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• 1. [Article] The valuation and use of site information for Douglas-fir reforestation in Western Oregon : a decision analysis

  Existing forest site maps have been described as "invaluable tools" in forest management. Their, economic value potentially materializes as the summed advantage from better decisions in all phases of forestry. Via ...

  Citation × Citation Citation Abstract Copy Title: The valuation and use of site information for Douglas-fir reforestation in Western Oregon : a decision analysis Author: Schöne, Dieter Hans-Friedrich Existing forest site maps have been described as "invaluable tools" in forest management. Their, economic value potentially materializes as the summed advantage from better decisions in all phases of forestry. Via Bayesian decision analysis, this study establishes optimal use and economic value of site information for one facet of management only: The choice of an optimal planting density in Douglas-fir reforestation. Two case studies were undertaken in extremely different environments of Southwestern and Northwestern Oregon. The prior analysis is based on a review of existing ref3restation records and a simulation model. Optimal prior acts differ substantially from present policies. Their implementation may reduce expected costs by approximately $50 per acre. Based on ecological variables observed an 350 survival plots, prediction aids for first-year survival arid site class, the main sources of uncertainty,are established. Plant water relations, and particularly the available water capacity of soils, emerge as prime determinants of survival and productivity. During preposterior analysis, Bayes' strategy translates ecological knowledge directly into optimal managerial choices for specific site units. Site information is evaluated economically, based on prospective reduction of reforestation costs. Expected values of site information are relatively low and almost identical in both ownerships. In the Northwestern Oregon study, it is a rather uniform environment for reforestation which limits the value of information. In the very diverse environment of the Southwestern Oregon ownership, lower marginal costs for plantation establishment, and smaller opportunity losses set these limits. A larger potential value of site information is likely for activities with high marginal costs in Southwestern Oregon. Bayesian decision analysis emphasizes the duality of ecology and economics in forest management. Combined with a system of collecting and analyzing operational records, it resembles a traditional forestry approach to uncertainty: Biolley's control method. As an extended, economically, statistically and computationally refined equivalent of the control method, Bayesian decision analysis deserves a place in the theory of forestry and in practical management of our forests. Title: The valuation and use of site information for Douglas-fir reforestation in Western Oregon : a decision analysis Author: Schöne, Dieter Hans-Friedrich Existing forest site maps have been described as "invaluable tools" in forest management. Their, economic value potentially materializes as the summed advantage from better decisions in all phases of forestry. Via Bayesian decision analysis, this study establishes optimal use and economic value of site information for one facet of management only: The choice of an optimal planting density in Douglas-fir reforestation. Two case studies were undertaken in extremely different environments of Southwestern and Northwestern Oregon. The prior analysis is based on a review of existing ref3restation records and a simulation model. Optimal prior acts differ substantially from present policies. Their implementation may reduce expected costs by approximately $50 per acre. Based on ecological variables observed an 350 survival plots, prediction aids for first-year survival arid site class, the main sources of uncertainty,are established. Plant water relations, and particularly the available water capacity of soils, emerge as prime determinants of survival and productivity. During preposterior analysis, Bayes' strategy translates ecological knowledge directly into optimal managerial choices for specific site units. Site information is evaluated economically, based on prospective reduction of reforestation costs. Expected values of site information are relatively low and almost identical in both ownerships. In the Northwestern Oregon study, it is a rather uniform environment for reforestation which limits the value of information. In the very diverse environment of the Southwestern Oregon ownership, lower marginal costs for plantation establishment, and smaller opportunity losses set these limits. A larger potential value of site information is likely for activities with high marginal costs in Southwestern Oregon. Bayesian decision analysis emphasizes the duality of ecology and economics in forest management. Combined with a system of collecting and analyzing operational records, it resembles a traditional forestry approach to uncertainty: Biolley's control method. As an extended, economically, statistically and computationally refined equivalent of the control method, Bayesian decision analysis deserves a place in the theory of forestry and in practical management of our forests. Close

• 2. [Article] Physiological and anatomical studies of several groups of Douglas-fir (pseudotsuga menziesii (Mirb.) Franco) seedlings which demonstrated differential survival potential under drought stress

  Several hundred two year old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were planted in an enclosure designed to permit control of soil moisture. The seedlings came from five seed sources ...

  Citation × Citation Citation Abstract Copy Title: Physiological and anatomical studies of several groups of Douglas-fir (pseudotsuga menziesii (Mirb.) Franco) seedlings which demonstrated differential survival potential under drought stress Author: Heiner, Terry Charles, 1941- Several hundred two year old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were planted in an enclosure designed to permit control of soil moisture. The seedlings came from five seed sources in southern Oregon and one seed source in northwestern Oregon. Mortality terminal and lateral budburst, and soil moisture were recorded during the growing season. The final death count showed that the mortality of the northwest Oregon seed source (84%) differed significantly (at the 1% level) from that of four southern Oregon seed sources (ca 44%) and that the mortality of all differed significantly from that of a fifth southern Oregon source (30%). The purpose of this study was to determine what anatomical, morphological, and physiological characteristics were associated with survival. Root length, calcium-potassium ratio, cuticle thickness, shoot-root ratio, and root surface area are not correlated with mortality. A relation between mortality and the amount and rate of budburst was found. The low bud activity and high mortality of the northwest Oregon seedlings may be an expression of their physiological condition. Earlier bud activity by the southern Oregon seedlings may be a response to a lower minimum temperature, and is a survival advantage in areas with severe summer drought. Title: Physiological and anatomical studies of several groups of Douglas-fir (pseudotsuga menziesii (Mirb.) Franco) seedlings which demonstrated differential survival potential under drought stress Author: Heiner, Terry Charles, 1941- Several hundred two year old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were planted in an enclosure designed to permit control of soil moisture. The seedlings came from five seed sources in southern Oregon and one seed source in northwestern Oregon. Mortality terminal and lateral budburst, and soil moisture were recorded during the growing season. The final death count showed that the mortality of the northwest Oregon seed source (84%) differed significantly (at the 1% level) from that of four southern Oregon seed sources (ca 44%) and that the mortality of all differed significantly from that of a fifth southern Oregon source (30%). The purpose of this study was to determine what anatomical, morphological, and physiological characteristics were associated with survival. Root length, calcium-potassium ratio, cuticle thickness, shoot-root ratio, and root surface area are not correlated with mortality. A relation between mortality and the amount and rate of budburst was found. The low bud activity and high mortality of the northwest Oregon seedlings may be an expression of their physiological condition. Earlier bud activity by the southern Oregon seedlings may be a response to a lower minimum temperature, and is a survival advantage in areas with severe summer drought. Close

• 3. [Article] Soil and growth studies in Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] stands near Molalla, Oregon

  In 1957 three Douglas-fir stands (15-, 25-, and 40-year-old age classes) were selected on a tree farm in the Cascade foothills of northwestern Oregon to study factors affecting site productivity. Soil-moisture, ...

  Citation × Citation Citation Abstract Copy Title: Soil and growth studies in Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] stands near Molalla, Oregon Author: Strand, Robert Fenton In 1957 three Douglas-fir stands (15-, 25-, and 40-year-old age classes) were selected on a tree farm in the Cascade foothills of northwestern Oregon to study factors affecting site productivity. Soil-moisture, soil-temperature and seasonal radial- growth pattern measurements were made with a Colman moisture meter and a dial gauge dendrometer on thinned and unthinned subareas. Soil temperatures were significantly increased by thinning in each stand. This effect decreased with soil depth and increased with increasing intensity of thinning. Root distribution studies eight years after thinning showed that a heavily thinned stand had relatively few roots in the lower profile between the remaining trees, in contrast to the complete distribution throughout the profile in the unthinned subareas. This would indicate less overall soil-moisture depletion with thinning since the available soil-moisture levels measured within the fully rooted zone were not significantly different for the various thinning treatments. As expected radial growth increased significantly with increasing intensity of thinning. The amount and proportion of late season growth tended to increase with increasing thinning intensity although the observed differences were not statistically significant. Late season growth, however, was significantly increased by increasing crown position (intermediate to dominant) regardless of thinning treatment. Irrigation of selected trees at a ridgetop area extended the spring maximum radial growth rate throughout most of the summer. On comparable non-irrigated trees growth retardation was detectable in the range of one-half to one atmospheres of soil-moisture tension. Growth cessation occurred when soil-moisture-tension values reached the two to five atmosphere range. Irrigation of trees in a young hillside bench stand slightly increased radial growth rate during the first two years, but decreased growth in relation to non-irrigated trees during the next two years apparently as a result of excess irrigation. Fertilization with high rates of nitrogen and phosphorus fertilizers increased the late season radial growth of irrigated and non-irrigated trees in both stands. The late season response is attributed to a dwindling supply of mineralized soil nitrogen in the late summer and early fall. Irrigation and fertilization combined gave approximately additive increases in radial growth which ranged from 35 to 60 percent. It is hypothesized that potential radial growth (except for short periods at the start and end of the growing season) is equivalent to the maximum spring rate. Departures from this maximum result from deficiencies in moisture, mineral nutrient elements, or heat. Thus the maximum growth rate is proposed as an important characteristic, reflecting the potential carbohydrate productive capacity of the crown when raw material levels exceed rate limiting supplies. The fertility status of each research area was assessed by various means including soil chemical and physical analyses, sampling and chemical analyses of forest floor and litter fall material and pot fertility tests. The relative ranking of these areas in terms of fertility was consistent with their site index or productivity rating. Monterey pine and Douglas-fir seedling test plants grown on the potted soils from the different horizons in each profile responded to nitrogen, phosphorus, and sulphur additions. In field tests nitrogen fertilization stimulated radial growth of Douglas-fir whereas phosphorus fertilizer at high application rates resulted in a growth depression. Title: Soil and growth studies in Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] stands near Molalla, Oregon Author: Strand, Robert Fenton In 1957 three Douglas-fir stands (15-, 25-, and 40-year-old age classes) were selected on a tree farm in the Cascade foothills of northwestern Oregon to study factors affecting site productivity. Soil-moisture, soil-temperature and seasonal radial- growth pattern measurements were made with a Colman moisture meter and a dial gauge dendrometer on thinned and unthinned subareas. Soil temperatures were significantly increased by thinning in each stand. This effect decreased with soil depth and increased with increasing intensity of thinning. Root distribution studies eight years after thinning showed that a heavily thinned stand had relatively few roots in the lower profile between the remaining trees, in contrast to the complete distribution throughout the profile in the unthinned subareas. This would indicate less overall soil-moisture depletion with thinning since the available soil-moisture levels measured within the fully rooted zone were not significantly different for the various thinning treatments. As expected radial growth increased significantly with increasing intensity of thinning. The amount and proportion of late season growth tended to increase with increasing thinning intensity although the observed differences were not statistically significant. Late season growth, however, was significantly increased by increasing crown position (intermediate to dominant) regardless of thinning treatment. Irrigation of selected trees at a ridgetop area extended the spring maximum radial growth rate throughout most of the summer. On comparable non-irrigated trees growth retardation was detectable in the range of one-half to one atmospheres of soil-moisture tension. Growth cessation occurred when soil-moisture-tension values reached the two to five atmosphere range. Irrigation of trees in a young hillside bench stand slightly increased radial growth rate during the first two years, but decreased growth in relation to non-irrigated trees during the next two years apparently as a result of excess irrigation. Fertilization with high rates of nitrogen and phosphorus fertilizers increased the late season radial growth of irrigated and non-irrigated trees in both stands. The late season response is attributed to a dwindling supply of mineralized soil nitrogen in the late summer and early fall. Irrigation and fertilization combined gave approximately additive increases in radial growth which ranged from 35 to 60 percent. It is hypothesized that potential radial growth (except for short periods at the start and end of the growing season) is equivalent to the maximum spring rate. Departures from this maximum result from deficiencies in moisture, mineral nutrient elements, or heat. Thus the maximum growth rate is proposed as an important characteristic, reflecting the potential carbohydrate productive capacity of the crown when raw material levels exceed rate limiting supplies. The fertility status of each research area was assessed by various means including soil chemical and physical analyses, sampling and chemical analyses of forest floor and litter fall material and pot fertility tests. The relative ranking of these areas in terms of fertility was consistent with their site index or productivity rating. Monterey pine and Douglas-fir seedling test plants grown on the potted soils from the different horizons in each profile responded to nitrogen, phosphorus, and sulphur additions. In field tests nitrogen fertilization stimulated radial growth of Douglas-fir whereas phosphorus fertilizer at high application rates resulted in a growth depression. Close

• 4. [Article] Habitat relationships of birds and young-growth Douglas-fir in northwestern California

  Ninety-one species of birds were surveyed in grass/forb, early and late shrub/sapling, pole, and medium sawtimber stages of young-growth Douglas-fir in northwestern California; patterns of bird distribution ...

  Citation × Citation Citation Abstract Copy Title: Habitat relationships of birds and young-growth Douglas-fir in northwestern California Author: Marcot, Bruce G. Ninety-one species of birds were surveyed in grass/forb, early and late shrub/sapling, pole, and medium sawtimber stages of young-growth Douglas-fir in northwestern California; patterns of bird distribution and abundance were related to habitat conditions and even-age silvicultural treatments. Seven species (band-tailed pigeon, western wood pewee, dusky flycatcher, western bluebird, fox sparrow, purple finch, and evening grosbeak) have probably increased in population size or distribution since extensive clearcutting in the study area began in the early 1950's. Six species (Hammond's flycatcher, chestnut-backed chickadee, red-breasted nuthatch, brown creeper, golden-crowned kinglet, and hermit warbler) are restricted to forest stages and probably have decreased in population size or distribution. Abundances of various species were associated with presence of a forest overstory, hardwood stem density, deciduous foliage volume, height and patchiness of shrub cover, number plant species, and snag density. Slope angle and distance to permanent water or to the next nearest similar habitat type explained some variation in abundance of a few species. The grass/forb stage had the lowest number of bird species and lowest total density, while the late shrub/sapling stage had the highest; species composition varied markedly across the young-growth stages. Cluster analysis defined Shrub stage specialists and forest stage Specialists. Seasonal patterns of permanent resident species suggested that the shrub stage specialists are most limited in distribution during winter, and that their winter distributions may reflect optimal ("source") habitat. In contrast, forest stage specialists showed no seasonal changes of distribution, or were more restricted in distribution during the breeding season. All phases of the clearcutting system, including site preparation, stocking control, intermediate treatments, and final harvest, greatly affect stand conditions. No one stand condition, young-growth stage, or silvicultural treatment provided best habitat for all bird species. Simplification of forest stand structure by reduction or elimination of hardwoods, snags, and large diameter softwoods, could lead to low within-stand but high between-stand diversity of vegetation and bird assemblages. Even-age silvicultural systems, however, can integrate management objectives for timber production and bird habitat. Title: Habitat relationships of birds and young-growth Douglas-fir in northwestern California Author: Marcot, Bruce G. Ninety-one species of birds were surveyed in grass/forb, early and late shrub/sapling, pole, and medium sawtimber stages of young-growth Douglas-fir in northwestern California; patterns of bird distribution and abundance were related to habitat conditions and even-age silvicultural treatments. Seven species (band-tailed pigeon, western wood pewee, dusky flycatcher, western bluebird, fox sparrow, purple finch, and evening grosbeak) have probably increased in population size or distribution since extensive clearcutting in the study area began in the early 1950's. Six species (Hammond's flycatcher, chestnut-backed chickadee, red-breasted nuthatch, brown creeper, golden-crowned kinglet, and hermit warbler) are restricted to forest stages and probably have decreased in population size or distribution. Abundances of various species were associated with presence of a forest overstory, hardwood stem density, deciduous foliage volume, height and patchiness of shrub cover, number plant species, and snag density. Slope angle and distance to permanent water or to the next nearest similar habitat type explained some variation in abundance of a few species. The grass/forb stage had the lowest number of bird species and lowest total density, while the late shrub/sapling stage had the highest; species composition varied markedly across the young-growth stages. Cluster analysis defined Shrub stage specialists and forest stage Specialists. Seasonal patterns of permanent resident species suggested that the shrub stage specialists are most limited in distribution during winter, and that their winter distributions may reflect optimal ("source") habitat. In contrast, forest stage specialists showed no seasonal changes of distribution, or were more restricted in distribution during the breeding season. All phases of the clearcutting system, including site preparation, stocking control, intermediate treatments, and final harvest, greatly affect stand conditions. No one stand condition, young-growth stage, or silvicultural treatment provided best habitat for all bird species. Simplification of forest stand structure by reduction or elimination of hardwoods, snags, and large diameter softwoods, could lead to low within-stand but high between-stand diversity of vegetation and bird assemblages. Even-age silvicultural systems, however, can integrate management objectives for timber production and bird habitat. Close