scholarly journals Calibrating a Segmented Taper Equation with Two Diameter Measurements

2009 ◽  
Vol 33 (2) ◽  
pp. 58-61 ◽  
Author(s):  
Quang V. Cao
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Polynomial Regression ◽  
Stem Diameter ◽  
Laser Technology ◽  
Breast Height ◽  
Tree Data ◽  
Pinus Taeda L ◽  
Taper Equation ◽  
Taper Equations

Abstract Recent advances in laser technology help make possible accurate and affordable measurements of upper-stem diameters. These measurements can be used to calibrate results from a taper equation to improve the accuracy of diameter predictions along the tree bole. Felled-tree data from a loblolly pine (Pinus taeda L.) plantation were used to evaluate two methods for calibrating outputs from a segmented taper equation with parameters either obtained from the data in this study or originally published by <xref ref-type="bibr" rid="B5-2124">Max and Burkhart (1976</xref>, Segmented polynomial regression applied to taper equations, For. Sci. 22:283–289). For outside-bark diameters, although a simple calibration for dbh gave desirable results, a better calibration involving both dbh and an upper-stem diameter provided significant improvements in predicting tree taper. Results varied depending on where the diameter was measured, with optimum gains obtained when the upper-stem diameter was measured at the midpoint between breast height and the tree tip. For inside-bark diameters, the calibration for inside-bark dbh actually produced inferior predictions, whereas the calibration based on both dbh and an upper-stem diameter offered only modest improvements over the unadjusted predictions.

Tree Volume and Taper of Loblolly Pine Varies by Stand Origin

1987 ◽  
Vol 11 (4) ◽  
pp. 185-189 ◽  
Author(s):  
Ralph L. Amateis ◽  
Harold E. Burkhart
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Analysis Data ◽  
Old Field ◽  
Stem Analysis ◽  
Tree Form ◽  
Pinus Taeda L ◽  
Natural Stands ◽  
Taper Equations ◽  
Forest Managers

Abstract Stem analysis data were used to examine volume, height-dbh, form and taper relationships for loblolly pine (Pinus taeda L.) trees grown in unthinned old-field plantations, cutover-site plantations, and natural stands. Results showed significant differences in volume, height-dbh, tree form and taper relationships for loblolly pine grown in stands from these three origins. Thus, in order to accurately predict total and merchantable volumes as well as upper stem diameters and heights, forest managers should apply separate volume and taper equations for each stand class. South. J. Appl. For. 11(4):185-189.

scholarly journals Volume and Taper Equations for Thinned and Unthinned Loblolly Pine Trees in Cutover, Site-Prepared Plantations

1997 ◽  
Vol 21 (3) ◽  
pp. 146-152 ◽  
Author(s):  
Gudaye Tasissa ◽  
Harold E. Burkhart ◽  
Ralph L. Amateis
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Analysis Data ◽  
The South ◽  
Stem Analysis ◽  
Pine Trees ◽  
Pinus Taeda L ◽  
Taper Equations ◽  
Volume Equations

Abstract Stem analysis data from loblolly pine (Pinus taeda L.) trees grown in cutover, site-prepared plantations across the South were used to develop total and merchantable cubic-foot volume equations and implicit taper relationships for thinned and unthinned conditions. The data were obtained from trees felled during plot establishment for a thinning study and from trees felled during the second thinning of a portion of the same plots 12 yr later. The volume equations presented can be used to predict volume to any specified height or diameter limit for loblolly pine trees in thinned and unthinned stands on cutover site-prepared areas. The taper relationships enable the prediction of upper stem diameters and heights. South. J. Appl. For. 21(3):146-152.

scholarly journals Deriving compatible taper functions from volume ratio equations based on upper-stem height

2017 ◽  
Vol 47 (10) ◽  
pp. 1424-1431 ◽  
Author(s):  
Thomas B. Lynch ◽  
Dehai Zhao ◽  
Will Harges ◽  
John Paul McTague
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Volume Ratio ◽  
Stem Volume ◽  
Stem Height ◽  
Ratio Data ◽  
Prediction Systems ◽  
Pinus Taeda L ◽  
Taper Equations ◽  
Tree Stem

A very common model for prediction of tree stem volumes to upper-stem height or diameter limits is the use of a merchantable to total volume ratio function multiplied by a total stem volume function. Many users of these prediction systems also desire taper equations that can predict heights to upper-stem diameters. While taper equations compatible with volume ratio equations have been used for many years, compatible taper equations from volume ratio equations that are functions of upper-stem height have been used infrequently. Yet many studies have indicated that height-based ratio equations perform well and frequently have statistics of fit that are comparable with diameter-based volume ratio equations. Compatible taper equations derived from height-based ratio equations are presented here. The methodology that uses height-based merchantable to total volume ratios does not require the solution of a differential equation after differentiating the height-based volume ratio, as is necessary when using the method of deriving taper equations from diameter-based merchantable to total volume ratios. This could be an advantage depending on the complexity of the ratio function. Example taper equations fitted to loblolly pine (Pinus taeda L.) data from the southeastern USA and the state of Oklahoma, USA, indicate good fit to these data, whether fitted directly to taper data or implicitly by using parameters fitted to volume ratio data.

Identification of representative sampling heights for specific gravity and moisture content in plantation-grown loblolly pine (Pinus taeda)

2012 ◽  
Vol 42 (3) ◽  
pp. 574-584 ◽  
Author(s):  
Finto Antony ◽  
Laurence R. Schimleck ◽  
Richard F. Daniels
Keyword(s):  
Specific Gravity ◽  
Moisture Content ◽  
Pinus Taeda ◽  
Loblolly Pine ◽  
Wood Properties ◽  
Representative Sampling ◽  
Breast Height ◽  
Sampling Height ◽  
Pinus Taeda L ◽  
Whole Tree

Conventionally, increment cores collected at breast height (1.4 m) have been used to measure wood properties of standing loblolly pine (Pinus taeda L.) trees. This height has been used because of the ease of sampling and cost involved in extracting the cores. In this study, the efficacy of a breast-height core to represent whole-tree specific gravity (SG) and moisture content (MC) was examined. The sampling height that best represents whole-tree SG and MC was identified using the correlation between volume-weighted whole-tree SG and MC with SG and MC measurements collected at different heights within a tree. We found a high correlation between observed whole-disk SG and MC with volume-weighted whole-tree SG and MC at most sampling heights. The strength of the correlation followed a skewed parabolic curve form for both wood properties. The strongest correlations were observed between 4.6 and 6.1 m, with marginally lower correlations at the base of the tree, and the weakest correlations were observed towards the tip of the tree. In addition, it was found that the number of stands and trees that need to be sampled to achieve a certain accuracy in overall mean whole-tree SG and MC was greater if breast height was used as a sampling height compared with the most representative sampling heights identified (4.6 m for SG and 6.1 m for MC).

A Comparison of the Effects of One-Step and Two-Step Pruning on Loblolly Pine Stem Form

1986 ◽  
Vol 10 (4) ◽  
pp. 251-253 ◽  
Author(s):  
Michael A. Valenti ◽  
Quang V. Cao
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Probability Level ◽  
Stem Form ◽  
Form Class ◽  
Significant Difference ◽  
One Step ◽  
Two Measures ◽  
Pinus Taeda L ◽  
Taper Equation

Abstract The effects of one-step and two-step pruning treatments on tree taper of loblolly pine (Pinus taeda L.) were compared in this study. Girard form class and a segmented taper equation were used as two measures of stem form. There was a significant difference in stem form between trees subjected to one-step and two-step pruning treatments at the 5% probability level. Trees pruned at ages 6 and 11 tapered less and yielded about 4% more cubic-foot volume and 9% more board-foot volume than trees pruned at age 11 of comparable diameters and heights. South. J. Appl. For. 10:251-253, Nov. 1986.

Response Following Aerial Applications of Glyphosate for Release of Loblolly Pine in the Virginia Piedmont

1988 ◽  
Vol 12 (1) ◽  
pp. 54-58 ◽  
Author(s):  
Bruce R. Zutter ◽  
Patrick J. Minogue ◽  
Dean H. Gjerstad
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Growth Curves ◽  
Late Summer ◽  
Red Maple ◽  
Breast Height ◽  
Growing Seasons ◽  
Relative Composition ◽  
Virginia Piedmont ◽  
Pinus Taeda L

Abstract Four growing seasons after aerial applications of glyphosate at 1.0, 1.5 or 2.0 lb ai/ac in a three-year-old loblolly pine (Pinus taeda L.) plantation in late summer, diameter at breast height (dbh) and total height of pines were greater on treated compared to untreated areas. Pines on treated plots averaged 2.5 in. dbh and 15.2 ft in height while pines on untreated plots averaged 1.9 in. dbh and 13.5 ft in height. Height growth curves of treated pines through four growing seasons following treatment. In general, reduction in hardwood density and pine response each increased with increasing glyphosate rate. Relative composition of red maple in the stand increased two years after treatment for all rates of glyphosate, but did not change in the plots without treatment. South. J. Appl. For. 12(1):54-58.

Spacing rectangularity effect on the growth of loblolly pine plantations

2002 ◽  
Vol 32 (8) ◽  
pp. 1451-1459 ◽  
Author(s):  
Mahadev Sharma ◽  
Harold E Burkhart ◽  
Ralph L Amateis
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Basal Area ◽  
Planting Density ◽  
Stand Development ◽  
Crown Width ◽  
Pine Trees ◽  
Tree Data ◽  
Initial Spacing ◽  
Pinus Taeda L

The effect of spacing rectangularity on tree growth and stand development was evaluated using tree data obtained annually from a loblolly pine (Pinus taeda L.) spacing trial monitored through age 16 years. In this trial, plots with an initial planting density of 2240 trees/ha occur at slightly and highly rectangular spacings. Spacings with rectangularities 3:4 and 1:3 were used to evaluate the rectangularity effect. Survival and the development of height, diameter, volume per hectare, and basal area per hectare of loblolly pine trees were not affected by rectangularity. Diameter and height distributions were found to be a function of age but not a function of the rectangularity of initial spacing. Crown width, however, was affected by rectangularity. The crown width was larger at larger row or column distance than at smaller row or column distance, but the ratio of crown widths between and within rows was not equal to the rectangularity of the original planting spacing.

The effect of spacing rectangularity on stem quality in loblolly pine plantations

2004 ◽  
Vol 34 (2) ◽  
pp. 498-501 ◽  
Author(s):  
Ralph L Amateis ◽  
Philip J Radtke ◽  
Gerald D Hansen
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Pine Plantations ◽  
Planting Density ◽  
Breast Height ◽  
Stem Quality ◽  
Using Data ◽  
Pinus Taeda L ◽  
Branch Size ◽  
Tree Stem

The effect of spacing rectangularity on tree stem quality was evaluated using data collected from a loblolly pine (Pinus taeda L.) spacing trial measured at age 19. In this trial, bole condition, branch size, and stem asymmetry were examined on plots with an initial planting density of 2240 trees/ha planted at slight (3:4) and greater (1:3) rectangular spacings to determine suitability for sawtimber production. Results indicated that rectangularity had no significant effect on survival or the number of potential sawtimber trees by age 19. While the 1:3 spacing treatment had a significantly larger maximum branch size than the 3:4 spacing treatment, it could not be attributed to the within-row or between-row direction. Additional measurements on stem diameter at breast height within and between rows failed to show stem asymmetry in the 1:3 spacing treatment. Consequently, rectangular spacings up to 1:3 should not have much impact on overall stem quality.

Ten-year growth comparison between rooted cuttings and seedlings of loblolly pine

1998 ◽  
Vol 28 (1) ◽  
pp. 69-73 ◽  
Author(s):  
H E Stelzer ◽  
G S Foster ◽  
V Shaw ◽  
J B McRae
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Seedling Height ◽  
Rooted Cuttings ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Breast Height ◽  
Stem Taper ◽  
Sib Families ◽  
Pinus Taeda L

Rooted cuttings and seedlings of loblolly pine (Pinus taeda L.) were established in a central Alabama field trial. Five, full-sib families, with an average number of six clones per family, were evaluated. Mean cutting/seedling height ratios revealed that despite initial differences in size, relative growth rates of both propagule types stabilized and were equal by age 7 years. Through age 10 years, results show virtually no difference in height, diameter at breast height, volume, or stem taper between the rooted cuttings and seedlings.

Dimensionally compatible volume and taper equations

2001 ◽  
Vol 31 (5) ◽  
pp. 797-803 ◽  
Author(s):  
Mahadev Sharma ◽  
Richard G Oderwald
Keyword(s):  
North Carolina ◽  
Loblolly Pine ◽  
Coastal Plain ◽  
Pine Trees ◽  
Volume Equation ◽  
Pinus Taeda L ◽  
Taper Equation ◽  
Natural Stands ◽  
Taper Equations ◽  
Volume Equations

A dimensional analysis approach was applied to derive analytically consistent tree taper and volume equations. To achieve numerical consistency between the taper and volume equations, parameters of the taper and the volume equations were estimated simultaneously. Data from loblolly pine (Pinus taeda L.) trees grown in natural stands in the Coastal Plain of North Carolina and the Coastal Plain and Piedmont areas of Virginia were used to estimate the parameters. The dimensionally compatible volume equation is shown to be a better equation for estimation of the volume of loblolly pine trees grown in these sites and can be applied for the estimation of total volume. The taper equation accurately predicts tree diameters from butt to the tree tip. It can be used to predict the diameter at any specified height and to predict height to any top diameter limit.

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