scholarly journals Predicting Quaking Aspen Stand Dynamics in Minnesota

1993 ◽  
Vol 10 (1) ◽  
pp. 20-27
Author(s):  
Rolfe A. Leary ◽  
Gary J. Brand ◽  
Donald A. Perala
Keyword(s):  
Relative Density ◽  
Basal Area ◽  
Site Index ◽  
Density Change ◽  
Permanent Plots ◽  
Stand Dynamics ◽  
Quaking Aspen ◽  
Modeling Methodology ◽  
The Future ◽  
Yield Table

Abstract This paper presents equations for predicting future basal area, number of trees, and total cubic-foot volume of aspen stands in Minnesota. The modeling methodology uses a fully-stocked yield table for quaking aspen as a density standard. A relative density change equation based on observed growth from permanent plots provides the basis for predicting the future relative density and therefore the future basal area, number of trees, and volume. The equations are easy to apply and require only site index, age, and beginning basal area, number of trees, and volume. North. J. Appl. For. 10(1):20-27.

scholarly journals A Simple Technique for Estimating Board Foot Volume Yields in Appalachian Hardwoods

2006 ◽  
Vol 23 (3) ◽  
pp. 211-214
Author(s):  
John R. Brooks ◽  
Harry V. Wiant
Keyword(s):  
Simple Technique ◽  
Basal Area ◽  
Site Index ◽  
Parameter Estimates ◽  
Separate Model ◽  
Yield Table ◽  
Input Variables ◽  
Table Data ◽  
Stand Yield ◽  
Appalachian Hardwoods

Abstract A simple whole stand yield equation based solely on basal area per acre for sawtimber-sized trees and average dominant height was found to provide reasonably accurate estimates of board foot (International) yield in Appalachian hardwoods. Separate parameter estimates were obtained for mesophytic hardwood and mixed oak remeasurement plot data and the yield tables of Schnur (Schnur, G.L. 1937. Yield, stand and volume tables for even-aged upland oak forests. USDA Tech. Bull. 560). Estimates of board foot yield per acre for the remeasurement plot data were within 10% of observed values for stands over 30 years old and within 5% for stands over 45 years old. A separate model form based on the same two input variables was developed for Schnur’s yield table data for site index classes 50–80. Estimates of board foot yield were within 10% of tabular values for stands over 45 years old, regardless of site index class.

Pascal's recurrence relation and even-aged-forest stand dynamics

1992 ◽  
Vol 22 (12) ◽  
pp. 1996-1999
Author(s):  
Rolfe A. Leary ◽  
Hien Phan ◽  
Kevin Nimerfro
Keyword(s):  
Differential Equation ◽  
Relative Density ◽  
Closed Form ◽  
Initial Conditions ◽  
Closed Form Solution ◽  
Integral Form ◽  
Forest Stand ◽  
Form Solution ◽  
Density Change ◽  
Stand Dynamics

A common method of modelling forest stand dynamics is to use permanent growth plot remeasurements to calibrate a whole-stand growth model expressed as an ordinary differential equation. To obtain an estimate of future conditions, either the differential equation is integrated numerically or, if analytic, the differential equation is solved in closed form. In the latter case, a future condition is obtained simply by evaluating the integral form for the age of interest, subject to appropriate initial conditions. An older method of modelling forest stand dynamics was to use a normal or near-normal yield table as a density standard and calibrate a relative density change equation from permanent plot remeasurements. An estimate of a future stand property could be obtained by iterating from a known initial relative density. In this paper we show that when the relative density change equation has a particular form, the historical method also has a closed form solution, given by a sequence of polynomials with coefficients from successive rows of Pascal's arithmetic triangle.

Test of the TRIM inventory projection methods on Wisconsin jack pine

1990 ◽  
Vol 20 (6) ◽  
pp. 774-780 ◽  
Author(s):  
Rolfe A. Leary ◽  
W. Brad Smith
Keyword(s):  
Relative Density ◽  
Volume Growth ◽  
Projection Methods ◽  
Jack Pine ◽  
Density Change ◽  
Growth Data ◽  
Projection System ◽  
Yield Table ◽  
Unbiased Estimates ◽  
Annual Volume

Reported is a test of the methodology underlying the trim projection system being used in the Resources Planning Act timber assessment. Nine combinations of density standards and relative density change equations were used to estimate annual volume growth of jack pine (Pinusbanksiana Lamb.). Annual volume growth data from remeasured USDA Forest Service inventory plots in two northern Wisconsin survey units and from industrial continuous forest inventory plots were used to evaluate the combinations. The yield table of Gevorkiantz and Duerr for well-stocked jack pine stands combined with a Riccati relative density change equation gave unbiased estimates of annual volume growth on both an absolute and percent error basis. We conclude that the concepts underlying the TRIM methodology are sound. However, for jack pine in northern Wisconsin only well-stocked or normal yield tables as the density standard and locally calibrated relative density change equations provide unbiased estimates of growth. A jack pine empirical yield table combined with the form of the relative density change equation used in the southern timber supply study underestimated growth by 45.4% (1.39 m3/(ha•year)). An empirical yield table enhanced with the STEMS projection system as a density standard used without a relative density change equation underestimated growth by 65.6% (1.67 m3/(ha•year)). Thus, inappropriate combinations of density standards and relative density change equations may lead to large errors in growth estimates.

Near-normal, empirical, and identity yield tables for estimating stand growth

1991 ◽  
Vol 21 (3) ◽  
pp. 353-362 ◽  
Author(s):  
Rolfe A. Leary
Keyword(s):  
Relative Density ◽  
Growth Models ◽  
Jack Pine ◽  
Forest Growth ◽  
Density Change ◽  
Simple Function ◽  
Initial Relative Density ◽  
Stand Growth ◽  
Yield Table ◽  
Identity Based

Historically, forest growth was estimated using a normal or near-normal yield table as a density standard, and a relative density change equation to estimate approach to the standard. Although normal yield tables have come under intense criticism, critics have generally ignored the relative density change equation. If a yield table captures the "true" relations between volume, age, and site for a species, the relative density change equation can be a simple function of initial relative density and age. If a yield table does not capture the true relations between volume, site, and age, the inadequacy can be overcome by developing more complex relative density change equations, i.e., by transferring representation burden to the change equation. Introduced in the present paper is the concept of an identity yield table (all entries are one), wherein the entire burden of representing the relations between volume, site, and age is transferred from a density standard to a relative density change equation. Modern whole stand (net) growth models are equivalent to historical relative density change equations based on identity yield tables. The conjecture of a continuum of methods to estimate growth from near-normal to empirical to identity yield tables, each with an appropriate relative density change equation, and each equally accurate, is tested on Wisconsin jack pine (Pinusbanksiana Lamb.). The empirical yield table and its relative density change equation were more biased than near-normal and identity-based projection systems.

scholarly journals Volume and Value Growth of Hardwood Trees in Wisconsin

1993 ◽  
Vol 10 (2) ◽  
pp. 63-69 ◽  
Author(s):  
Joseph Buongiorno ◽  
Jiing-Shyang Hseu
Keyword(s):  
Forest Type ◽  
Volume Growth ◽  
Basal Area ◽  
Site Index ◽  
Red Oak ◽  
Quaking Aspen ◽  
High Grade ◽  
Inventory Analysis ◽  
Significance Level ◽  
Value Growth

Abstract The volume of healthy trees of commercial size in the maple-birch forest type measured during the last two Forest Inventory Analysis surveys of Wisconsin grew at 2 to 3%/yr for sawtimber, and 3 to 4% for poletimber, with substantial differences among species. However, from 1967 to 1989, the real price of logs decreased or remained constant for most grades and species. The decrease was especially large for high grade logs. The only exceptions were red oak and elm, whose prices increased at 1 to 2%/yr, for all grades. As a result, the average value growth rate of the trees that did not improve in grade was a modest 2%/yr, and not different from zero at a 5% significance level. Holding high grade trees led to substantial losses. Red oak and elm provided good returns because of favorable price trends, and quaking aspen because of its fast volume growth. Among the worst financial performers were hard and soft maple and yellow birch, the most numerous trees in the sample. A simple equation was derived to predict volume growth rates as a function of tree diameter, site index, crown ratio, stand basal area, crown dominance, and tree species. Although these variables did influence volume growth, suggesting that silvicultural practices could be beneficial, they explained only a small part of volume growth, and less of value growth. The future of commercial forestry in Wisconsin depends at least as much on policies that will develop markets and obtain good prices as on improved silviculture. North. J. Appl. For. 10(2): 63-69.

scholarly journals GENERAL HEIGHT-DIAMETER EQUATION WITH BIOLOGICAL ATTRIBUTES FOR Pinus taeda L. STANDS

CERNE ◽  
2017 ◽  
Vol 23 (4) ◽  
pp. 403-411 ◽  
Author(s):  
Saulo Jorge Téo ◽  
Sebastião do Amaral Machado ◽  
Afonso Figueiredo Filho ◽  
Margarida Tomé
Keyword(s):  
Linear Function ◽  
Pinus Taeda ◽  
Basal Area ◽  
Site Index ◽  
Permanent Plots ◽  
General Applicability ◽  
West Region ◽  
Biological Attributes ◽  
Middle West ◽  
Pinus Taeda L

ABSTRACT The aim of this study was to develop an equation with biological attributes and general applicability, to represent the height-diameter relationship for Pinus taeda L. stands, with and without thinning, in the Middle West region of Santa Catarina state, Brazil. The data came from 652 permanent plots, with 428 to 740 m2, located in forest stands with ages ranging from 4.6 to 35.2 years, in which the total heights of about 20% of the trees were measured, in addition to the dominant trees. The functions developed by Harrison, Michailoff, Prodan and Stoffels & Van Soest were fitted with their parameters linear function of stand variables, based on the Gauss-Newton algorithm. In general, the Harrison model, fitted with the parameter linear function of age (t), site index (S), coefficient of variation of the tree diameters in the plot (CV d ) and basal area of the plot (G), showed the best statistical performance to represent the height-diameter relationship, biological consistency and general applicability for stands of Pinus taeda.

Preliminary DRIS norms for coastal Douglas-fir soils in Washington and Oregon

1995 ◽  
Vol 25 (2) ◽  
pp. 208-214 ◽  
Author(s):  
J.S. Shumway ◽  
H.N. Chappell
Keyword(s):  
Basal Area ◽  
Site Index ◽  
Douglas Fir ◽  
Integrated System ◽  
N Fertilizer ◽  
Soil Test ◽  
Fertilizer Response ◽  
Response Data ◽  
Limiting Nutrient ◽  
Diagnostic Work

The Diagnosis and Recommendation Integrated System (DRIS) has been used successfully in agricultural crops and holds promise for use in forest stands. This study used soil tests to develop DRIS norms and evaluate their effectiveness in coastal Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) forests. DRIS norms for nitrogen, phosphorus, potassium, and calcium were developed using soil test and site index data from 72 soil series that commonly support Douglas-fir in western Washington. The norms were tested using soil test and stand basal area growth response data from 20 thinned and 30 unthinned N fertilizer test sites in coastal Washington and Oregon. Response to urea fertilizer in thinned stands averaged 34% and 43% for 224 and 448 kg N•ha−1, respectively, when N was identified as the most limiting nutrient. When N was not the most limiting nutrient, N response averaged 8% and 10% for 224 and 448 kg N•ha−1, respectively. Results were similar in unthinned stands and thinned stands, although response to fertilizer appeared to be slightly less in unthinned stands when N was the most limiting nutrient. DRIS correctly classified 25 of the 33 sites (76%) where N fertilizer increased growth by more than 15%. More importantly, 13 of the 17 (76%) sites that responded by less than 15% were correctly identified by DRIS. The results clearly indicate that N fertilizer response is dependent on the interactions (balance) between soil nutrients at a given site. Future soil diagnostic work needs to focus on techniques, like DRIS, that provide an assessment of these interactions.

A Growth and Yield Model for Improved Eastern Cottonwood Plantations in the Lower Mississippi Delta

1991 ◽  
Vol 15 (4) ◽  
pp. 213-216 ◽  
Author(s):  
Quang V. Cao ◽  
Kenneth M. Durand
Keyword(s):  
Populus Deltoides ◽  
Mississippi Delta ◽  
Basal Area ◽  
Site Index ◽  
Growth And Yield ◽  
Annual Increment ◽  
Yield Model ◽  
Eastern Cottonwood ◽  
Volume Yield ◽  
Growth And Yield Model

Abstract A compatible growth and yield model was developed based on remeasurement data collected from 183 plots on unthinned improved eastern cottonwood (Populus deltoides Bartr.) plantations in the lower Mississippi Delta. The Sullivan and Clutter (1972) equation form was selected for predicting cubic-foot volume yield and projecting volume from site index and initial age and basal area. Yield equations explained 97% and 94%, respectively, of the variations in total outside bark and merchantable inside bark volumes. Mean annual increment of merchantable volume culminated between 8 and 15 years, depending on site index and initial basal area. South. J. Appl. For. 15(4):213-216.

scholarly journals DENSITY MANAGEMENT DIAGRAM FOR Eucalyptus grandis W. Hill. ex Maiden STANDS CONTROLLED BY DOMINANT HEIGHT

FLORESTA ◽  
2020 ◽  
Vol 51 (1) ◽  
pp. 240
Author(s):  
Gabriel Paes Marangon ◽  
Emanuel Arnoni Costa ◽  
César Augusto Guimarães Finger ◽  
Paulo Renato Schneider ◽  
Matheus Teixeira Martins
Keyword(s):  
Eucalyptus Grandis ◽  
Strong Relationship ◽  
Site Index ◽  
Graphical Analysis ◽  
Coefficient Of Determination ◽  
Permanent Plots ◽  
Volume Number ◽  
Dominant Height ◽  
Development Site ◽  
Relationship Of

Density management diagram for eucalyptus stands controlled by dominant height. The present study aimed to elaborate Density Management Diagrams (DMD) for Eucalyptus grandis W. Hill. ex Maiden stands including the dominant height. Data were obtained from permanent plots installed in the Centro Oriental Riograndense region and the Porto Alegre Metropolitan area, both located in the state of Rio Grande do Sul. The models to describe the relationships between average volume, number of trees per hectare, mean diameter, and dominant height were assessed by the statistical criteria of coefficient of determination (R²), standard error of the estimate in percentage (Syx%), and graphical analysis of residuals. The developed DMD allows for a better control of stocks in the management of stands due to the strong relationship of dominant height with stand development site and forest yield.Keywords: Growth, Site index, Forest regulation, Yield.

scholarly journals Stand-Level Components of a Growth and Yield Model for Nothofagus Mixed Forests from Southern Chile

Forests ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 810
Author(s):  
Sebastian Palmas ◽  
Paulo C. Moreno ◽  
Wendel P. Cropper ◽  
Alicia Ortega ◽  
Salvador A. Gezan
Keyword(s):  
Forest Type ◽  
Geographical Area ◽  
Basal Area ◽  
Forest Growth ◽  
Model Systems ◽  
Growth And Yield ◽  
Permanent Plots ◽  
Stand Age ◽  
Yield Model ◽  
Mixed Forests

Reliable information on stand dynamics and development is needed to improve management decisions on mixed forests, and essential tools for this purpose are forest growth and yield (G&Y) models. In this study, stand-level G&Y models were built for cohorts within the natural mixed second-growth Nothofagus-dominated forests in Chile. All currently available (but limited) data, consisting of a series of stratified temporary and permanent plots established in the complete range of this forest type, were used to fit and validate these models. Linear and nonlinear models were considered, where dominant stand age, number of trees, and the proportion of basal area of Nothofagus species resulted in significant predictors to project future values of stand basal area for the different cohorts (with R2 > 0.51 for the validation datasets). Mortality was successfully modeled (R2 = 0.79), based on a small set of permanent plots, using the concept of self-thinning with a proposed model defined by the idea that, as stands get closer to a maximum density, they experience higher levels of mortality. The evaluation of these models indicated that they adequately represent the current understanding of dynamics of basal area and mortality of Nothofagus and companion species in these forests. These are the first models fitted over a large geographical area that consider the dynamics of these mixed forests. It is suggested that the proposed models should constitute the main components of future implementations of G&Y model systems.

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