Download or read book Predicting Height to Crown Base for Undamaged and Damaged Trees in Southwest Oregon written by Mark L. Hanus and published by . This book was released on 2000 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Equations for predicting height to crown base are presented for tree species from southwest Oregon. Equations for undamaged and damaged trees were estimated with weighted nonlinear regression techniques. The effects of specific damaging agents on the height to crown base were explored, and damage correction factors were estimated. The damage correction factors can be used to correct the predicted crown ratio for specific damaging agents and their severity in samples where damage is noted. These equations are being incorporated into the new southwest Oregon version of ORGANON (ORegon Growth ANalysis and projectiON), a model for predicting the growth of individual trees in forest stands. The equations extend the past model to older stands and stands with a heavier component of hardwood tree species.

Download or read book Predicting Height for Crown Base for Undamaged and Damaged Trees in Southwest Oregon by Mark L Hanus David W Hann David D Marshall written by Mark L. Hanus and published by . This book was released on 2000 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Predicting Height for Undamaged and Damaged Trees in Southwest Oregon written by Mark L. Hanus and published by . This book was released on 1999 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Predicting Height for Undamaged and Damaged Trees in Southwest Oregon by M L Hanus D W Hann D D Marshall written by M. L. Hanus and published by . This book was released on 1999 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Enhanced Height growth rate Equations for Undamaged and Damaged Trees in Southwest Oregon written by David W. Hann and published by . This book was released on 2002 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Equations for Predicting Height to Crown Base for Fourteen Tree Species in Southwest Oregon written by Martin W. Ritchie and published by . This book was released on 1987 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Enhanced Diameter growth rate Equations for Undamaged and Damaged Trees in Southwest Oregon written by David W. Hann and published by . This book was released on 2002 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Equations for Predicting the Height to Crown Base of Six Tree Species in the Central Western Willamette Valley of Oregon written by Abdel Azim Zumrawi and published by . This book was released on 1989 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Forest Growth and Yield Modeling written by Aaron R. Weiskittel and published by John Wiley & Sons. This book was released on 2011-08-22 with total page 431 pages. Available in PDF, EPUB and Kindle. Book excerpt: Forest Growth and Yield Modeling synthesizes current scientific literature and provides insights in how models are constructed. Giving suggestions for future developments, and outlining keys for successful implementation of models the book provides a thorough and up-to-date, single source reference for students, researchers and practitioners requiring a current digest of research and methods in the field. The book describes current modelling approaches for predicting forest growth and yield and explores the components that comprise the various modelling approaches. It provides the reader with the tools for evaluating and calibrating growth and yield models and outlines the steps necessary for developing a forest growth and yield model. Single source reference providing an evaluation and synthesis of current scientific literature Detailed descriptions of example models Covers statistical techniques used in forest model construction Accessible, reader-friendly style

Download or read book Equations for Predicting Height to crown base 5 year Diameter growth Rate 5 year Height growth Rate 5 year Mortality Rate and Maximum Size density Trajectory for Douglas fir and Western Hemlock in the Coastal Region of the Pacific Northwest written by David W. Hann and published by . This book was released on 2003 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using existing permanent research plot data, we developed equations for predicting height-to-crown-base (HCB), 5-yr diametergrowth rate (delta D), 5-yr height-growth rate (delta H), 5-yr mortality rate (PM), and the maximum size-density trajectory for Douglasfir and western hemlock in the coastal region of the Pacific Northwest. With the exception of the HCB equation, the equations developed for predicting trees from untreated plots agreed in predictive behavior with previously published equations for the study area. The HCB equation predicted shorter HCB (and therefore longer crown lengths [CL]) than previously published equations for the study area. Western hemlock showed no response to fertilization. Modifiers for fertilization response were incorporated into the final equations for predicting delta D, delta H, and PM in Douglas-fir. All three modifiers for Douglas-fir predicted an increase in growth and mortality rates with the amount of nitrogen applied and a decrease with number of years since fertilization, with most of the fertilization effect gone within 15 yr of application. For the delta D and delta H modifiers, the size of the increase varied by the site index (SI) of the plot, with plots of lower site quality showing greater increases. For delta D, fertilization response did not appear to vary by plot density, tree size, or tree position within the plot. Modifiers for thinning response were incorporated into the final equations for predicting tree delta D for both species and delta H for Douglas-fir. For both species, the delta D thinning-effects modifier predicted an increased growth rate with the proportion of the BA removed and a decrease with years since thinning; most of the thinning effect was gone within 10 yr. For Douglas-fir, the delta H thinning-effects modifier predicted a reduced growth rate immediately after thinning, with the size of the reduction increasing with the intensity of thinning. Most of the reduction was gone by about 10 yr. For Douglas-fir, the combined effect on delta D and delta H of applying both thinning and fertilization could be adequately characterized by the product of the thinning modifier and the fertilization modifier. The percent increase in predicted growth rate due to a combined treatment thus was greater than the sum of the percent increases for each treatment alone. Analysis of the maximum size-density trajectory data strongly suggests that plots of neither species approach a single maximum stand density index value (SDI) as they develop. The potential yield for a given site therefore depends, not only on its SI, but also on its maximum SDI. Fertilization does not appear to affect the intercept of the maximum size-density line for Douglas-fir. The strengths and weaknesses of the existing data sets and the modeling and analytical approaches tested during development of these equations are presented to aid future modelers, and alternative modeling approaches are explored.

Download or read book Equations for Predicting the Largest Crown Width of Stand grown Trees in Western Oregon written by David W. Hann and published by . This book was released on 1997 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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).

Download or read book Predicting Height Increment of Young growth Red Fir in California and Southern Oregon written by K. Leroy Dolph and published by . This book was released on 1992 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: An equation is given to estimate 10-year height increment for young-growth red fir trees in California and southern Oregon. The independent variables are the individual tree, stand, and site characteristics significantly related to a tree's height growth. Data used to develop the equation came from stem analysis of 492 trees sampled from 56 stands in the study area. Parameter estimates for the predictive equation were obtained using least-squares linear regression.

Download or read book Environmental Modelling written by John Wainwright and published by John Wiley & Sons. This book was released on 2013-04-01 with total page 493 pages. Available in PDF, EPUB and Kindle. Book excerpt: Simulation models are an established method used to investigate processes and solve practical problems in a wide variety of disciplines. Central to the concept of this second edition is the idea that environmental systems are complex, open systems. The authors present the diversity of approaches to dealing with environmental complexity and then encourage readers to make comparisons between these approaches and between different disciplines. Environmental Modelling: Finding Simplicity in Complexity 2nd edition is divided into four main sections: An overview of methods and approaches to modelling. State of the art for modelling environmental processes Tools used and models for management Current and future developments. The second edition evolves from the first by providing additional emphasis and material for those students wishing to specialize in environmental modelling. This edition: Focuses on simplifying complex environmental systems. Reviews current software, tools and techniques for modelling. Gives practical examples from a wide variety of disciplines, e.g. climatology, ecology, hydrology, geomorphology and engineering. Has an associated website containing colour images, links to WWW resources and chapter support pages, including data sets relating to case studies, exercises and model animations. This book is suitable for final year undergraduates and postgraduates in environmental modelling, environmental science, civil engineering and biology who will already be familiar with the subject and are moving on to specialize in the field. It is also designed to appeal to professionals interested in the environmental sciences, including environmental consultants, government employees, civil engineers, geographers, ecologists, meteorologists, and geochemists.

Download or read book Equations for Predicting the Height to Crown Base of Six Tree Species in the Central Western Williamette Valley of Oregon written by Abel Azim Zumrawi and published by . This book was released on 1989 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book General Technical Report PNW GTR written by and published by . This book was released on 2002 with total page 1074 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Enhanced Mortality Equations for Trees in the Mixed Conifer Zone of Southwest Oregon written by David W. Hann and published by . This book was released on 2001 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Construction of Regression Models for Predicting Crown Development in Southwestern Oregon Douglas fir written by Douglas Alan Maguire and published by . This book was released on 1986 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: A branch mortality dating technique and whorl sampling strategy were implemented to model five-year crown recession from data collected on temporary plots. Twenty-eight Douglas-fir from two levels-of-growing- stock studies in Oregon and Washington were first dissected to validate the proposed dating technique and assess alternative sampling strategies. Branch mortalities in 10-15 whorls below crown base were dated by locating discontinuities between branch and bole growth rings in stem cross-sections. Along with height measurements to the sample whorls, this technique allowed reconstruction of past crown base positions. Backdated heights to crown base corresponded closely with 15-year repeat crown measurements taken on the same trees. Seven sampling strategies (sampling scheme and estimator) were assessed for their ability to estimate past five-year crown recession by sampling only two to four whorls per tree. Simple linear regressions of estimated on actual recession for various five-year intervals suggested that a two-whorl sampling scheme with an appropriate estimator would perform adequately on temporary growth plots. This sampling strategy was applied to 357 Douglas-fir from temporary growth plots in southwestern Oregon. Numerous nonlinear and logarithmic models were developed to predict five-year crown recession from other tree, stand, and site variables. Residual analyses and indices of fit demonstrated that a multiplicative model with lognormal errors was the most appropriate model form. Sapwood taper above breast height was modeled with a quadratic-quadratic segmented polynomial. This taper function allowed extrapolation or interpolation of sapwood area measurements near crown base to sapwood area at crown base. Transformation of gross crown dimensions into expressions of conic surface area yielded accurate predictions of sapwood area at crown base. These expressions were therefore inferred to reflect equally well the total leaf area of individual Douglas-fir trees in southwestern Oregon. Modeling at the resolution of gross crown dimensions therefore possesses both the physiological appeal of providing an accurate index of the tree's relative photosynthetic capacity and the conceptual appeal of portraying competition for light and aerial growing space.