The influence of competition on individual white pine thinning response

1986 ◽  
Vol 16 (6) ◽  
pp. 1355-1359 ◽  
Author(s):  
Andrew R. Gillespie ◽  
Harold W. Hocker Jr.

A model predicting white pine (Pinusstrobus L.) diameter growth after thinning included competition, initial diameter, and crown class as independent variables. Model coefficients indicated a decrease in percent 8-year diameter growth with increasing crown suppression, crown competition, or tree size class. Variables selected were superior to age, percent live crown, and prethinning growth. Equations predicting basal area and volume growth were similar in form to diameter growth. Height growth, however, was more closely correlated with crown characteristics and unaffected by competition. Annual growth patterns were similar to periodic growth patterns, revealing decreased growth with increasing competition or crown suppression. Trees having little competition and dominant crowns utilized their growing season longer, with earlier initial growth and faster growth than trees having greater competition or crown suppression. Within a crown class, diameter growth decreased as competition increased. Individual tree competition was seen as the most important factor influencing tree growth that a forester can control.

2000 ◽  
Vol 30 (5) ◽  
pp. 753-760 ◽  
Author(s):  
Arthur Groot ◽  
Hannu Hökkä

The persistence of suppression effects on peatland black spruce (Picea mariana (Mill.) BSP) advance regeneration following overstory removal was examined (i) by analyzing post-harvest growth patterns and (ii) by comparing observed post-harvest growth with predictions from an individual-tree growth model. Analysis of growth patterns revealed critical points (inflections or maxima) in annual basal area, diameter, and height growth series, and in specific volume increment. Critical points occurred at different times (ranging from 1 to 29 years after harvest) for different variables and often occurred earlier for trees with greater height at time of harvest. These critical points do not necessarily coincide with the cessation of persisting suppression, however, since post-harvest growth patterns also reflect current influences on growth. The comparison of observed basal area and diameter growth with model predictions isolated persisting suppression effects. The effects of suppression on basal area and diameter growth decline linearly with time since harvest and become negligible 12 years after harvest. The persistence of suppression effects on basal area and diameter growth is largely independent of the height of the tree at the time of harvest.


2001 ◽  
Vol 25 (1) ◽  
pp. 31-39 ◽  
Author(s):  
James S. Meadows ◽  
J.C.G. Goelz

Abstract A 21 ac, 28-yr-old water oak (Quercus nigra L.) plantation, on an old-field loessial site in north Louisiana, was subjected to three thinning treatments during the winter of 1987–1988: (1) no thinning, (2) light thinning to 180 dominant and codominant trees/ac, and (3) heavy thinning to 90 dominant and codominant trees/ac. Prior to thinning, the plantation averaged 356 trees/ac and 86 ft2/ac of basal area, with a quadratic mean diameter of 6.7 in. Thinning reduced stand basal areas to 52 and 34 ft2/ac for the light and heavy thinning treatments, respectively. After 5 yr, both thinning treatments increased diameter growth rates of individual residual trees, both when all trees were considered and when the analysis was limited to dominant and codominant trees only. Neither thinning treatment affected either stand-level volume growth or total yield 5 yr after treatment. However, thinning distributed total volume growth among fewer trees, such that, when trees of all crown classes were considered in the analysis, average annual volume growth per tree increased with increasing intensity of thinning. Both basal area growth and volume growth following light thinning appear to be sufficient to promote rapid recovery of the stand to a fully stocked condition in the near future. In contrast, heavy thinning reduced density to a severely understocked condition that will prohibit optimum occupancy of the site for a long period. Among the treatments evaluated in this study, light thinning produced the most desirable combination of individual-tree diameter growth and stand-level basal area growth. South. J. Appl. For. 25(1):31–39.


2000 ◽  
Vol 24 (2) ◽  
pp. 112-120 ◽  
Author(s):  
Michael M. Huebschmann ◽  
Lawrence R. Gering ◽  
Thomas B. Lynch ◽  
Onesphore Bitoki ◽  
Paul A. Murphy

Abstract A system of equations modeling the growth and development of uneven-aged shortleaf pine (Pinus echinata Mill.) stands is described. The prediction system consists of two main components: (1) a distance-independent, individual-tree simulator containing equations that forecast ingrowth, basal-area growth, probability of survival, total and merchantable heights, and total and merchantable volumes and weights of shortleaf pine trees; and (2) stand-level equations that predict hardwood ingrowth, basal-area growth, and mortality. These equations were combined into a computer simulation program that forecasts future states of uneven-aged shortleaf pine stands. Based on comparisons of observed and predicted stand conditions in shortleaf pine permanent forest inventory plots and examination of the growth patterns of hypothetical stands, the simulator makes acceptable forecasts of stand attributes. South. J. Appl. For. 24(2):112-120.


2001 ◽  
Vol 31 (12) ◽  
pp. 2059-2066 ◽  
Author(s):  
Brian J Stanton

Two-year periodic basal area increments (PBAI) of short-rotation Populus stands were followed through a 6-year rotation in monoclonal plots at three sites to assess variation in response patterns among 20 Populus trichocarpa Torr. & Gray × Populus deltoides Bartr. clones. Data were analyzed using a split-plot model for repeated measurements with the main effect of time and the time × clone interaction partitioned into their linear and quadratic orthogonal components. The form of the mean clone growth response was mainly quadratic with PBAI culminating during the second period at 145–160% of the rotation mean. Increments fell to 95–116% of the rotation mean during the following period. Response variation occurred mainly in the degree of linearity at two sites with clones varying in the rate of growth deceleration during the third period, while quadratic response variation was of prime importance at the third site. Changes in basal area levels among the topmost clones over the last stage of stand development were associated with the divergence in the linear and quadratic responses. Selection on the basis of interaction contrasts of periodic growth from monoclonal plot trials is discussed in terms of sustaining yield improvements and maintaining adaptation to short rotation strategies.


1991 ◽  
Vol 8 (2) ◽  
pp. 83-85
Author(s):  
Robert K. Shephard ◽  
Gregory A. Reams ◽  
Ronald C. Lemin

Abstract Plots were established in nine eastern white pine stands; six on outwash soils and three on till soils. Nitrogen was applied to the plots at rates of 0, 50, 100, and 200 lb/ac. Four-year growth response functions for basal area/ac and merchantable cubic ft volume/ac were developed. Basal area growth was 9.2 ft²/ac greater and volume growth was 235 ft³/ac greater on the till soils compared with the outwash soils, regardless of application rate Both basal area and volume growth increased as basal area/ac increased. Maximum basal area response, 5.7 ft²/ac, and maximum volume response, 198 ft³/ac, was estimated to occur at an application rate of approximately 160 lb of nitrogen/ac, with incremental response being greater at lower application rates. Fertilization at a rate of approximately 100 lb of nitrogen/ac appears to be a cost effective practice for many white pine stands. North. J. Appl. For. 8(2):83-85.


2019 ◽  
Vol 65 (6) ◽  
pp. 784-795
Author(s):  
Jeffrey S Ward ◽  
Jessica Wikle

AbstractSix study areas were established in 80–125-year-old upland oak stands on average sites to compare stand and individual tree growth response following two active treatments (B-level thinning, crop tree) with an unmanaged control. Initial stocking of 104 percent was reduced to 62 percent and 60 percent on the B-level and crop-tree-management plots, respectively. Approximately 7,200 board feet per acre (International ¼) were harvested on the actively managed plots with upland oaks accounting for 81 percent of pre- and 86 percent of residual stand. Eleven-year diameter and volume growth of oak sawtimber trees was greater on actively managed plots. Growth response increased with degree of release and was maintained for the length of the study. Because of the increased individual tree growth of oaks in response to release, stand volume growth of oak sawtimber did not differ between treatments. In contrast to an 11-year decline of poletimber stocking on unmanaged plots, poletimber stocking increased on managed plots as diameter growth increased in response to partial release. This may increase difficulty of regenerating oak in the future. For those mature red oak stands where traditional regeneration prescriptions will not be implemented or will be delayed, commercial harvests can be conducted without compromising stand volume growth of oak.


2008 ◽  
Vol 25 (4) ◽  
pp. 186-194 ◽  
Author(s):  
Don C. Bragg

Abstract By adapting data from national and state champion lists and the predictions of an existing height model, an exponential function was developed to improve tree height estimation. As a case study, comparisons between the original and redesigned model were made with eastern white pine (Pinus strobus L.). For example, the heights predicted by the new design varied by centimeters from the original until the pines were more than 25 cm dbh, after which the differences increased notably. On a very good site (50-year base age site index [SI50] = 27.4 m) at the upper end of the range of basal area (BA; 68.9 m2/ha) for the region, the redesigned model predicted a champion-sized eastern white pine (actual measurements: 97.0 cm dbh, 50.9 m tall) to be 51.3 m tall, compared with 38.8 m using the original formulation under the same conditions. The NORTHWDS Individual Response Model (NIRM) individual tree model further highlighted the influence of these differences with long-term simulations of eastern white pine height. On a moderate site (SI50 = 18.7 m) with intermediate (BA = 15 m2/ha) stand density, NIRM results show that the original model consistently predicts heights to be 20–30% lower for mature white pine.


2010 ◽  
Vol 40 (5) ◽  
pp. 843-849 ◽  
Author(s):  
John B. Bradford ◽  
Anthony W. D’Amato ◽  
Brian J. Palik ◽  
Shawn Fraver

Growth dominance is a relatively new, simple, quantitative metric of within-stand individual tree growth patterns, and is defined as positive when larger trees in the stand display proportionally greater growth than smaller trees, and negative when smaller trees display proportionally greater growth than larger trees. We examined long-term silvicultural experiments in red pine ( Pinus resinosa Ait.) to characterize how stand age, thinning treatments (thinned from above, below, or both), and stocking levels (residual basal area) influence stand-level growth dominance through time. In stands thinned from below or from both above and below, growth dominance was not significantly different from zero at any age or stocking level. Growth dominance in stands thinned from above trended from negative at low stocking levels to positive at high stocking levels and was positive in young stands. Growth dominance in unthinned stands was positive and increased with age. These results suggest that growth dominance provides a useful tool for assessing the efficacy of thinning treatments designed to reduce competition between trees and promote high levels of productivity across a population, particularly among crop trees.


1996 ◽  
Vol 26 (2) ◽  
pp. 327-331 ◽  
Author(s):  
Paul A. Murphy ◽  
Michael G. Shelton

Tree basal area growth has been modeled as a combination of a potential growth function and a modifier function, in which the potential function is fitted separately from open-grown tree data or a subset of the data and the modifier function includes stand and site variables. We propose a modification of this by simultaneously fitting both a growth component and a modifier component. The growth component can be any function that approximates tree growth patterns, and the logistic function is chosen as the modifier component. This approach can be adapted to a variety of stand conditions, and its application is demonstrated using data from an uneven-aged loblolly pine (Pinustaeda L.) study located in Arkansas and Louisiana.


1999 ◽  
Vol 14 (3) ◽  
pp. 144-148 ◽  
Author(s):  
Gregory M. Filip ◽  
Stephen A. Fitzgerald ◽  
Lisa M. Ganio

Abstract A 30-yr-old stand of ponderosa pine was precommercially thinned in 1966 to determine the effects of thinning on tree growth and mortality caused by Armillaria root disease in central Oregon. After 30 yr, crop tree mortality was significantly (P = 0.02) less in thinned plots than in unthinned plots. Tree diameter growth was not significantly (P = 0.17) increased by thinning. Crop-tree basal area/ac growth was significantly (P = 0.03) greater in thinned plots. Apparently, from a root disease perspective, precommercial thinning of pure ponderosa stands significantly decreases the incidence of crop-tree mortality after 30 yr and significantly increases basal area/ac growth but not individual tree diameter growth. Recommendations for thinning based on stand density index (SDI) are given. West. J. Appl. For. 14(3):144-148.


Sign in / Sign up

Export Citation Format

Share Document