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• 1. [Article] Predicting merchantable volume in cubic feet to a variable top and in Scribner board feet to a 6-inch top for six major conifers of southwest Oregon

  Citation × Citation Citation Abstract Copy Title: Predicting merchantable volume in cubic feet to a variable top and in Scribner board feet to a 6-inch top for six major conifers of southwest Oregon Author: Oregon State University. Forest Research Laboratory, Hann, David W., Walters, David K. Title: Predicting merchantable volume in cubic feet to a variable top and in Scribner board feet to a 6-inch top for six major conifers of southwest Oregon Author: Oregon State University. Forest Research Laboratory, Hann, David W., Walters, David K. Close

• 2. [Article] Equations for predicting basal area increment in Douglas-fir and grand fir

  Citation × Citation Citation Abstract Copy Title: Equations for predicting basal area increment in Douglas-fir and grand fir Author: Ritchie, Martin W., Oregon State University. Forest Research Laboratory, Hann, David W. Title: Equations for predicting basal area increment in Douglas-fir and grand fir Author: Ritchie, Martin W., Oregon State University. Forest Research Laboratory, Hann, David W. Close

• 3. [Article] Taper equations for six conifer species in southwest Oregon

  Citation × Citation Citation Abstract Copy Title: Taper equations for six conifer species in southwest Oregon Author: Oregon State University. Forest Research Laboratory, Hann, David W., Walters, David K. Title: Taper equations for six conifer species in southwest Oregon Author: Oregon State University. Forest Research Laboratory, Hann, David W., Walters, David K. Close

• 4. [Article] Maximum crown-width equations for southwestern Oregon tree species

  Citation × Citation Citation Abstract Copy Title: Maximum crown-width equations for southwestern Oregon tree species Author: Oregon State University. Forest Research Laboratory, Paine, David P., Hann, David W. Title: Maximum crown-width equations for southwestern Oregon tree species Author: Oregon State University. Forest Research Laboratory, Paine, David P., Hann, David W. Close

• 5. [Article] Diameter growth equations for fourteen tree species in Southwest Oregon

  Equations are presented that predict individual-tree 5-year diameter growth, outside bark, for 14 tree species in southwest Oregon. The data used to develop the equations came from 19,245 trees sampled ...

  Citation × Citation Citation Abstract Copy Title: Diameter growth equations for fourteen tree species in Southwest Oregon Author: Larsen, David R., Oregon State University. Forest Research Laboratory, Hann, David W. Equations are presented that predict individual-tree 5-year diameter growth, outside bark, for 14 tree species in southwest Oregon. The data used to develop the equations came from 19,245 trees sampled from 391 stands in the study area. These equations express diameter growth as a function of diameter at breast height, crown ratio, site index, total stand basal area, and stand basal area in trees with diameters larger than the subject tree's diameter. The parameters of the equations were estimated by using weighted, nonlinear regression. Title: Diameter growth equations for fourteen tree species in Southwest Oregon Author: Larsen, David R., Oregon State University. Forest Research Laboratory, Hann, David W. Equations are presented that predict individual-tree 5-year diameter growth, outside bark, for 14 tree species in southwest Oregon. The data used to develop the equations came from 19,245 trees sampled from 391 stands in the study area. These equations express diameter growth as a function of diameter at breast height, crown ratio, site index, total stand basal area, and stand basal area in trees with diameters larger than the subject tree's diameter. The parameters of the equations were estimated by using weighted, nonlinear regression. Close

• 6. [Article] Predicting height for undamaged and damaged trees in southwest Oregon

  Equations for predicting tree height as a function of diameter outside bark at breast height are presented for various tree species common to southwest Oregon. Data for damaged and undamaged trees were ...

  Citation × Citation Citation Abstract Copy Title: Predicting height for undamaged and damaged trees in southwest Oregon Author: Hanus, Mark L., Oregon State University. Forest Research Laboratory, Hann, David W., Marshall, David D. Equations for predicting tree height as a function of diameter outside bark at breast height are presented for various tree species common to southwest Oregon. Data for damaged and undamaged trees were analyzed with weighted nonlinear regression techniques. The effects of specific damaging agents and their severity on the height-diameter relationship were explored. Damage correction multipliers were estimated, then used to correct predicted height where damage was noted. Because the relationship between height and diameter changes with the competitive position of the tree in a stand, alternative equations are presented that include the average height and diameter of the 40 largest-diameter undamaged conifer trees per acre. Foresters can use these "height-diameter" equations to reduce the time-consuming task of measuring heights of every tree in an inventory, stand exam, or timber cruise. They can also use these equations to estimate the change in height as diameter changes. These equations will be incorporated into the new southwest Oregon version of ORGANON, which extends the model to older stands and stands with a heavier component of hardwood species. Title: Predicting height for undamaged and damaged trees in southwest Oregon Author: Hanus, Mark L., Oregon State University. Forest Research Laboratory, Hann, David W., Marshall, David D. Equations for predicting tree height as a function of diameter outside bark at breast height are presented for various tree species common to southwest Oregon. Data for damaged and undamaged trees were analyzed with weighted nonlinear regression techniques. The effects of specific damaging agents and their severity on the height-diameter relationship were explored. Damage correction multipliers were estimated, then used to correct predicted height where damage was noted. Because the relationship between height and diameter changes with the competitive position of the tree in a stand, alternative equations are presented that include the average height and diameter of the 40 largest-diameter undamaged conifer trees per acre. Foresters can use these "height-diameter" equations to reduce the time-consuming task of measuring heights of every tree in an inventory, stand exam, or timber cruise. They can also use these equations to estimate the change in height as diameter changes. These equations will be incorporated into the new southwest Oregon version of ORGANON, which extends the model to older stands and stands with a heavier component of hardwood species. Close

• 7. [Article] Extending southwest Oregon's Douglas-fir dominant height growth equation to older ages

  Hann and Scrivani (1987) developed dominant height growth equations for Douglas- fir in southwest Oregon using stem analysis data sets with an upper age of approximately 125 years at breast height. The ...

  Citation × Citation Citation Abstract Copy Title: Extending southwest Oregon's Douglas-fir dominant height growth equation to older ages Author: Oregon State University. Forest Research Laboratory, Hann, David W. Hann and Scrivani (1987) developed dominant height growth equations for Douglas- fir in southwest Oregon using stem analysis data sets with an upper age of approximately 125 years at breast height. The objective of this study was to determine whether these equations could be extrapolated for ages of 250 years or more. Data for the evaluation came from stem analysis of 60 dominant trees located in 30 "older" stands. Intensive data screening indicated that 53 of these trees exhibited signs of reduced height growth during their first 100 years of development due to competition from non-tree vegetation, hardwood tree species, and possibly other conifers in non-even-aged stands. Analysis of the remaining seven site-quality trees indicated that the existing dominant height growth equation for Douglas-fir could be extrapolated to breast height ages of up to 245 years without loss of accuracy or precision. Title: Extending southwest Oregon's Douglas-fir dominant height growth equation to older ages Author: Oregon State University. Forest Research Laboratory, Hann, David W. Hann and Scrivani (1987) developed dominant height growth equations for Douglas- fir in southwest Oregon using stem analysis data sets with an upper age of approximately 125 years at breast height. The objective of this study was to determine whether these equations could be extrapolated for ages of 250 years or more. Data for the evaluation came from stem analysis of 60 dominant trees located in 30 "older" stands. Intensive data screening indicated that 53 of these trees exhibited signs of reduced height growth during their first 100 years of development due to competition from non-tree vegetation, hardwood tree species, and possibly other conifers in non-even-aged stands. Analysis of the remaining seven site-quality trees indicated that the existing dominant height growth equation for Douglas-fir could be extrapolated to breast height ages of up to 245 years without loss of accuracy or precision. Close

• 8. [Article] Enhanced height-growth-rate equations for undamaged and damaged trees in southwest Oregon

  Equations for predicting the 5-yr height growth rate of a tree are presented for six conifer species from southwest Oregon. Equations for the combination of undamaged and damaged trees were estimated with ...

  Citation × Citation Citation Abstract Copy Title: Enhanced height-growth-rate equations for undamaged and damaged trees in southwest Oregon Author: Hanus, Mark L., Oregon State University. Forest Research Laboratory, Hann, David W. Equations for predicting the 5-yr height growth rate of a tree are presented for six conifer species from southwest Oregon. Equations for the combination of undamaged and damaged trees were estimated with weighted nonlinear regression techniques. These equations are being incorporated into the new southwest Oregon version of ORGANON, a model for predicting the development of stands. The equations extend the previous model to older stands and to stands with a heavier component of hardwood tree species. The effects of specific damaging agents on the 5-yr height growth rate were explored for Douglas-fir, the most frequently encountered species, and damage correction factors were estimated. The findings of this analysis indicated that damaging agents can have a significant impact upon 5-yr height growth rate, and as a result, they can lead, over time, to diversification in within-stand structure. Therefore, a full characterization of stand development should include the prediction of the presence and frequency of the various damaging agents affecting trees within the stand and their subsequent impact upon tree attributes such as total height, height to crown base, diameter growth rate, height growth rate, and mortality rate. Title: Enhanced height-growth-rate equations for undamaged and damaged trees in southwest Oregon Author: Hanus, Mark L., Oregon State University. Forest Research Laboratory, Hann, David W. Equations for predicting the 5-yr height growth rate of a tree are presented for six conifer species from southwest Oregon. Equations for the combination of undamaged and damaged trees were estimated with weighted nonlinear regression techniques. These equations are being incorporated into the new southwest Oregon version of ORGANON, a model for predicting the development of stands. The equations extend the previous model to older stands and to stands with a heavier component of hardwood tree species. The effects of specific damaging agents on the 5-yr height growth rate were explored for Douglas-fir, the most frequently encountered species, and damage correction factors were estimated. The findings of this analysis indicated that damaging agents can have a significant impact upon 5-yr height growth rate, and as a result, they can lead, over time, to diversification in within-stand structure. Therefore, a full characterization of stand development should include the prediction of the presence and frequency of the various damaging agents affecting trees within the stand and their subsequent impact upon tree attributes such as total height, height to crown base, diameter growth rate, height growth rate, and mortality rate. Close

• 9. [Article] Equations and tables predicting gross total stem volumes in cubic feet for six major conifers of southwest Oregon

  Equations and tables predicting gross total stem volumes in cubic feet are presented for Douglas-fir, grand fir, white fir, ponderosa pine, sugar pine, and incense-cedar. The data were gathered in second-growth, ...

  Citation × Citation Citation Abstract Copy Title: Equations and tables predicting gross total stem volumes in cubic feet for six major conifers of southwest Oregon Author: Clyde, Merlise A., Oregon State University. Forest Research Laboratory, Walters, David K., Hann, David W. Equations and tables predicting gross total stem volumes in cubic feet are presented for Douglas-fir, grand fir, white fir, ponderosa pine, sugar pine, and incense-cedar. The data were gathered in second-growth, mixed-conifer stands of southwest Oregon. The basic equations use diameter outside bark at breast height and total tree height as independent variables. Tables and additional equations were developed that incorporate crown ratio for Douglas-fir, grand fir, and white fir. Equations that predict stump diameter, volume below breast height, and volume above breast height also are developed and presented for each species. Title: Equations and tables predicting gross total stem volumes in cubic feet for six major conifers of southwest Oregon Author: Clyde, Merlise A., Oregon State University. Forest Research Laboratory, Walters, David K., Hann, David W. Equations and tables predicting gross total stem volumes in cubic feet are presented for Douglas-fir, grand fir, white fir, ponderosa pine, sugar pine, and incense-cedar. The data were gathered in second-growth, mixed-conifer stands of southwest Oregon. The basic equations use diameter outside bark at breast height and total tree height as independent variables. Tables and additional equations were developed that incorporate crown ratio for Douglas-fir, grand fir, and white fir. Equations that predict stump diameter, volume below breast height, and volume above breast height also are developed and presented for each species. Close