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• 1. [Article] A quantitative analysis of log volume concepts and product derivatives

  One of the most important challenges facing foresters is the development of a raw material measurement system designed to give a complete inventory of log volume and to assist in planning the complete management ...

  Citation × Citation Citation Abstract Copy Title: A quantitative analysis of log volume concepts and product derivatives Author: Smith, Douglas Sterling One of the most important challenges facing foresters is the development of a raw material measurement system designed to give a complete inventory of log volume and to assist in planning the complete management of log production. This paper introduces a concept of production analysis in terms of solid fiber content. The basis for the development of this concept is the measurement of logs and log production in terms of cubic feet. Total raw material accountability is maintained throughout the manufacturing process. A mill study was undertaken to compare the results of this type of analysis with results obtained by traditional analytical methods. It was found that raw material management by this analysis can be useful in measuring the effectiveness of a production design. This analysis has further usefulness in projecting the results of proposed changes in production design. The mill study was undertaken with the log input, primary lumber products, and sawmill residuals measured in terms of cubic feet of wood fiber. This study is referred to as treatment A in this paper. The mill study data were used to project two changes in sawing practices, treatments B and C, and the expected results are presented. The 471 logs in the study had a volume of 172,850 board feet gross, and 143,490 board feet net, Scribner scale. The logs had a volume of 24, 574 cubic feet on the basis of Smalian's cubic foot rule. The volumes in the study were assigned dollar values on the basis of grade and projected on the basis of an annual cut of 30 million board feet, assuming the same variables encountered in the test material. By using the values assigned to the products in Treatment A, the total value of products was $2,802,481, based on the assumed 30 million board feet cutting schedule. The yearly product value for Treatment B was $175,769 more than Treatment A, and the yearly product value for Treatment C was $302,632 more than Treatment A. It is emphasized that any comparison of other situations with those defined in this paper must be carefully qualified. A review of present and past log measurement systems includes a discussion of the British Hoppus Foot, and the shaku and koku units of measure used in Japan. Various cubic foot rules discussed include Newton's formula, Huber, Smalian, Rapraeger and Sorensen. The more common board foot rules include Scribner, Scribner Decimal C, Spaulding, British Columbia rule, International 1/4-inch and 1/8-inch rules, Brereton, and Doyle log rules. Measurement by displacement and weight is discussed. Efforts in comparing the economics of different measurement methods are reported. The development of log residual products during manufacture is discussed. These present both problems in terms of disposal and opportunities for additional economic development. A concerted effort is needed to design mensurational techniques that will act as incentives toward the most complete and profitable utilization of our forest resource. Toward this end it is suggested that those in the field of forest mensuration coordinate their efforts with the research and utilization fields toward a complete understanding of the complex problem of wood measurement. This paper concludes that cubic analysis of log input and production outflow can better serve the needs of the forest products industry. Title: A quantitative analysis of log volume concepts and product derivatives Author: Smith, Douglas Sterling One of the most important challenges facing foresters is the development of a raw material measurement system designed to give a complete inventory of log volume and to assist in planning the complete management of log production. This paper introduces a concept of production analysis in terms of solid fiber content. The basis for the development of this concept is the measurement of logs and log production in terms of cubic feet. Total raw material accountability is maintained throughout the manufacturing process. A mill study was undertaken to compare the results of this type of analysis with results obtained by traditional analytical methods. It was found that raw material management by this analysis can be useful in measuring the effectiveness of a production design. This analysis has further usefulness in projecting the results of proposed changes in production design. The mill study was undertaken with the log input, primary lumber products, and sawmill residuals measured in terms of cubic feet of wood fiber. This study is referred to as treatment A in this paper. The mill study data were used to project two changes in sawing practices, treatments B and C, and the expected results are presented. The 471 logs in the study had a volume of 172,850 board feet gross, and 143,490 board feet net, Scribner scale. The logs had a volume of 24, 574 cubic feet on the basis of Smalian's cubic foot rule. The volumes in the study were assigned dollar values on the basis of grade and projected on the basis of an annual cut of 30 million board feet, assuming the same variables encountered in the test material. By using the values assigned to the products in Treatment A, the total value of products was $2,802,481, based on the assumed 30 million board feet cutting schedule. The yearly product value for Treatment B was $175,769 more than Treatment A, and the yearly product value for Treatment C was $302,632 more than Treatment A. It is emphasized that any comparison of other situations with those defined in this paper must be carefully qualified. A review of present and past log measurement systems includes a discussion of the British Hoppus Foot, and the shaku and koku units of measure used in Japan. Various cubic foot rules discussed include Newton's formula, Huber, Smalian, Rapraeger and Sorensen. The more common board foot rules include Scribner, Scribner Decimal C, Spaulding, British Columbia rule, International 1/4-inch and 1/8-inch rules, Brereton, and Doyle log rules. Measurement by displacement and weight is discussed. Efforts in comparing the economics of different measurement methods are reported. The development of log residual products during manufacture is discussed. These present both problems in terms of disposal and opportunities for additional economic development. A concerted effort is needed to design mensurational techniques that will act as incentives toward the most complete and profitable utilization of our forest resource. Toward this end it is suggested that those in the field of forest mensuration coordinate their efforts with the research and utilization fields toward a complete understanding of the complex problem of wood measurement. This paper concludes that cubic analysis of log input and production outflow can better serve the needs of the forest products industry. Close

• 2. [Article] A preliminary investigation into the use of the tarif system and three tree selection methods for obtaining Douglas-fir stand and stock tables from large-scale aerial photography

  As a preliminary step toward the establishment of a 70 mm. aerial photo timber inventory system capable of generating accurate stand tables, stock tables, and gross volume estimates, this project focuses ...

  Citation × Citation Citation Abstract Copy Title: A preliminary investigation into the use of the tarif system and three tree selection methods for obtaining Douglas-fir stand and stock tables from large-scale aerial photography Author: McCadden, Richard Jay As a preliminary step toward the establishment of a 70 mm. aerial photo timber inventory system capable of generating accurate stand tables, stock tables, and gross volume estimates, this project focuses on the development of a system which (1) eliminates the need to measure tree height on the photos through use of the tarif system and, (2) incorporates the use of three distinct tree selection methods-- fixed plot, variable plot, and line transect sampling. The methodology is developed and applied to a 346 acre parcel of Douglas-fir forestland. The accuracy of individual tree predictions for diameter at breast height, volume, tarif number, and tree height (which is derived without traditional photo measurement) are evaluated by ground subsampling a 206- tree validation set and comparing actual and predicted values. The results show that an average underprediction of ground-measured tarif number by about 5% occurs, which in turn results in similar underpredictions of tree volume and height. The accuracy of the stand tables, stock tables, and gross volume estimates are examined by comparison to independently derived ground measurements. The photo estimates of mean gross volume per acre, using each of the three photo tree selection methods, are all within 5% of the ground-derived estimates; in all cases the 68% confidence intervals of the ground and photo estimates overlap. Graphic comparisons of the photo and ground-derived stand and stock tables are presented; they are similar, except for the inability of the photo method to accurately predict the stocking of trees less than twelve inches in stem diameter. The aerial photo system, using each of the three tree selection methods, demonstrates an ability to produce results comparable to those derived from conventional ground inventory techniques. Future research is recommended, and specific needs for this research are identified. Title: A preliminary investigation into the use of the tarif system and three tree selection methods for obtaining Douglas-fir stand and stock tables from large-scale aerial photography Author: McCadden, Richard Jay As a preliminary step toward the establishment of a 70 mm. aerial photo timber inventory system capable of generating accurate stand tables, stock tables, and gross volume estimates, this project focuses on the development of a system which (1) eliminates the need to measure tree height on the photos through use of the tarif system and, (2) incorporates the use of three distinct tree selection methods-- fixed plot, variable plot, and line transect sampling. The methodology is developed and applied to a 346 acre parcel of Douglas-fir forestland. The accuracy of individual tree predictions for diameter at breast height, volume, tarif number, and tree height (which is derived without traditional photo measurement) are evaluated by ground subsampling a 206- tree validation set and comparing actual and predicted values. The results show that an average underprediction of ground-measured tarif number by about 5% occurs, which in turn results in similar underpredictions of tree volume and height. The accuracy of the stand tables, stock tables, and gross volume estimates are examined by comparison to independently derived ground measurements. The photo estimates of mean gross volume per acre, using each of the three photo tree selection methods, are all within 5% of the ground-derived estimates; in all cases the 68% confidence intervals of the ground and photo estimates overlap. Graphic comparisons of the photo and ground-derived stand and stock tables are presented; they are similar, except for the inability of the photo method to accurately predict the stocking of trees less than twelve inches in stem diameter. The aerial photo system, using each of the three tree selection methods, demonstrates an ability to produce results comparable to those derived from conventional ground inventory techniques. Future research is recommended, and specific needs for this research are identified. Close

• 3. [Article] A key to the literature presenting tree volume and taper equations for species in the Pacific Northwest and California

  Summaries from 49 published articles on tree volume and taper equations are presented for 39 tree species found in California, Oregon, Washington, British Columbia, southeast Alaska, Idaho, and western ...

  Citation × Citation Citation Abstract Copy Title: A key to the literature presenting tree volume and taper equations for species in the Pacific Northwest and California Author: Oregon State University. Forest Research Laboratory, Hann, David W. Summaries from 49 published articles on tree volume and taper equations are presented for 39 tree species found in California, Oregon, Washington, British Columbia, southeast Alaska, Idaho, and western Montana. The summaries are organized by species and then by type of equation (volume or taper). Each summary describes the types of dependent variables predicted by the equations and the geographic location, number of trees, range in DBH, and range in total height for trees in the sample used to develop the equations. Title: A key to the literature presenting tree volume and taper equations for species in the Pacific Northwest and California Author: Oregon State University. Forest Research Laboratory, Hann, David W. Summaries from 49 published articles on tree volume and taper equations are presented for 39 tree species found in California, Oregon, Washington, British Columbia, southeast Alaska, Idaho, and western Montana. The summaries are organized by species and then by type of equation (volume or taper). Each summary describes the types of dependent variables predicted by the equations and the geographic location, number of trees, range in DBH, and range in total height for trees in the sample used to develop the equations. Close

• 4. [Article] Equations for predicting the largest crown width of stand-grown trees in western Oregon

  Largest crown width (LCW) equations for stand-grown trees were developed for 14 tree species found in western Oregon. The equations are used in the growth-and-yield model ORGANON and in the stand-visualization ...

  Citation × Citation Citation Abstract Copy Title: Equations for predicting the largest crown width of stand-grown trees in western Oregon Author: Oregon State University. Forest Research Laboratory, Hann, David W. Largest crown width (LCW) equations for stand-grown trees were developed for 14 tree species found in western Oregon. The equations are used in the growth-and-yield model ORGANON and in the stand-visualization program VIZ4ST. They were constructed such that LCW equals the maximum crown width of open-grown trees when the crown ratio is equal to one. Tree measurements needed for the equations are diameter at breast height (in.), total tree height (ft), and crown length (ft). Title: Equations for predicting the largest crown width of stand-grown trees in western Oregon Author: Oregon State University. Forest Research Laboratory, Hann, David W. Largest crown width (LCW) equations for stand-grown trees were developed for 14 tree species found in western Oregon. The equations are used in the growth-and-yield model ORGANON and in the stand-visualization program VIZ4ST. They were constructed such that LCW equals the maximum crown width of open-grown trees when the crown ratio is equal to one. Tree measurements needed for the equations are diameter at breast height (in.), total tree height (ft), and crown length (ft). Close

• 5. [Article] A key to the literature presenting site-index and dominant-height-growth curves and equations for species in the Pacific Northwest and California

  Summaries from 49 published articles on site-index and dominant-heightgrowth curves and equations are presented for 20 tree species or species groups found in California, Oregon, Washington, British Columbia, ...

  Citation × Citation Citation Abstract Copy Title: A key to the literature presenting site-index and dominant-height-growth curves and equations for species in the Pacific Northwest and California Author: Oregon State University. Forest Research Laboratory, Hann, David W. Summaries from 49 published articles on site-index and dominant-heightgrowth curves and equations are presented for 20 tree species or species groups found in California, Oregon, Washington, British Columbia, southeastern Alaska, Idaho, and western Montana. The summaries are organized by species. Each summary describes the modeling approach, type of curves/ equations, base age, and type of age presented in the article. In addition, the geographic location, number of trees or plots, range in age, and range in site index used to develop the curves/equations are also described. Title: A key to the literature presenting site-index and dominant-height-growth curves and equations for species in the Pacific Northwest and California Author: Oregon State University. Forest Research Laboratory, Hann, David W. Summaries from 49 published articles on site-index and dominant-heightgrowth curves and equations are presented for 20 tree species or species groups found in California, Oregon, Washington, British Columbia, southeastern Alaska, Idaho, and western Montana. The summaries are organized by species. Each summary describes the modeling approach, type of curves/ equations, base age, and type of age presented in the article. In addition, the geographic location, number of trees or plots, range in age, and range in site index used to develop the curves/equations are also described. Close

• 6. [Article] Equations for predicting the height to crown base of six tree species in the central western Willamette Valley of Oregon

  This paper presents equations developed to predict the height to live crown base of six species in the central western Willamette Valley of Oregon. Weighted nonlinear regression was used to fit a separate ...

  Citation × Citation Citation Abstract Copy Title: Equations for predicting the height to crown base of six tree species in the central western Willamette Valley of Oregon Author: Zumrawi, Abdel Azim M. A., Oregon State University. Forest Research Laboratory, Hann, David W. This paper presents equations developed to predict the height to live crown base of six species in the central western Willamette Valley of Oregon. Weighted nonlinear regression was used to fit a separate logistic equation for each species. The predictor variables are total tree height, crown competition factor in trees with larger diameter at breast height than the subject tree, stand basal area, and diameter-height ratio. The equations will be used in two ways: 1) to estimate crown ratio on trees for which that measurement is missing, and 2) to simulate crown change in a single-tree/distance-independent growth and yield model. Application of these equations will be most reliable in stands that are free from thinning effect. Title: Equations for predicting the height to crown base of six tree species in the central western Willamette Valley of Oregon Author: Zumrawi, Abdel Azim M. A., Oregon State University. Forest Research Laboratory, Hann, David W. This paper presents equations developed to predict the height to live crown base of six species in the central western Willamette Valley of Oregon. Weighted nonlinear regression was used to fit a separate logistic equation for each species. The predictor variables are total tree height, crown competition factor in trees with larger diameter at breast height than the subject tree, stand basal area, and diameter-height ratio. The equations will be used in two ways: 1) to estimate crown ratio on trees for which that measurement is missing, and 2) to simulate crown change in a single-tree/distance-independent growth and yield model. Application of these equations will be most reliable in stands that are free from thinning effect. Close

• 7. [Article] Calculation of tree volume and surface area by the height-accumulation method

  This study was initiated to determine the accuracy and limits of the height-accumulation method of measuring tree volume and surface area for Pacific Northwest second-growth trees. Thirty trees were selected ...

  Citation × Citation Citation Abstract Copy Title: Calculation of tree volume and surface area by the height-accumulation method Author: Arney, James Douglas, 1941- This study was initiated to determine the accuracy and limits of the height-accumulation method of measuring tree volume and surface area for Pacific Northwest second-growth trees. Thirty trees were selected from various thinning treatments in a 55 year old Douglas-fir forest. Each tree was measured with the highly accurate Barr and Stroud optical dendrometer and height, surface area, and cubic-foot volume were calculated on a Control Data Corporation 3300 electronic computer. A Spiegel-Relaskop was used to measure taper steps for height-accumulation. These results were then compared with the dendrometer results to determine the accuracy of this technique. The Relaskop was found to be inadequate when used alone, but when a 4-power telescope was mounted, it greatly enhanced the usefulness of the instrument. The telescopic Spiegel-Relaskop, using the height-accumulation method, was found to be capable of measuring volume with comparable accuracy to the optical dendrometer. The study revealed that volumes determined using height-accumulation, measured with a telescopic Spiegel-Relaskop, in conjunction with point sampling should estimate volume of a stand as accurately as any other cruising technique. In addition this method, like other recently developed methods, eliminates the use of volume tables and their inherent biases. Title: Calculation of tree volume and surface area by the height-accumulation method Author: Arney, James Douglas, 1941- This study was initiated to determine the accuracy and limits of the height-accumulation method of measuring tree volume and surface area for Pacific Northwest second-growth trees. Thirty trees were selected from various thinning treatments in a 55 year old Douglas-fir forest. Each tree was measured with the highly accurate Barr and Stroud optical dendrometer and height, surface area, and cubic-foot volume were calculated on a Control Data Corporation 3300 electronic computer. A Spiegel-Relaskop was used to measure taper steps for height-accumulation. These results were then compared with the dendrometer results to determine the accuracy of this technique. The Relaskop was found to be inadequate when used alone, but when a 4-power telescope was mounted, it greatly enhanced the usefulness of the instrument. The telescopic Spiegel-Relaskop, using the height-accumulation method, was found to be capable of measuring volume with comparable accuracy to the optical dendrometer. The study revealed that volumes determined using height-accumulation, measured with a telescopic Spiegel-Relaskop, in conjunction with point sampling should estimate volume of a stand as accurately as any other cruising technique. In addition this method, like other recently developed methods, eliminates the use of volume tables and their inherent biases. Close