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• 31. [Article] Two thinnings of douglas-fir with crawler tractors : time differences

  Two intermediate cuttings were made in a Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stand on the Wilark forest management research area in northwestern Oregon. Age of trees in the stand varied ...

  Citation × Citation Citation Abstract Copy Title: Two thinnings of douglas-fir with crawler tractors : time differences Author: Kangur, Rudolf, Oregon State University. Forest Research Laboratory Two intermediate cuttings were made in a Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stand on the Wilark forest management research area in northwestern Oregon. Age of trees in the stand varied from 47 to 62 years at the first cutting. Crawler tractors were used in both extractions. In the first cutting, the time required for log production was 6.21 man-hours for a thousand board feet Scribner log rule at the mill site on the area. An additional 1.01 man-hours a thousand board feet was accounted for in delays not associated with productive time. A total of 19,702 feet of road was constructed. Construction time for 100 feet of road ranged from 1.55 man-hours for skid roads to 9.39 manhours for main road. Road construction increased total time for log production by 0.92 man-hour for a thousand board feet in the first cutting. The time required for log production in the second cutting was 3.78 man-hours for a thousand board feet, and delays amounted to 0.43 man-hour a thousand. A separate time study was made to determine the influence of delays present in the actual extractions on the cost of log production. Frequently ignored factors that appeared to affect economic outcome were favorable weather, efficient technique in extraction, and skilled labor. Title: Two thinnings of douglas-fir with crawler tractors : time differences Author: Kangur, Rudolf, Oregon State University. Forest Research Laboratory Two intermediate cuttings were made in a Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stand on the Wilark forest management research area in northwestern Oregon. Age of trees in the stand varied from 47 to 62 years at the first cutting. Crawler tractors were used in both extractions. In the first cutting, the time required for log production was 6.21 man-hours for a thousand board feet Scribner log rule at the mill site on the area. An additional 1.01 man-hours a thousand board feet was accounted for in delays not associated with productive time. A total of 19,702 feet of road was constructed. Construction time for 100 feet of road ranged from 1.55 man-hours for skid roads to 9.39 manhours for main road. Road construction increased total time for log production by 0.92 man-hour for a thousand board feet in the first cutting. The time required for log production in the second cutting was 3.78 man-hours for a thousand board feet, and delays amounted to 0.43 man-hour a thousand. A separate time study was made to determine the influence of delays present in the actual extractions on the cost of log production. Frequently ignored factors that appeared to affect economic outcome were favorable weather, efficient technique in extraction, and skilled labor. Close

• 32. [Article] Heuristic solution techniques for a spatial harvest scheduling problem involving wildlife habitat and timber income

  Three heuristic techniques: simulated annealing (SA), tabu search (TS), and tabu search with strategic oscillation (TSSO), were used to schedule silvicultural activities designed to accelerate development ...

  Citation × Citation Citation Abstract Copy Title: Heuristic solution techniques for a spatial harvest scheduling problem involving wildlife habitat and timber income Author: Sharer, Brian K. Three heuristic techniques: simulated annealing (SA), tabu search (TS), and tabu search with strategic oscillation (TSSO), were used to schedule silvicultural activities designed to accelerate development of older forest structure at both stand and landscape scales over a 2450 acre forest located in northwestern Oregon. Goals for the forest over a 100-year planning horizon included reaching at least 500 acres of older forest structure with at least one contiguous 200-acre (or larger) block as soon as possible. The configuration and location, but not the amounts, of the older forest structure acres and the contiguous block were then free to move about the forest through time while best meeting the goal of producing a high, steady revenue flow over the entire planning horizon subject to restrictions on maximum clearcut patch size. The heuristic techniques were able to provide feasible tactical schedules fulfilling the strategic goals over the entire horizon in ways which traditional forest planning tools cannot. Of the three techniques examined, TSSO produced schedules with the best, most consistent objective function values. SA yielded a wider range of values which were always slightly worse but required only a fraction of the computing time. Straightforward TS produced relatively poor objective function values, most likely because of its inability to search the infeasible regions of the diverse solution space. Estimation of the globally optimal objective function value using Weibull distributions suggested that all TSSO solutions were within 1.8% of the optimum, the best being within .03%, while all SA solutions were within 7.6%, the best being within 1 .7%. However, 95% confidence intervals of the Weibull location parameter estimates for the SA and TSSO distributions did not overlap, despite the fact that both distributions of results failed to be rejected as fitting a Weibull distribution. This disparity again suggests that statistical inference by itself of global optima for heuristic results may be an inadequate means of assessing how "good" a heuristic is. Title: Heuristic solution techniques for a spatial harvest scheduling problem involving wildlife habitat and timber income Author: Sharer, Brian K. Three heuristic techniques: simulated annealing (SA), tabu search (TS), and tabu search with strategic oscillation (TSSO), were used to schedule silvicultural activities designed to accelerate development of older forest structure at both stand and landscape scales over a 2450 acre forest located in northwestern Oregon. Goals for the forest over a 100-year planning horizon included reaching at least 500 acres of older forest structure with at least one contiguous 200-acre (or larger) block as soon as possible. The configuration and location, but not the amounts, of the older forest structure acres and the contiguous block were then free to move about the forest through time while best meeting the goal of producing a high, steady revenue flow over the entire planning horizon subject to restrictions on maximum clearcut patch size. The heuristic techniques were able to provide feasible tactical schedules fulfilling the strategic goals over the entire horizon in ways which traditional forest planning tools cannot. Of the three techniques examined, TSSO produced schedules with the best, most consistent objective function values. SA yielded a wider range of values which were always slightly worse but required only a fraction of the computing time. Straightforward TS produced relatively poor objective function values, most likely because of its inability to search the infeasible regions of the diverse solution space. Estimation of the globally optimal objective function value using Weibull distributions suggested that all TSSO solutions were within 1.8% of the optimum, the best being within .03%, while all SA solutions were within 7.6%, the best being within 1 .7%. However, 95% confidence intervals of the Weibull location parameter estimates for the SA and TSSO distributions did not overlap, despite the fact that both distributions of results failed to be rejected as fitting a Weibull distribution. This disparity again suggests that statistical inference by itself of global optima for heuristic results may be an inadequate means of assessing how "good" a heuristic is. Close

• 33. [Article] Preliminary report on the geology of the Molalla quadrangle, Oregon

  The Molalla quadrangle is located in northwestern Oregon along the eastern edge of Willamette Valley about 30 miles south of Portland. The area includes part of the Western Cascade foothills as well as ...

  Citation × Citation Citation Abstract Copy Title: Preliminary report on the geology of the Molalla quadrangle, Oregon Author: Harper, Herbert Ewing The Molalla quadrangle is located in northwestern Oregon along the eastern edge of Willamette Valley about 30 miles south of Portland. The area includes part of the Western Cascade foothills as well as a portion of the Willamette Valley lowland. The rocks in the Cascade foothills are marine and terrestrial sediments interlayered with volcanic flows and pyroclastics which range from Eocene (?) to Pliocene or early Pleistocene in age. The oldest rocks consist of approximately 1500 feet of basaltic and andesitic lavas, present in the southeastern portion of the area, and described here as the Pre-Butte Creek lavas. The base or lower part of the series contains interbedded marine pebble conglomerates presumably of Eocene age. To the southwest the laves are unconformably ever-lain with about 1200 feet of marine and terrestrial sediments which have been termed the Butte Creek beds. Field relations indicate a correlation of these sediments with the Oligocene Illahe sandstone, while the faunal study made by Durham suggests a lower Miocene age. In the southwestern part of the quadrangle the Butte Creek beds are unconformably overlain by the middle Miocene Stayton lavas. Several hundred feet of pyroclastics and terrestrial sediments considered early Pliocene in age and described as the Molalla formation are exposed along Molalla River in the eastern and northeastern part of the quadrangle. They rest unconformably on the Pre-Butte Creek lavas and are overlain by Pliocene or early Pleistocene Boring lavas. Where exposed along the western edge of the Cascade foothills these older formations are covered by middle Pleistocene alluvial deposits which blanket the Willamette valley lowland. All of the Tertiary rocks have been tilted or gently folded. Dips observed in the Butte Creek beds in the southern half of the area average about 6 degrees and indicate an elongate domal fold trending northeasterly. A regional dip of 5 to 8 degrees to the northwest is present in the Molallla formation in the northern part of the area. Minor normal faulting in present locally in the Butte Creek beds. Residual and transported high-alumina clays are present in the Molalla formation. Exploration by the United States Bureau of Mines and Unites States Geological Survey revealed an estimated 53,460,000 wet tons of ore in the Molalla area. Title: Preliminary report on the geology of the Molalla quadrangle, Oregon Author: Harper, Herbert Ewing The Molalla quadrangle is located in northwestern Oregon along the eastern edge of Willamette Valley about 30 miles south of Portland. The area includes part of the Western Cascade foothills as well as a portion of the Willamette Valley lowland. The rocks in the Cascade foothills are marine and terrestrial sediments interlayered with volcanic flows and pyroclastics which range from Eocene (?) to Pliocene or early Pleistocene in age. The oldest rocks consist of approximately 1500 feet of basaltic and andesitic lavas, present in the southeastern portion of the area, and described here as the Pre-Butte Creek lavas. The base or lower part of the series contains interbedded marine pebble conglomerates presumably of Eocene age. To the southwest the laves are unconformably ever-lain with about 1200 feet of marine and terrestrial sediments which have been termed the Butte Creek beds. Field relations indicate a correlation of these sediments with the Oligocene Illahe sandstone, while the faunal study made by Durham suggests a lower Miocene age. In the southwestern part of the quadrangle the Butte Creek beds are unconformably overlain by the middle Miocene Stayton lavas. Several hundred feet of pyroclastics and terrestrial sediments considered early Pliocene in age and described as the Molalla formation are exposed along Molalla River in the eastern and northeastern part of the quadrangle. They rest unconformably on the Pre-Butte Creek lavas and are overlain by Pliocene or early Pleistocene Boring lavas. Where exposed along the western edge of the Cascade foothills these older formations are covered by middle Pleistocene alluvial deposits which blanket the Willamette valley lowland. All of the Tertiary rocks have been tilted or gently folded. Dips observed in the Butte Creek beds in the southern half of the area average about 6 degrees and indicate an elongate domal fold trending northeasterly. A regional dip of 5 to 8 degrees to the northwest is present in the Molallla formation in the northern part of the area. Minor normal faulting in present locally in the Butte Creek beds. Residual and transported high-alumina clays are present in the Molalla formation. Exploration by the United States Bureau of Mines and Unites States Geological Survey revealed an estimated 53,460,000 wet tons of ore in the Molalla area. Close

• 34. [Article] Removing traffic emissions from CO₂ time series measured at a tall tower using mobile measurements and transport modeling

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/atmospheric-envi...

  Citation × Citation Citation Abstract Copy Title: Removing traffic emissions from CO₂ time series measured at a tall tower using mobile measurements and transport modeling Author: Rella, Chris W., Law, Beverly E., Schmidt, Andres, Göckede, Mathias, Yang, Zhenlin, Hanson, Chad This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/atmospheric-environment/ Title: Removing traffic emissions from CO₂ time series measured at a tall tower using mobile measurements and transport modeling Author: Rella, Chris W., Law, Beverly E., Schmidt, Andres, Göckede, Mathias, Yang, Zhenlin, Hanson, Chad This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/atmospheric-environment/ Close

• 35. [Article] A system analysis method for water quality management by flow augmentation

  A rapid expansion of population and industrialization in recent years has created new and difficult problems in water resources management. Prudent management of water quality will require that more efficient ...

  Citation × Citation Citation Abstract Copy Title: A system analysis method for water quality management by flow augmentation Author: Worley, John Larry A rapid expansion of population and industrialization in recent years has created new and difficult problems in water resources management. Prudent management of water quality will require that more efficient methods be developed for evaluating large volumes of data on complex river systems, and tabulating the results in a form readily usable by the persons responsible for decisions. The digital computer is the most promising tool for rapid analysis of these complex water problems. The objective of this thesis is the development of a digital computer program which will investigate the dissolved oxygen relationships in flowing streams and provide for automatic adjustment of flows to maintain minimum dissolved oxygen requirements. The computer program herein developed was applied to the Willamette River Basin in Northwestern Oregon to illustrate its use, but it is general in character so that it may be applied to any drainage basin. Three orders of streams including not more than sixty lengths of river (reaches) may be considered in any given study by a computer with sixty thousand digits of core storage. Limitations on the size of the river system which may be considered are imposed by computer storage capacity above the forty thousand digits needed for program use. The results of this study indicate that: 1. A digital computer using the program developed can, in a few minutes, complete an analysis which would require many man hours of manual computation time. 2. The digital computer program developed is a useful tool for investigating the oxygen relationships existing in a river system under present loadings and flows and for predicting the conditions that will be encountered under future loadings. 3. A computer program of this type could be adapted to nearly any of the quality parameters normally considered or possibly a combination of several parameters at such time as mathematical formulations describing their behavior in streams are available. Title: A system analysis method for water quality management by flow augmentation Author: Worley, John Larry A rapid expansion of population and industrialization in recent years has created new and difficult problems in water resources management. Prudent management of water quality will require that more efficient methods be developed for evaluating large volumes of data on complex river systems, and tabulating the results in a form readily usable by the persons responsible for decisions. The digital computer is the most promising tool for rapid analysis of these complex water problems. The objective of this thesis is the development of a digital computer program which will investigate the dissolved oxygen relationships in flowing streams and provide for automatic adjustment of flows to maintain minimum dissolved oxygen requirements. The computer program herein developed was applied to the Willamette River Basin in Northwestern Oregon to illustrate its use, but it is general in character so that it may be applied to any drainage basin. Three orders of streams including not more than sixty lengths of river (reaches) may be considered in any given study by a computer with sixty thousand digits of core storage. Limitations on the size of the river system which may be considered are imposed by computer storage capacity above the forty thousand digits needed for program use. The results of this study indicate that: 1. A digital computer using the program developed can, in a few minutes, complete an analysis which would require many man hours of manual computation time. 2. The digital computer program developed is a useful tool for investigating the oxygen relationships existing in a river system under present loadings and flows and for predicting the conditions that will be encountered under future loadings. 3. A computer program of this type could be adapted to nearly any of the quality parameters normally considered or possibly a combination of several parameters at such time as mathematical formulations describing their behavior in streams are available. Close

• 36. [Article] Habitat selection by juvenile Swainson’s thrushes (Catharus ustulatus) in headwater riparian areas, Northwestern Oregon, USA

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Habitat selection by juvenile Swainson’s thrushes (Catharus ustulatus) in headwater riparian areas, Northwestern Oregon, USA Author: Jenkins, Stephanie R., Huso, Manuela M., Betts, Matthew G., Hagar, Joan C. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/. Title: Habitat selection by juvenile Swainson’s thrushes (Catharus ustulatus) in headwater riparian areas, Northwestern Oregon, USA Author: Jenkins, Stephanie R., Huso, Manuela M., Betts, Matthew G., Hagar, Joan C. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/. Close

• 37. [Article] A Multi-Year Longitudinal Study of Water Quality Parameters in Four Salmon-Bearing and Recreational Streams on Mount Hood, Oregon

  This is the publisher’s final pdf. The published article is copyrighted by Public Library of Science and can be found at: http://www.plos.org/.

  Citation × Citation Citation Abstract Copy Title: A Multi-Year Longitudinal Study of Water Quality Parameters in Four Salmon-Bearing and Recreational Streams on Mount Hood, Oregon Author: Banet, Nathan, Alexander, David, Kolmes, Elijah, Wasowski, Ronald, Roemer, Derek, Haines, Morgan, Kolmes, Steven, Webber, Sarah, Card, Amy, Northcutt, Kelly This is the publisher’s final pdf. The published article is copyrighted by Public Library of Science and can be found at: http://www.plos.org/. Title: A Multi-Year Longitudinal Study of Water Quality Parameters in Four Salmon-Bearing and Recreational Streams on Mount Hood, Oregon Author: Banet, Nathan, Alexander, David, Kolmes, Elijah, Wasowski, Ronald, Roemer, Derek, Haines, Morgan, Kolmes, Steven, Webber, Sarah, Card, Amy, Northcutt, Kelly This is the publisher’s final pdf. The published article is copyrighted by Public Library of Science and can be found at: http://www.plos.org/. Close

• 38. [Article] Using Tabu Search to solve tactical forest planning problems with spatial wildlife habitat goals and constraints

  A method was developed to formulate and solve a fifty-year tactical harvest scheduling problem that included spatial wildlife habitat goals and constraints for a 4800-acre watershed in Northwestern Oregon ...

  Citation × Citation Citation Abstract Copy Title: Using Tabu Search to solve tactical forest planning problems with spatial wildlife habitat goals and constraints Author: Boston, Kevin Donald A method was developed to formulate and solve a fifty-year tactical harvest scheduling problem that included spatial wildlife habitat goals and constraints for a 4800-acre watershed in Northwestern Oregon under four scenarios. Three goals and two habitat constraints were included in each scenario. The first goal was a volume goal. The second goal was a landscape aggregation goal measured with the contagion index. The third goal was a shape goal using the ratio of the existing perimeter of closed-canopy stands with that of a circle with equivalent area. The first constraint required a minimum cluster of connected closed-canopy stands that spanned opposite edges of a map. The second constraint limited the maximum opening created in any period. The algorithm included both fixed and variable cost components for the transportation network. Tabu Search with both short-term memory restriction and a long-term diversification strategy was used to solve this ten-period problem. The performance of the heuristic was measured by comparing the results with an estimate of the optimal value obtained from extreme value theory using a three-parameter Weibull distribution. In scenario one, the shape goal was reached in most periods and the average contagion index was 0.35. The volume goal was met or exceeded in all periods. The heuristic found one solution within 2 percent of the estimated optimal value, while 75 percent of the solutions were within 80 percent of the estimated optimal value. In scenario two, the average contagion index was 0.40. The goal was met in over 50 percent of the periods. The volume and shape goals were met or exceeded in all periods. The heuristic found one solution within 6 percent of the estimated optimal value, while the remaining solutions were within 83 percent of the estimated optimal value. Two additional scenarios were developed to create specific wildlife habitat. Scenario three developed high quality habitat for pine marten containing a connected landscape of closed-canopy stands with minimum edge habitat. Scenario four was developed for elk. This analysis produced habitat with a mixture of open and closed-canopy stands in a dispersed pattern. Title: Using Tabu Search to solve tactical forest planning problems with spatial wildlife habitat goals and constraints Author: Boston, Kevin Donald A method was developed to formulate and solve a fifty-year tactical harvest scheduling problem that included spatial wildlife habitat goals and constraints for a 4800-acre watershed in Northwestern Oregon under four scenarios. Three goals and two habitat constraints were included in each scenario. The first goal was a volume goal. The second goal was a landscape aggregation goal measured with the contagion index. The third goal was a shape goal using the ratio of the existing perimeter of closed-canopy stands with that of a circle with equivalent area. The first constraint required a minimum cluster of connected closed-canopy stands that spanned opposite edges of a map. The second constraint limited the maximum opening created in any period. The algorithm included both fixed and variable cost components for the transportation network. Tabu Search with both short-term memory restriction and a long-term diversification strategy was used to solve this ten-period problem. The performance of the heuristic was measured by comparing the results with an estimate of the optimal value obtained from extreme value theory using a three-parameter Weibull distribution. In scenario one, the shape goal was reached in most periods and the average contagion index was 0.35. The volume goal was met or exceeded in all periods. The heuristic found one solution within 2 percent of the estimated optimal value, while 75 percent of the solutions were within 80 percent of the estimated optimal value. In scenario two, the average contagion index was 0.40. The goal was met in over 50 percent of the periods. The volume and shape goals were met or exceeded in all periods. The heuristic found one solution within 6 percent of the estimated optimal value, while the remaining solutions were within 83 percent of the estimated optimal value. Two additional scenarios were developed to create specific wildlife habitat. Scenario three developed high quality habitat for pine marten containing a connected landscape of closed-canopy stands with minimum edge habitat. Scenario four was developed for elk. This analysis produced habitat with a mixture of open and closed-canopy stands in a dispersed pattern. Close

• 39. [Article] Harvestable moss : communities, hosts, and accumulation

  With the increased recognition of moss as a secondary forest product has come an increased concern for the ecological ramifications of moss harvest. Three issues of primary concern are (1) characterizing ...

  Citation × Citation Citation Abstract Copy Title: Harvestable moss : communities, hosts, and accumulation Author: Peck, JeriLynn E. With the increased recognition of moss as a secondary forest product has come an increased concern for the ecological ramifications of moss harvest. Three issues of primary concern are (1) characterizing the epiphyte communities impacted by harvest, (2) assessing the host preferences of these epiphytes, and (3) describing the availability of harvestable epiphytes. Harvestable epiphytes are generally large mats of clean, green plant material that can be easily accessed and removed from their substrate by a commercial moss harvester. Harvestable epiphytes on tree trunks and shrub stems were sampled at 10 sites in each of the Cascade and Coast Ranges in northwestern Oregon. Frequency of occurrence and biomass are reported for 50 species found in harvestable epiphyte mats, categorized as "target" (7 species), "nontarget" (37 species), and "incidental" (6 species), according to their commercial utility. Target species were more abundant in stands with relatively high hardwood basal area and densities of harvestable epiphyte hosts. Nontarget and incidental species were more abundant on hosts with relatively large surface areas and in stands with relatively high hardwood basal. All species were less abundant in stands with high conifer basal area. Eleven species of hosts, including seven shrubs and four trees, supported harvestable quantities of epiphytes, although most samples were collected from the clonal shrub vine maple (Acer circinatum). Epiphyte mats on tree trunks and shrub stems differed in epiphyte species composition. Relative frequency of occurence and abundance were used to determine host preference by several epiphytes, including Orthotricum lyellii for A. circinatum and Neckera douglasii for Alnus rubra. Harvestable epiphyte biomass ranged from 24 to 1469 kg/ha (dry weight). Biomass is a function of both site quality and availability of suitable hosts. Epiphyte mat accumulation on Acer circinatum was more rapid, and more variable, in the Coast Range sites than in the Cascade Range sites. A model describing the factors influencing epiphyte mat accumulation is proposed and management implications for the harvestable moss resource are discussed. Title: Harvestable moss : communities, hosts, and accumulation Author: Peck, JeriLynn E. With the increased recognition of moss as a secondary forest product has come an increased concern for the ecological ramifications of moss harvest. Three issues of primary concern are (1) characterizing the epiphyte communities impacted by harvest, (2) assessing the host preferences of these epiphytes, and (3) describing the availability of harvestable epiphytes. Harvestable epiphytes are generally large mats of clean, green plant material that can be easily accessed and removed from their substrate by a commercial moss harvester. Harvestable epiphytes on tree trunks and shrub stems were sampled at 10 sites in each of the Cascade and Coast Ranges in northwestern Oregon. Frequency of occurrence and biomass are reported for 50 species found in harvestable epiphyte mats, categorized as "target" (7 species), "nontarget" (37 species), and "incidental" (6 species), according to their commercial utility. Target species were more abundant in stands with relatively high hardwood basal area and densities of harvestable epiphyte hosts. Nontarget and incidental species were more abundant on hosts with relatively large surface areas and in stands with relatively high hardwood basal. All species were less abundant in stands with high conifer basal area. Eleven species of hosts, including seven shrubs and four trees, supported harvestable quantities of epiphytes, although most samples were collected from the clonal shrub vine maple (Acer circinatum). Epiphyte mats on tree trunks and shrub stems differed in epiphyte species composition. Relative frequency of occurence and abundance were used to determine host preference by several epiphytes, including Orthotricum lyellii for A. circinatum and Neckera douglasii for Alnus rubra. Harvestable epiphyte biomass ranged from 24 to 1469 kg/ha (dry weight). Biomass is a function of both site quality and availability of suitable hosts. Epiphyte mat accumulation on Acer circinatum was more rapid, and more variable, in the Coast Range sites than in the Cascade Range sites. A model describing the factors influencing epiphyte mat accumulation is proposed and management implications for the harvestable moss resource are discussed. Close

• 40. [Article] The development of a methodology to study the grief and adjustment processes of parents following the death of a young child

  Purpose of the Study The primary purpose of this investigation was to develop a methodology by which to objectively study and assess the grief and adjustment processes of bereaved parents. An original ...

  Citation × Citation Citation Abstract Copy Title: The development of a methodology to study the grief and adjustment processes of parents following the death of a young child Author: Mayhall, Cheron J. Purpose of the Study The primary purpose of this investigation was to develop a methodology by which to objectively study and assess the grief and adjustment processes of bereaved parents. An original research and counseling instrument, the Parental Bereavement Interview and Rating Scale (PBIRS), was formulated, field-tested in a preliminary study, and revised. In pursuit of this purpose, descriptive data about the grief of parents who lost a young child (1-20 years) due to sudden and unexpected circumstances were obtained and reported. Research Questions The thirteen research questions addressed fall into three main categories: (a) methodological considerations regarding the construction and format of the PBIRS, the protocol for its administration, and the age criteria used for selection of subjects; (b) quantitative data describing the nature of the parental grief and adjustment processes; and (c) descriptive information about the general characteristics of the subject group in comparison to other bereaved parents in the U.S. and Canada. Methodology The PBIRS was administered between January and April, 1982, to 20 bereaved parents residing in northwestern Oregon. The instrument is based on an expanded version of Kubler-Ross' grief-stage theory, exploring the grief and adjustment processes through the stages of Denial, Anger, Guilt, Depression and Adaptation. A retrospective research method was employed to examine and assess the subjects' progression through the bereavement experience. The Pearson product-moment correlation coefficient was computed to determine the test-retest reliability for PBIRS items. The data were further presented in graphic and tabular forms to allow for comparison between various time periods in the grief process, and between different sub-groups of subjects. Findings The research methodology and instrument were field-tested with satisfactory results. The preliminary reliability study showed 85 percent of the items to have test-retest coefficients of correlation significant at the .05 level. The instrument and the protocol for its administration were well-received by subjects and by leaders of self-help groups for bereaved parents. Title: The development of a methodology to study the grief and adjustment processes of parents following the death of a young child Author: Mayhall, Cheron J. Purpose of the Study The primary purpose of this investigation was to develop a methodology by which to objectively study and assess the grief and adjustment processes of bereaved parents. An original research and counseling instrument, the Parental Bereavement Interview and Rating Scale (PBIRS), was formulated, field-tested in a preliminary study, and revised. In pursuit of this purpose, descriptive data about the grief of parents who lost a young child (1-20 years) due to sudden and unexpected circumstances were obtained and reported. Research Questions The thirteen research questions addressed fall into three main categories: (a) methodological considerations regarding the construction and format of the PBIRS, the protocol for its administration, and the age criteria used for selection of subjects; (b) quantitative data describing the nature of the parental grief and adjustment processes; and (c) descriptive information about the general characteristics of the subject group in comparison to other bereaved parents in the U.S. and Canada. Methodology The PBIRS was administered between January and April, 1982, to 20 bereaved parents residing in northwestern Oregon. The instrument is based on an expanded version of Kubler-Ross' grief-stage theory, exploring the grief and adjustment processes through the stages of Denial, Anger, Guilt, Depression and Adaptation. A retrospective research method was employed to examine and assess the subjects' progression through the bereavement experience. The Pearson product-moment correlation coefficient was computed to determine the test-retest reliability for PBIRS items. The data were further presented in graphic and tabular forms to allow for comparison between various time periods in the grief process, and between different sub-groups of subjects. Findings The research methodology and instrument were field-tested with satisfactory results. The preliminary reliability study showed 85 percent of the items to have test-retest coefficients of correlation significant at the .05 level. The instrument and the protocol for its administration were well-received by subjects and by leaders of self-help groups for bereaved parents. Close