VB merch-slash: A growth-and-yield prediction system with a merchandising optimizer for planted slash pine in the west Gulf region

2005 ◽  
Author(s):  
S.J. Chang ◽  
Rodney L. Busby ◽  
P.R. Pasala ◽  
Jeffrey C. Goelz
1988 ◽  
Vol 12 (4) ◽  
pp. 239-242 ◽  
Author(s):  
J. David Lenhart

Abstract Procedures and methods for a diameter-distribution yield-prediction system for young (4-20 years old) unthinned loblolly (Pinus taeda L.) and slash pine (Pinus elliotti Englem.) plantations on non-old-fields in East Texas are presented. Average height and number of trees are predictors of minimum diameter, arithmetic mean diameter, and quadratic mean diameter. The three measures of diameter are then used to determine the parameters of a Weibull probability density function. After obtaining the function, the number of trees by diameter class can be calculated, and by using individual tree content equations, expected yield by diameter class can be computed. An evaluation of the system indicated that on the average, loblolly pine plantation yields were underestimated by 5.3% and slash pine plantation yields were underestimated by 8.1%. Computer programs written in FORTRAN and BASIC are available from the author for the diameter-distribution yield-prediction system. South. J. App. For. 12(4):239-242


2008 ◽  
Vol 32 (2) ◽  
pp. 89-94 ◽  
Author(s):  
Dean W. Coble ◽  
Young-Jin Lee

Abstract A parameter recovery procedure for the Weibull distribution function based on four percentile equations was used to develop a new diameter distribution yield prediction model for unmanaged slash pine (Pinus elliottii Engelm.) plantations in East Texas. This new model was similar in structure to the model of Lee and Coble (Lee, Y.J., and D.W. Coble. 2006. A new diameter distribution model for unmanaged loblolly pine plantations in east Texas. South. J. Appl. For. 30(1):13–20) in their work with East Texas loblolly pine plantations. The new model was compared with the diameter distribution model of Lenhart (Lenhart, J.D. 1988. Diameter distribution yield prediction system for unthinned loblolly and slash pine plantations on non-old-fields in east Texas. South. J. Appl. For. 12(4):239–242. 1988), which was developed for slash pine plantations in East Texas, as well as to two other models developed using iterative techniques suggested and inspired by Cao (Cao, Q. 2004. Predicting parameters of a Weibull function for modeling diameter distribution. For. Sci. 50(5):682–685). The model developed in this study was preferred over Lenhart (Lenhart 1988) and the other two models in prediction of total trees per acre, basal area per acre, quadratic mean diameter, and cubic-foot volume per acre (wood and bark, excluding stump). An example also is provided to show users how to use this new yield prediction system. We recommend that the model developed in this study be used to estimate growth and yield of East Texas slash pine plantations.


2006 ◽  
Vol 30 (3) ◽  
pp. 132-141 ◽  
Author(s):  
Dean W. Coble ◽  
Keith Hilpp

Abstract The Max-Burkhart taper equation was used to develop compatible taper and volume equations for semi-intensive plantation grown loblolly pine (Pinus taeda L.) trees in East Texas. Semi-intensive plantations in East Texas are characterized by some form of mechanical site preparation,a burn, possibly chemical weed control, improved seedlings if planted after 1985, and, possibly, a midrotation thinning and/or fertilization. The equations in this study were compared with those of Lenhart et al. [Lenhart, J.D., T.L. Hackett, C.J. Laman, T.J. Wiswell, and J.A. Blackard.1987. Tree content and taper functions for loblolly and slash pine trees planted on non-old field in east Texas. South J. Appl. For. 10(2)109–112.] and Baldwin and Feduccia [Baldwin, V.C. Jr., and D.P. Feduccia. 1991. Compatible tree-volume and upper-stem diameter equationsfor loblolly and slash pines in the West Gulf Region. South. J. Appl. For. 10(2)109–112.] using independent data. The new equations ranked first (sum of ranks = 9) in terms of percent bias and percent SEE for inside-bark predictions of upper-stem diameters and cubic-footvolumes, while the Lenhart et al. [Lenhart, J.D., T.L. Hackett, C.J. Laman, T.J. Wiswell, and J.A. Blackard. 1987. Tree content and taper functions for loblolly and slash pine trees planted on non-old field in east Texas. South J. Appl. For. 10(2)109–112.] ranked second (sumof ranks = 17) and Baldwin and Feduccia [Baldwin, V.C. Jr., and D.P. Feduccia. 1991. Compatible tree-volume and upper-stem diameter equations for loblolly and slash pines in the West Gulf Region. South. J. Appl. For. 10(2)109–112.] ranked third (sum of ranks =22). For outside-bark predictions of volumes and diameters, Baldwin and Feduccia [Baldwin, V.C. Jr., and D.P. Feduccia. 1991. Compatible tree-volume and upper-stem diameter equations for loblolly and slash pines in the West Gulf Region. South. J. Appl. For. 10(2)109–112.] rankedfirst (sum of ranks = 12), while the new equations ranked a close second (sum of ranks = 13) and Lenhart et al. [Lenhart, J.D., T.L. Hackett, C.J. Laman, T.J. Wiswell, and J.A. Blackard. 1987. Tree content and taper functions for loblolly and slash pine trees planted onnon-old field in east Texas. South J. Appl. For. 10(2)109–112.] ranked third (sum of ranks = 20). We recommend using the new equations for loblolly pine trees up to a 16-in. dbh and provide examples to illustrate their use. South. J. Appl.For. 30(3):142–146.


1981 ◽  
Vol 5 (2) ◽  
pp. 59-62 ◽  
Author(s):  
Leon V. Pienaar ◽  
Barry D. Shiver

Abstract Survival functions are derived for site-prepared slash pine plantations in the flatwoods of Georgia and northern Florida. Two functions are presented. The first is a function which may be used with any planting-survival count or estimate. This function is probably most useful in conjunction with available yield-prediction systems (with stems/acre as an input) to evaluate alternative management strategies. The second function, the difference equation form of the first function, is most useful in predicting future growth and yield based on inventory data.


Sign in / Sign up

Export Citation Format

Share Document