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

  Equations for predicting the 5-yr diameter-growth rate of a tree are presented for eight conifer and nine hardwood tree species from southwest Oregon. Equation parameters for undamaged and damaged trees ...

  Citation × Citation Citation Abstract Copy Title: Enhanced diameter-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 diameter-growth rate of a tree are presented for eight conifer and nine hardwood tree species from southwest Oregon. Equation parameters for undamaged and damaged trees combined were estimated by weighted nonlinear regression. The resulting equation for Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] explained more than 71% of the variation when validated against an independent data set. These equations are being incorporated into the new edition of ORGANON for southwest Oregon, a model for predicting the development of stands. The equations extend the previous model to older stands and stands with a larger component of hardwood. We explored the effects of specific damaging agents on the 5-yr diameter-growth rates of the five most frequently encountered species and estimated damage correction factors. Damaging agents can impact 5-yr diameter-growth rate significantly and, as a result, can lead over time to diversification in stand structure. Therefore, full characterization of stand development should include prediction of the presence and frequency of the agents damaging trees within the stand and their impact on tree attributes such as total height, height-to-crown-base, diameter-growth rate, height-growth rate, and mortality rate. Title: Enhanced diameter-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 diameter-growth rate of a tree are presented for eight conifer and nine hardwood tree species from southwest Oregon. Equation parameters for undamaged and damaged trees combined were estimated by weighted nonlinear regression. The resulting equation for Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] explained more than 71% of the variation when validated against an independent data set. These equations are being incorporated into the new edition of ORGANON for southwest Oregon, a model for predicting the development of stands. The equations extend the previous model to older stands and stands with a larger component of hardwood. We explored the effects of specific damaging agents on the 5-yr diameter-growth rates of the five most frequently encountered species and estimated damage correction factors. Damaging agents can impact 5-yr diameter-growth rate significantly and, as a result, can lead over time to diversification in stand structure. Therefore, full characterization of stand development should include prediction of the presence and frequency of the agents damaging trees within the stand and their impact on tree attributes such as total height, height-to-crown-base, diameter-growth rate, height-growth rate, and mortality rate. Close

• 2. [Article] Enhanced mortality equations for trees in the mixed conifer zone of Southwest Oregon

  Equations for predicting the probability of a tree's dying in the next 5 years are presented for eight conifer and eight hardwood tree species from southwest Oregon. A logistic equation form was used to ...

  Citation × Citation Citation Abstract Copy Title: Enhanced mortality equations for trees in the mixed conifer zone of Southwest Oregon Author: Hanus, Mark L., Oregon State University. Forest Research Laboratory, Hann, David W. Equations for predicting the probability of a tree's dying in the next 5 years are presented for eight conifer and eight hardwood tree species from southwest Oregon. A logistic equation form was used to characterize the probability of mortality. The parameters of the equation were estimated using weighted, maximum likelihood procedures. These equations are being incorporated into the new southwest Oregon version of ORGANON, a model for predicting stand development. In particular, the equations extend the previous model to older stands and and stands with a heavier component of hardwood tree species. Title: Enhanced mortality equations for trees in the mixed conifer zone of Southwest Oregon Author: Hanus, Mark L., Oregon State University. Forest Research Laboratory, Hann, David W. Equations for predicting the probability of a tree's dying in the next 5 years are presented for eight conifer and eight hardwood tree species from southwest Oregon. A logistic equation form was used to characterize the probability of mortality. The parameters of the equation were estimated using weighted, maximum likelihood procedures. These equations are being incorporated into the new southwest Oregon version of ORGANON, a model for predicting stand development. In particular, the equations extend the previous model to older stands and and stands with a heavier component of hardwood tree species. Close

• 3. [Article] Equations for predicting the 5-year height growth of six conifer species in southwest Oregon

  Equations for predicting individual-tree height growth per 5-year period are presented for Douglas-fir, white fir, grand fir, ponderosa pine, sugar pine, and incense-cedar growing in the mixed-conifer ...

  Citation × Citation Citation Abstract Copy Title: Equations for predicting the 5-year height growth of six conifer species in southwest Oregon Author: Ritchie, Martin W., Oregon State University. Forest Research Laboratory, Hann, David W. Equations for predicting individual-tree height growth per 5-year period are presented for Douglas-fir, white fir, grand fir, ponderosa pine, sugar pine, and incense-cedar growing in the mixed-conifer zone of southwest Oregon. The data used to develop the equations came from 3,648 trees sampled from 391 stands in the study area. Parameters were estimated by means of nonlinear regression. The model for height growth is expressed as a function of site index, total tree height, crown ratio, and percentage of crown closure at total height of the subject tree. Title: Equations for predicting the 5-year height growth of six conifer species in southwest Oregon Author: Ritchie, Martin W., Oregon State University. Forest Research Laboratory, Hann, David W. Equations for predicting individual-tree height growth per 5-year period are presented for Douglas-fir, white fir, grand fir, ponderosa pine, sugar pine, and incense-cedar growing in the mixed-conifer zone of southwest Oregon. The data used to develop the equations came from 3,648 trees sampled from 391 stands in the study area. Parameters were estimated by means of nonlinear regression. The model for height growth is expressed as a function of site index, total tree height, crown ratio, and percentage of crown closure at total height of the subject tree. Close