainage of western Oregon (Markle et al. 1991), were federally listed as endangered under the Endangered Species ...

  Citation × Citation Citation Abstract Copy Title: 2006 OPRD- Oregon Chub Population Monitoring on Oregon State Park Lands Progress Reports 2006 Abstract -- Oregon chub Oregonichthys crameri, small minnows endemic to the Willamette River drainage of western Oregon (Markle et al. 1991), were federally listed as endangered under the Endangered Species Act in 1993 (Markle and Pearsons 1990; Rhew 1993). This species was formerly distributed throughout the Willamette River Valley (Snyder 1908) in off-channel habitats such as beaver ponds, oxbows, backwater sloughs, and flooded marshes. These habitats usually have little or no water flow, have silty and organic substrate, and have an abundance of aquatic vegetation and cover for hiding and spawning. In the last 100 years, off-channel habitats have disappeared because of changes in seasonal flows and habitat characteristics resulting from the construction of flood control dams, revetments, channelization, diking, and the drainage of wetlands for bottomland agriculture. This loss of habitat combined with the introduction of non-native species to the Willamette Valley resulted in a restricted distribution and sharp decline in Oregon chub abundance. The Oregon chub is further threatened by predation and competition by non-native species such as largemouth bass Micropterus salmoides, crappies Pomoxis sp., sunfishes Lepomis sp., bullheads Ameiurus sp., and western mosquitofish Gambusia affinis. To evaluate abundance and distribution of Oregon chub populations, the Oregon Department of Fish and Wildlife has conducted surveys since 1991. Information collected also included the presence of non-native and native species, the characteristics of Oregon chub habitats, the characteristics of potential introduction sites, evaluation of Oregon chub introductions, and life history characteristics (Scheerer 2002, Scheerer and McDonald 2003, Scheerer et al. 2006). The Oregon Chub Recovery Plan (U.S. Fish and Wildlife Service 1998) set recovery criteria for downlisting the species to “threatened” and for delisting the species. The criteria for downlisting the species are: 1) establish and manage 10 populations of at least 500 adult fish, 2) all of these populations must exhibit a stable or increasing trend for five years, and 3) at least three populations meeting criterion 1 and 2 must be located in each of the three recovery areas (Middle Fork Willamette River, Santiam River, and Mid-Willamette River tributaries). In 2006, there were 18 populations totaling 500 or more individuals. Thirteen of these populations met the above criteria. Eight were located in the Middle Fork Willamette drainage, three were located in the Mid-Willamette drainage, and two were located in the Santiam drainage (Scheerer et al. 2006). The status of this species has improved substantially over the past decade and with the addition of a single Santiam population, the downlisting criteria will be met (Scheerer et al. 2006). Title: 2006 OPRD- Oregon Chub Population Monitoring on Oregon State Park Lands Progress Reports 2006 Abstract -- Oregon chub Oregonichthys crameri, small minnows endemic to the Willamette River drainage of western Oregon (Markle et al. 1991), were federally listed as endangered under the Endangered Species Act in 1993 (Markle and Pearsons 1990; Rhew 1993). This species was formerly distributed throughout the Willamette River Valley (Snyder 1908) in off-channel habitats such as beaver ponds, oxbows, backwater sloughs, and flooded marshes. These habitats usually have little or no water flow, have silty and organic substrate, and have an abundance of aquatic vegetation and cover for hiding and spawning. In the last 100 years, off-channel habitats have disappeared because of changes in seasonal flows and habitat characteristics resulting from the construction of flood control dams, revetments, channelization, diking, and the drainage of wetlands for bottomland agriculture. This loss of habitat combined with the introduction of non-native species to the Willamette Valley resulted in a restricted distribution and sharp decline in Oregon chub abundance. The Oregon chub is further threatened by predation and competition by non-native species such as largemouth bass Micropterus salmoides, crappies Pomoxis sp., sunfishes Lepomis sp., bullheads Ameiurus sp., and western mosquitofish Gambusia affinis. To evaluate abundance and distribution of Oregon chub populations, the Oregon Department of Fish and Wildlife has conducted surveys since 1991. Information collected also included the presence of non-native and native species, the characteristics of Oregon chub habitats, the characteristics of potential introduction sites, evaluation of Oregon chub introductions, and life history characteristics (Scheerer 2002, Scheerer and McDonald 2003, Scheerer et al. 2006). The Oregon Chub Recovery Plan (U.S. Fish and Wildlife Service 1998) set recovery criteria for downlisting the species to “threatened” and for delisting the species. The criteria for downlisting the species are: 1) establish and manage 10 populations of at least 500 adult fish, 2) all of these populations must exhibit a stable or increasing trend for five years, and 3) at least three populations meeting criterion 1 and 2 must be located in each of the three recovery areas (Middle Fork Willamette River, Santiam River, and Mid-Willamette River tributaries). In 2006, there were 18 populations totaling 500 or more individuals. Thirteen of these populations met the above criteria. Eight were located in the Middle Fork Willamette drainage, three were located in the Mid-Willamette drainage, and two were located in the Santiam drainage (Scheerer et al. 2006). The status of this species has improved substantially over the past decade and with the addition of a single Santiam population, the downlisting criteria will be met (Scheerer et al. 2006). Close

• 33. [Article] Non-­Native Invasive Aquatic Plant and Mussel Survey of Six Umpqua National Forest Area Lakes

  Six lakes and ponds located within or near the Umpqua National Forest were surveyed for non-­native aquatic plants and mussels during August, 2009. A diverse assemblage of native plants was identified ...

  Citation × Citation Citation Abstract Copy Title: Non-­Native Invasive Aquatic Plant and Mussel Survey of Six Umpqua National Forest Area Lakes Author: Sytsma, Mark, Miller, Rich, Shrestha, Rupa Year: 2010 Six lakes and ponds located within or near the Umpqua National Forest were surveyed for non-­native aquatic plants and mussels during August, 2009. A diverse assemblage of native plants was identified along with one possible non-­native aquatic plant hybrid in Herberts Pond. The possible hybrid between the non-­native species Myriophyllum spicatum and the native species M. sibiricum requires genetic analysis for identification. Water chemistry is suitable for the establishment of invasive mussels in Buckeye Lake; however, no zebra or quagga mussel veligers were detected in any of the lakes. Title: Non-­Native Invasive Aquatic Plant and Mussel Survey of Six Umpqua National Forest Area Lakes Author: Sytsma, Mark, Miller, Rich, Shrestha, Rupa Year: 2010 Six lakes and ponds located within or near the Umpqua National Forest were surveyed for non-­native aquatic plants and mussels during August, 2009. A diverse assemblage of native plants was identified along with one possible non-­native aquatic plant hybrid in Herberts Pond. The possible hybrid between the non-­native species Myriophyllum spicatum and the native species M. sibiricum requires genetic analysis for identification. Water chemistry is suitable for the establishment of invasive mussels in Buckeye Lake; however, no zebra or quagga mussel veligers were detected in any of the lakes. Close

• 34. [Image] Malheur, Lower Klamath Lake, and Hart Mountain Refuges, 1930-1935

  	Correspondence, articles drafts, and notes discussing the Malheur Lake and Lower Klamath Lake Refuges with a focus on the impact of agricultural projects on the reservations, including water shortages ...
  	Citation × Citation Citation Abstract Copy Title: Malheur, Lower Klamath Lake, and Hart Mountain Refuges, 1930-1935 Author: Washington (State). Department of Agriculture; Simpson, Gene M.; Ickes, Harold L. (Harold LeClair), 1874-1952; Amory, Copley; Finley, William L. (William Lovell), 1876-1953 Year: 1930 Correspondence, articles drafts, and notes discussing the Malheur Lake and Lower Klamath Lake Refuges with a focus on the impact of agricultural projects on the reservations, including water shortages and pollution. Additional topics include concerns about an antelope population limit at the Hart Mountain Game Refuge and the introduction of non-native species to replace dwindling native bird and fish populations. Title: Malheur, Lower Klamath Lake, and Hart Mountain Refuges, 1930-1935 Author: Washington (State). Department of Agriculture; Simpson, Gene M.; Ickes, Harold L. (Harold LeClair), 1874-1952; Amory, Copley; Finley, William L. (William Lovell), 1876-1953 Year: 1930 Correspondence, articles drafts, and notes discussing the Malheur Lake and Lower Klamath Lake Refuges with a focus on the impact of agricultural projects on the reservations, including water shortages and pollution. Additional topics include concerns about an antelope population limit at the Hart Mountain Game Refuge and the introduction of non-native species to replace dwindling native bird and fish populations. Close

• 35. [Article] Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary

  In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, ...

  Citation × Citation Citation Abstract Copy Title: Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary Author: Kidd, Sarah Ann Year: 2017 In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, salinity levels). How these controls influence the success of tidal wetland restoration are only partly understood, but have important implications for wetland habitat recovery. Specifically, the extent to which the existing native and non-native seed banks in tidally reconnected wetlands interact with these controls is not clear, yet the potential success of passive restoration methods depends upon this understanding. For a 54-year chronosequence of eleven tidal wetland restoration sites in the Lower Columbia River of western Oregon, USA, it was hypothesized that native plant species and soil properties would show trends approaching reference levels within 3 to 20 years post-restoration and that lower elevation wetland areas within restored sites would exhibit a greater native species abundance and similarity to reference sites, compared with restored high elevation wetland areas. Results indicated that plant species richness, soil organic matter, bulk density, pH, and salinity conditions among the restoration sites reached reference wetland ranges within 3-6 years post-tidal reconnection. The mid-low marsh elevation zones (2.5 m) remained dominated by non-native species Phalaris arundinacea and Juncus effusus subsp. effusus. To investigate the mechanisms driving these non-native plant invasions, it was hypothesized that native and non-native wetland plant community distributions would be reflective both of their abundance in the seed bank and of their germination tolerance to wetland tidal flooding and salinity conditions. Using a factorial study design of three tidal conditions by three salinity levels, these hypotheses were tested in the greenhouse. Overall, non-native seeds were found to significantly outnumber native seeds in both seed banks. In the greenhouse, P. arundinacea and J. effusus were found to germinate more readily out of the seed bank under freshwater high-marsh flooding (1 hour a day) treatments as compared to oligohaline (3 ppt) mid-low marsh flooding (3-6 hours twice a day) treatments and to brackish salinity (10 ppt) treatments. Dominant native wetland species, Carex lyngbyei and Schoenoplectus lacustris, germination were not found to vary significantly among the treatments (p > 0.10). These results indicate that the salinity and flooding gradients within these restored marshes suppress germination of the non-native species in the low-mid marsh but not in the high marsh, where they are likely able to outcompete the native species due to their dominance in the seed bank. The implications of these results for passive tidal wetland restoration efforts are that both seed bank composition and species-specific tolerances to restored tidal flooding and salinity gradients are key mechanisms driving native and non-native plant community development and resilience. Title: Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary Author: Kidd, Sarah Ann Year: 2017 In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, salinity levels). How these controls influence the success of tidal wetland restoration are only partly understood, but have important implications for wetland habitat recovery. Specifically, the extent to which the existing native and non-native seed banks in tidally reconnected wetlands interact with these controls is not clear, yet the potential success of passive restoration methods depends upon this understanding. For a 54-year chronosequence of eleven tidal wetland restoration sites in the Lower Columbia River of western Oregon, USA, it was hypothesized that native plant species and soil properties would show trends approaching reference levels within 3 to 20 years post-restoration and that lower elevation wetland areas within restored sites would exhibit a greater native species abundance and similarity to reference sites, compared with restored high elevation wetland areas. Results indicated that plant species richness, soil organic matter, bulk density, pH, and salinity conditions among the restoration sites reached reference wetland ranges within 3-6 years post-tidal reconnection. The mid-low marsh elevation zones (2.5 m) remained dominated by non-native species Phalaris arundinacea and Juncus effusus subsp. effusus. To investigate the mechanisms driving these non-native plant invasions, it was hypothesized that native and non-native wetland plant community distributions would be reflective both of their abundance in the seed bank and of their germination tolerance to wetland tidal flooding and salinity conditions. Using a factorial study design of three tidal conditions by three salinity levels, these hypotheses were tested in the greenhouse. Overall, non-native seeds were found to significantly outnumber native seeds in both seed banks. In the greenhouse, P. arundinacea and J. effusus were found to germinate more readily out of the seed bank under freshwater high-marsh flooding (1 hour a day) treatments as compared to oligohaline (3 ppt) mid-low marsh flooding (3-6 hours twice a day) treatments and to brackish salinity (10 ppt) treatments. Dominant native wetland species, Carex lyngbyei and Schoenoplectus lacustris, germination were not found to vary significantly among the treatments (p > 0.10). These results indicate that the salinity and flooding gradients within these restored marshes suppress germination of the non-native species in the low-mid marsh but not in the high marsh, where they are likely able to outcompete the native species due to their dominance in the seed bank. The implications of these results for passive tidal wetland restoration efforts are that both seed bank composition and species-specific tolerances to restored tidal flooding and salinity gradients are key mechanisms driving native and non-native plant community development and resilience. Close

• 36. [Article] Progress Reports 2004: 2004 Oregon Chub Investigations

  Abstract -- Oregon chub are endemic to the Willamette River drainage of western Oregon (Markle et al. 1991). This species was formerly distributed throughout the Willamette River Valley (Snyder 1908) in ...

  Citation × Citation Citation Abstract Copy Title: Progress Reports 2004: 2004 Oregon Chub Investigations Abstract -- Oregon chub are endemic to the Willamette River drainage of western Oregon (Markle et al. 1991). This species was formerly distributed throughout the Willamette River Valley (Snyder 1908) in off-channel habitats such as beaver ponds, oxbows, stable backwater sloughs, and flooded marshes. These habitats usually have little or no water flow, have silty and organic substrate, and have an abundance of aquatic vegetation and cover for hiding and spawning. In the last 100 years, off-channel habitats have disappeared because of changes in seasonal flows resulting from the construction of dams throughout the basin, channelization of the Willamette River and its tributaries, and agricultural practices. This loss of habitat combined with the introduction of non-native species to the Willamette Valley resulted in a sharp decline in Oregon chub abundance. The reduction of habitat and the restricted distribution of the Oregon chub resulted in a determination of "endangered" status under the federal endangered species act (Markle and Pearsons 1990; Rhew 1993). To evaluate Oregon chub population abundance and distribution, the Oregon Department of Fish and Wildlife conducted surveys in April-October 2004. We conducted similar surveys in 1991-2003 (Scheerer et. al. 1992; 1993; 1994; 1995; 1996; 1998; 1999; 2000; 2001; 2002; 2003; 2004; Scheerer and Jones 1997). The survey objectives were to collect information on the status, distribution, and abundance of Oregon chub, the presence of non-native and native species, the characteristics of Oregon chub habitats, the characteristics of potential introduction sites, and to evaluate the success of Oregon chub introductions. In addition, we reviewed and evaluated projects and activities with the potential to impact Oregon chub and their habitats and provided summaries to the U.S. Fish and Wildlife Service. Title: Progress Reports 2004: 2004 Oregon Chub Investigations Abstract -- Oregon chub are endemic to the Willamette River drainage of western Oregon (Markle et al. 1991). This species was formerly distributed throughout the Willamette River Valley (Snyder 1908) in off-channel habitats such as beaver ponds, oxbows, stable backwater sloughs, and flooded marshes. These habitats usually have little or no water flow, have silty and organic substrate, and have an abundance of aquatic vegetation and cover for hiding and spawning. In the last 100 years, off-channel habitats have disappeared because of changes in seasonal flows resulting from the construction of dams throughout the basin, channelization of the Willamette River and its tributaries, and agricultural practices. This loss of habitat combined with the introduction of non-native species to the Willamette Valley resulted in a sharp decline in Oregon chub abundance. The reduction of habitat and the restricted distribution of the Oregon chub resulted in a determination of "endangered" status under the federal endangered species act (Markle and Pearsons 1990; Rhew 1993). To evaluate Oregon chub population abundance and distribution, the Oregon Department of Fish and Wildlife conducted surveys in April-October 2004. We conducted similar surveys in 1991-2003 (Scheerer et. al. 1992; 1993; 1994; 1995; 1996; 1998; 1999; 2000; 2001; 2002; 2003; 2004; Scheerer and Jones 1997). The survey objectives were to collect information on the status, distribution, and abundance of Oregon chub, the presence of non-native and native species, the characteristics of Oregon chub habitats, the characteristics of potential introduction sites, and to evaluate the success of Oregon chub introductions. In addition, we reviewed and evaluated projects and activities with the potential to impact Oregon chub and their habitats and provided summaries to the U.S. Fish and Wildlife Service. Close

• 37. [Article] Evaluating taxonomic homogenization of freshwater fish assemblages in Chile

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by SpringerOpen. The published article can be found at: http://link.springer.com/journal/40693

  Citation × Citation Citation Abstract Copy Title: Evaluating taxonomic homogenization of freshwater fish assemblages in Chile Author: Arismendi, Ivan, Gomez-Uchida, Daniel, Vargas, Pamela V. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by SpringerOpen. The published article can be found at: http://link.springer.com/journal/40693 Title: Evaluating taxonomic homogenization of freshwater fish assemblages in Chile Author: Arismendi, Ivan, Gomez-Uchida, Daniel, Vargas, Pamela V. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by SpringerOpen. The published article can be found at: http://link.springer.com/journal/40693 Close

• 38. [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

• 39. [Article] Potential of eradicating noxious weed seeds from the soil with heat and carabid seed predators

  The goal of this project was to develop and test non-herbicidal techniques that remove nonnative plant or weed seeds from the top 2 inches of the soil. The Nature Conservancy (TNC) is currently restoring ...

  Citation × Citation Citation Abstract Copy Title: Potential of eradicating noxious weed seeds from the soil with heat and carabid seed predators Author: Marshall, Nicole S. The goal of this project was to develop and test non-herbicidal techniques that remove nonnative plant or weed seeds from the top 2 inches of the soil. The Nature Conservancy (TNC) is currently restoring prairies in the Willamette Valley. Some areas of the Pacific Northwest have already seen loss of more than 99% of former native prairie and 90% oak savanna to agriculture, forest production, and development. In order for the land to be restored, all non-native vegetation must be removed, beginning with removal of unwanted vegetation and a reduction of weed seed density in the soil (Greg Fitzpatrick, 2006). Non-native or invasive plant species pose a serious threat to revegetation with native species, and the cost of weed management is prohibitive if herbicides are not used. We tested two strategies to remove weed seeds from the soil. In the first project we worked collaboratively with mechanical engineering (ME) students to develop a machine that would kill seeds in the soil with heat. We tested weed seed survival after exposure to various temperatures and provided the data to the ME students that so that they could adequately design and build the machine. We also evaluated the efficacy of their machine after it was built. In the second project we measured the potential seed loss due to carabid beetle weed seed predation in a controlled environment. The non-native species of choice for these studies represented a broad range of environmental adaptability and included Pigweed (Aamaranthus retroflexus), Oxeye Daisy (Chysanthemum leucanthemum), Wild Carrot (Daucus carota), and False Brome (Brachypodium sylvaticum), Proso Millet (Panicum miliaceum), Hairy Nightshade (Solanaceae) or (Solanum sarrachoides) (see appendix I for more information on the characteristics of these species). Title: Potential of eradicating noxious weed seeds from the soil with heat and carabid seed predators Author: Marshall, Nicole S. The goal of this project was to develop and test non-herbicidal techniques that remove nonnative plant or weed seeds from the top 2 inches of the soil. The Nature Conservancy (TNC) is currently restoring prairies in the Willamette Valley. Some areas of the Pacific Northwest have already seen loss of more than 99% of former native prairie and 90% oak savanna to agriculture, forest production, and development. In order for the land to be restored, all non-native vegetation must be removed, beginning with removal of unwanted vegetation and a reduction of weed seed density in the soil (Greg Fitzpatrick, 2006). Non-native or invasive plant species pose a serious threat to revegetation with native species, and the cost of weed management is prohibitive if herbicides are not used. We tested two strategies to remove weed seeds from the soil. In the first project we worked collaboratively with mechanical engineering (ME) students to develop a machine that would kill seeds in the soil with heat. We tested weed seed survival after exposure to various temperatures and provided the data to the ME students that so that they could adequately design and build the machine. We also evaluated the efficacy of their machine after it was built. In the second project we measured the potential seed loss due to carabid beetle weed seed predation in a controlled environment. The non-native species of choice for these studies represented a broad range of environmental adaptability and included Pigweed (Aamaranthus retroflexus), Oxeye Daisy (Chysanthemum leucanthemum), Wild Carrot (Daucus carota), and False Brome (Brachypodium sylvaticum), Proso Millet (Panicum miliaceum), Hairy Nightshade (Solanaceae) or (Solanum sarrachoides) (see appendix I for more information on the characteristics of these species). Close

• 40. [Article] Effects of wildfire burn severity on soil microbial communities and invasive plant species in the Cascade Range of Oregon

  Fire suppression in the last several decades has resulted in unprecedented accumulations of organic matter on the landscape, leading to an increase in large, intense wildfires. This study investigated ...

  Citation × Citation Citation Abstract Copy Title: Effects of wildfire burn severity on soil microbial communities and invasive plant species in the Cascade Range of Oregon Author: Hebel, Cassie L. Fire suppression in the last several decades has resulted in unprecedented accumulations of organic matter on the landscape, leading to an increase in large, intense wildfires. This study investigated the soil microbial community (using phospholipid fatty acid analysis) across recently burned forests on the eastern slope of the Cascade Range in Oregon to examine the effects this belowground community has on the growth of native and non-native plant species in severely burned “red” soil and in less severely burned “black” soil. Long duration, smoldering conditions creating red soils drastically altered both soil nutrients and microbial community structure. Changes in soil properties and biota affected plant growth in a controlled growth chamber, as well as vegetative colonization on red soil plots in natural field conditions. Differential growth was observed between native and non-native plant species when grown in soil from the two burn severities. Native plant growth did not differ between black and red soil, while non-native plants showed reduced growth in red soil. Although it previously had been reported that fire increased the likelihood of invasion by non-native plant species in a burn area, these results do not support the notion that red soil conditions are more susceptible than moderately burned soil to non-native, invasive plant species colonization. While many factors in addition to mycorrhizal colonization and burn severity influence plant growth, such as soil nutrient availability, our results suggest that a variety of strategies allow plants to grow in disturbed environments. Continued monitoring of microbial communities and re-vegetation in red soil sites could further our understanding of the length of post-fire recovery time of severely burned red soil. Title: Effects of wildfire burn severity on soil microbial communities and invasive plant species in the Cascade Range of Oregon Author: Hebel, Cassie L. Fire suppression in the last several decades has resulted in unprecedented accumulations of organic matter on the landscape, leading to an increase in large, intense wildfires. This study investigated the soil microbial community (using phospholipid fatty acid analysis) across recently burned forests on the eastern slope of the Cascade Range in Oregon to examine the effects this belowground community has on the growth of native and non-native plant species in severely burned “red” soil and in less severely burned “black” soil. Long duration, smoldering conditions creating red soils drastically altered both soil nutrients and microbial community structure. Changes in soil properties and biota affected plant growth in a controlled growth chamber, as well as vegetative colonization on red soil plots in natural field conditions. Differential growth was observed between native and non-native plant species when grown in soil from the two burn severities. Native plant growth did not differ between black and red soil, while non-native plants showed reduced growth in red soil. Although it previously had been reported that fire increased the likelihood of invasion by non-native plant species in a burn area, these results do not support the notion that red soil conditions are more susceptible than moderately burned soil to non-native, invasive plant species colonization. While many factors in addition to mycorrhizal colonization and burn severity influence plant growth, such as soil nutrient availability, our results suggest that a variety of strategies allow plants to grow in disturbed environments. Continued monitoring of microbial communities and re-vegetation in red soil sites could further our understanding of the length of post-fire recovery time of severely burned red soil. Close