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• 71. [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

• 72. [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

• 73. [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

• 74. [Article] Wood density of young-growth western hemlock: relation to ring age, radial growth, stand density, and site quality

  Breast-high stem sections were sampled from 56 western hemlock (Tsuga heterophylla (Raf.) Sarg.) trees growing in 15 plots representing a wide range of tree and site conditions in northwestern Oregon. ...

  Citation × Citation Citation Abstract Copy Title: Wood density of young-growth western hemlock: relation to ring age, radial growth, stand density, and site quality Author: Marshall, D. D., Gartner, B. L., Singleton, R., DeBell, D. S. Breast-high stem sections were sampled from 56 western hemlock (Tsuga heterophylla (Raf.) Sarg.) trees growing in 15 plots representing a wide range of tree and site conditions in northwestern Oregon. Growth and wood density traits of individual rings were measured via X-ray densitometry, and relationships of ring density and its components to age and growth rate were analyzed. Ring density was highest (0.49 g/cm3) near the pith, declined to 0.40 g/cm3 at age 10, remained stable to about age 25, and then increased gradually and remained between 0.43 and 0.44 g/cm3 from age 38 to 45 and beyond. A negative influence of rapid growth on whole ring density was greatest at young ages and diminished with time, becoming nonsignificant beyond age 30. Earlywood density, latewood density, and latewood proportion were all negatively related to ring width at young ages, but by age 21–25, latewood proportion was the only component of ring density that remained significantly diminished by increased growth rate. Residual differences in wood density (after age and growth rate were considered) did not appear to be related to either stand density or site class. Overall, young-growth hemlock trees are relatively uniform in wood density and likely to be more so if grown in intensively managed stands. Title: Wood density of young-growth western hemlock: relation to ring age, radial growth, stand density, and site quality Author: Marshall, D. D., Gartner, B. L., Singleton, R., DeBell, D. S. Breast-high stem sections were sampled from 56 western hemlock (Tsuga heterophylla (Raf.) Sarg.) trees growing in 15 plots representing a wide range of tree and site conditions in northwestern Oregon. Growth and wood density traits of individual rings were measured via X-ray densitometry, and relationships of ring density and its components to age and growth rate were analyzed. Ring density was highest (0.49 g/cm3) near the pith, declined to 0.40 g/cm3 at age 10, remained stable to about age 25, and then increased gradually and remained between 0.43 and 0.44 g/cm3 from age 38 to 45 and beyond. A negative influence of rapid growth on whole ring density was greatest at young ages and diminished with time, becoming nonsignificant beyond age 30. Earlywood density, latewood density, and latewood proportion were all negatively related to ring width at young ages, but by age 21–25, latewood proportion was the only component of ring density that remained significantly diminished by increased growth rate. Residual differences in wood density (after age and growth rate were considered) did not appear to be related to either stand density or site class. Overall, young-growth hemlock trees are relatively uniform in wood density and likely to be more so if grown in intensively managed stands. Close

• 75. [Image] Northwestern Bank (Portland, Oregon)

  	This work was listed on the National Register of Historic Places on September 13, 2000.
  	Citation × Citation Citation Abstract Copy Title: Northwestern Bank (Portland, Oregon) Author: Doyle, Patterson, and Beach (architectural firm, 1911-1914); Doyle, Albert E.; Patterson, William B.; Beach, James G. Year: 1913 This work was listed on the National Register of Historic Places on September 13, 2000. Title: Northwestern Bank (Portland, Oregon) Author: Doyle, Patterson, and Beach (architectural firm, 1911-1914); Doyle, Albert E.; Patterson, William B.; Beach, James G. Year: 1913 This work was listed on the National Register of Historic Places on September 13, 2000. Close

• 76. [Image] Northwestern Bank (Portland, Oregon)

  	This work was listed on the National Register of Historic Places on September 13, 2000.
  	Citation × Citation Citation Abstract Copy Title: Northwestern Bank (Portland, Oregon) Author: Doyle, Patterson, and Beach (architectural firm, 1911-1914); Doyle, Albert E.; Patterson, William B.; Beach, James G. Year: 1913 This work was listed on the National Register of Historic Places on September 13, 2000. Title: Northwestern Bank (Portland, Oregon) Author: Doyle, Patterson, and Beach (architectural firm, 1911-1914); Doyle, Albert E.; Patterson, William B.; Beach, James G. Year: 1913 This work was listed on the National Register of Historic Places on September 13, 2000. Close

• 77. [Image] Northwestern Bank (Portland, Oregon)

  	This work was listed on the National Register of Historic Places on September 13, 2000.
  	Citation × Citation Citation Abstract Copy Title: Northwestern Bank (Portland, Oregon) Author: Doyle, Patterson, and Beach (architectural firm, 1911-1914); Doyle, Albert E.; Patterson, William B.; Beach, James G. Year: 1913 This work was listed on the National Register of Historic Places on September 13, 2000. Title: Northwestern Bank (Portland, Oregon) Author: Doyle, Patterson, and Beach (architectural firm, 1911-1914); Doyle, Albert E.; Patterson, William B.; Beach, James G. Year: 1913 This work was listed on the National Register of Historic Places on September 13, 2000. Close

• 78. [Image] Northwestern Bank (Portland, Oregon)

  	This work was listed on the National Register of Historic Places on September 13, 2000.
  	Citation × Citation Citation Abstract Copy Title: Northwestern Bank (Portland, Oregon) Author: Doyle, Patterson, and Beach (architectural firm, 1911-1914); Doyle, Albert E.; Patterson, William B.; Beach, James G. Year: 1913 This work was listed on the National Register of Historic Places on September 13, 2000. Title: Northwestern Bank (Portland, Oregon) Author: Doyle, Patterson, and Beach (architectural firm, 1911-1914); Doyle, Albert E.; Patterson, William B.; Beach, James G. Year: 1913 This work was listed on the National Register of Historic Places on September 13, 2000. Close

• 79. [Image] Northwestern Bank (Portland, Oregon)

  	This work was listed on the National Register of Historic Places on September 13, 2000.
  	Citation × Citation Citation Abstract Copy Title: Northwestern Bank (Portland, Oregon) Author: Doyle, Patterson, and Beach (architectural firm, 1911-1914); Doyle, Albert E.; Patterson, William B.; Beach, James G. Year: 1913 This work was listed on the National Register of Historic Places on September 13, 2000. Title: Northwestern Bank (Portland, Oregon) Author: Doyle, Patterson, and Beach (architectural firm, 1911-1914); Doyle, Albert E.; Patterson, William B.; Beach, James G. Year: 1913 This work was listed on the National Register of Historic Places on September 13, 2000. Close

• 80. [Image] Northwestern Bank (Portland, Oregon)

  	This work was listed on the National Register of Historic Places on September 13, 2000.
  	Citation × Citation Citation Abstract Copy Title: Northwestern Bank (Portland, Oregon) Author: Doyle, Patterson, and Beach (architectural firm, 1911-1914); Doyle, Albert E.; Patterson, William B.; Beach, James G. Year: 1913 This work was listed on the National Register of Historic Places on September 13, 2000. Title: Northwestern Bank (Portland, Oregon) Author: Doyle, Patterson, and Beach (architectural firm, 1911-1914); Doyle, Albert E.; Patterson, William B.; Beach, James G. Year: 1913 This work was listed on the National Register of Historic Places on September 13, 2000. Close