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• 1. [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

• 2. [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