Effect of selective precommercial thinning on balsam fir stand yield and structure

2013 ◽  
Vol 89 (06) ◽  
pp. 759-768 ◽  
Author(s):  
Robert Schneider ◽  
Jean Bégin ◽  
Alain Danet ◽  
René Doucet
Keyword(s):  
Forest Management ◽  
Stand Structure ◽  
Balsam Fir ◽  
Precommercial Thinning ◽  
Thinning Intensity ◽  
Ecosystem Based Management ◽  
Silvicultural Treatments ◽  
And Control ◽  
Stand Yield ◽  
Diameter Distributions

Silvicultural tools such as green retention harvesting and multiple variations of partial cut systems are being developed to implement ecosystem-based forest management. However, very little effort has been expended in developing silvicultural treatments for young stands. Results for a selective precommercial thinning (three thinning intensities and control) covering a 28-year period in a balsam fir-dominated stand are presented. Thinning did not significantly increase stand yield, nor change stand diameter diversity or distribution. Furthermore, diameter distributions and diversity of dead stems also did not differ significantly (P > 0.05) among thinning intensity. More important than intensity effects, statistical differences were found between initial stand densities. Low initial densities had greater yields and more diverse diameter distributions. Nevertheless, for low initial stand densities, light to moderate thinning seemed to increase yield, whereas moderate to heavy thinnings would be appropriate for high initial stand densities. Although selective precommercial thinning does not result in significant changes in stand structure, it could be used as a first step in increasing stand complexity within the context of ecosystem-based management.

scholarly journals Stand Structure and Composition 32 Years after Precommercial Thinning Treatments in a Mixed Northern Conifer Stand in Central Maine

2011 ◽  
Vol 28 (2) ◽  
pp. 92-96 ◽  
Author(s):  
Aaron R. Weiskittel ◽  
Laura S. Kenefic ◽  
Rongxia Li ◽  
John Brissette
Keyword(s):  
Stand Structure ◽  
Abies Balsamea ◽  
Basal Area ◽  
Long Term Effects ◽  
Mixed Species ◽  
Precommercial Thinning ◽  
Large Trees ◽  
Stand Attributes ◽  
And Control

Abstract The effects of four precommercial thinning (PCT) treatments on an even-aged northern conifer stand in Maine were investigated by examining stand structure and composition 32 years after treatment. Replicated treatments applied in 1976 included: (1) control (no PCT), (2) row thinning (rowthin; 5-ft-wide row removal with 3-ft-wide residual strips), (3) row thinning with crop tree release (rowthin+CTR; 5-ft-wide row removal with crop tree release at 8-ft intervals in 3-ft-wide residual strips), and (4) crop tree release (CTR; release of selected crop trees at 8×8-ft intervals). PCT plots had more large trees and fewer small trees than the control in 2008. There were no other significant differences between the rowthin and control. The rowthin+CTR and CTR treatments had lower total and hardwood basal area (BA) and higher merchantable conifer BA than the control. CTR also resulted in more red spruce (Picea rubens [Sarg.]) and less balsam fir (Abies balsamea [L.]) than the other treatments. Although stand structures for rowthin+CTR and CTR were similar, the percentage of spruce in CTR was greater. Although the less-intensive rowthin+CTR treatment may provide many of the same benefits as CTR, the latter would be the preferred treatment if increasing the spruce component of a stand is an objective. Overall, early thinning treatments were found to have long-term effects on key stand attributes, even more than 30 years after treatment in areas with mixed species composition and moderate site potential.

scholarly journals Effect of long-term tending on qualitative and quantitative production in mixed stands of spruce, fir and beech on Motyky research plot

2012 ◽  
Vol 49 (No. 3) ◽  
pp. 108-124 ◽  
Author(s):  
I. Štefančík ◽  
L. Štefančík
Keyword(s):  
Stand Structure ◽  
Mixed Stands ◽  
Dynamic Changes ◽  
Tree Species Composition ◽  
Silvicultural Treatments ◽  
Altitudinal Zone ◽  
Control Dynamic ◽  
Crown Thinning ◽  
And Control

The paper is a contribution to research on thinnings in mixed (spruce-fir-beech) stands situated in the fifth forest altitudinal zone in the central part of Slovakia. Three plots were tended by free crown thinning while one plot was left without any planned silvicultural treatment (as a control). Dynamic changes in tree species composition, stand structure and quantitative production were evaluated for a period of 30 years. A special attention was paid to development of crop trees that are the main bearers of stand quality and quantity. The changes were compared with respect to differences between plots with long-term silvicultural treatments and control plot (without treatments).    

Optimierung forstlicher Produktion unter Beachtung von finanziellen Restriktionen | Optimisation of forest production under financial restrictions

2010 ◽  
Vol 161 (9) ◽  
pp. 346-354 ◽  
Author(s):  
Bernhard Möhring
Keyword(s):  
Forest Management ◽  
Evaluation Criteria ◽  
Opportunity Costs ◽  
Water Protection ◽  
Model Calculations ◽  
Thinning Intensity ◽  
Silvicultural Treatments ◽  
Forest Production ◽  
Forest Enterprises ◽  
Final Harvest

The question of efficiency of resources bound in the silvicultural (biological) production of forest enterprises strikes a central topic of forest management. Using simple spreadsheet calculation models, this paper tries to explicate the relations between silvicultural treatments and economic evaluation criteria under financial restrictions. By means of actual examples, concerning thinning intensity and final harvest age under the restriction of maintenance of capital, practical silvicultural behaviour can be seen as compatible with the optimal economic solutions, determined by the model calculations. This leads to the conclusion that commonly practiced concepts of thinning intensity and productivity dependent harvest age can be interpreted as rational economic behaviour. With reference to such an economic optimum the consequences of changes in forest management, as they are often claimed for instance by directives of nature conservation, water protection etc., can be evaluated based on opportunity costs.

scholarly journals A Novel Method for Evaluating Diversity of Stand Structure Based on Relationship of Adjacent Trees

2021 ◽  
Author(s):  
ZHONGHUA ZHAO ◽  
Gongqiao Zhang ◽  
Wenzhen Liu ◽  
Gangying Hui ◽  
Ganggang Zhang ◽  
...  
Keyword(s):  
Forest Management ◽  
Stand Structure ◽  
Structural Diversity ◽  
Structural Heterogeneity ◽  
Forest Types ◽  
Thinning Intensity ◽  
Stand Structural Diversity ◽  
Relationship Of ◽  
The Impact ◽  
D Value

Abstract Background Improving the diversity and complexity of stand structure is the basis for maintaining and increasing forest ecosystem biodiversity. Measures of stand structural diversity is important for predicting stand growth and evaluating forest management activities. Based on the relationship of adjacent trees, we present a new method for the quantitative analysis of stand structure diversity that allows comparison of stand structural heterogeneity between different stands and forest types and to quantify the impact of forest management on structural diversity. Method: The diversity of structural unit types was defined and then we derive a new index of forest structural diversity () according to the additivity principle of Shannon-Weiner index. The effectiveness and sensitivity to management were verified by sixteen field survey samples in different locations and six different simulated management datasets based on Pinus koraiensis broad-leaved forest survey sample. Results (1) The mountain rainforest in Hainan had the highest \({{S}^{\text{'}}}_{D}\) value at 5.287, followed by broad-leaved Korean pine forest in Jiaohe (2), Jiaohe (1) and oak broadleaved mixed natural forest in Xiaolongshan (2), with values of 5.144, 5.014 and 5.006, respectively. The \({{S}^{\text{'}}}_{D}\) values of plantations and natural pure forest were lower. (2) Different thinning methods and intensities reduced \({{S}^{\text{'}}}_{D}\) compared with no treatment and magnitude of the with the differences were greater as thinning intensity increased. The \({{S}^{\text{'}}}_{D}\) value of thinning from above decreased more than thinning from below at the same thinning intensity. Conclusion The\({{S}^{\text{'}}}_{D}\) well describes differences in stand structural diversity of different forest types and allows comparison of stand structural heterogeneity. It is also sensitive to forest management activities and to quantify the impact of forest management on structural diversity. The application of this new index \({{S}^{\text{'}}}_{D}\) could greatly facilitate forest management and monitoring.

Effects of precommercial thinning on the forest value chain in northwestern New Brunswick: Part 3 – Incidence of root and butt decay

2013 ◽  
Vol 89 (04) ◽  
pp. 464-473 ◽  
Author(s):  
Gary Warren ◽  
Patricia Baines ◽  
Jean Plamondon ◽  
Doug G. Pitt
Keyword(s):  
Forest Management ◽  
Value Chain ◽  
Abies Balsamea ◽  
Balsam Fir ◽  
Stand Age ◽  
Stem Form ◽  
Green River ◽  
Precommercial Thinning ◽  
Permanent Sample Plots ◽  
Butt Rot

The Green River precommercial thinning (PCT) trials were established between 1959 and 1961 in naturally regenerating balsam fir (Abies balsamea [L.] Mill.)-dominated stands an average of eight years after overstory removal. Three nominal spacings of 4 ft (1.2 m), 6 ft (1.8 m) and 8 ft (2.4 m) were compared to an unthinned control in six replicate blocks. In the fall of 2008, following completion of the ninth sequential evaluation of the study’s 48 permanent sample plots, three of the six replicates were clearcut harvested; butt rot data were collected immediately afterwards. To date, forest management research and goals have focused on the benefits of PCT, such as increased tree size and merchantable volume, shorter rotation ages, and better stem form and uniformity. Comparatively little attention has been placed on negative aspects of PCT, such as the incidence and development of root and butt rots, and their impact on fibre yields and wood product values. Results from the Green River study provide evidence that PCT may increase the incidence of butt rot in balsam fir, with incidence proportional to thinning intensity (p < 0.01). We also observed incidence and volume of butt rot to increase with stem diameter (p ≤ 0.05). The experiment suggests that factors such as stand age at time of thinning, and age at the time of harvest are important considerations when it comes to mitigating the impacts of butt rot through forest management.

scholarly journals A multiscale analysis of the effects of alternative silvicultural treatments on windthrow within balsam fir dominated stands

2015 ◽  
Vol 45 (12) ◽  
pp. 1739-1747 ◽  
Author(s):  
Kenneth Agbesi Anyomi ◽  
Jean-Claude Ruel
Keyword(s):  
Black Spruce ◽  
Abies Balsamea ◽  
Basal Area ◽  
Natural Disturbance ◽  
Balsam Fir ◽  
Partial Cutting ◽  
Selection Cutting ◽  
Silvicultural Treatments ◽  
Block Level ◽  
And Control

Boreal ecosystem functioning is largely controlled by disturbance dynamics. There have been efforts at adapting forest management approaches to emulate natural disturbance effects, as this is expected to maintain ecosystem resilience. In many instances, this involves resorting to partial cutting strategies that are likely to increase windthrow losses. The objective of this study was to determine the effects of alternative silvicultural practices on windthrow damage and how these effects vary with the scale of treatment. The study was conducted in the Quebec North Shore region (Canada), an area dominated by balsam fir (Abies balsamea (L.) Mill.) and accompanied by black spruce (Picea mariana (Mill) B.S.P.). Four different silvicultural treatments (overstory removal, heavy partial cutting, and two patterns of selection cutting) and control areas were implemented in 2004 and 2005. The experiment used a nested approach where treatment at the plot level was independent and yet nested within the block-level treatment. At the block level, treatments were applied over 10–20 ha units, leaving a small portion of the block for a smaller application of each treatment (plot scale, 2500 m2). Inventory was carried out before harvesting and monitoring was done yearly after harvesting, with the aim to better understand the plot- and block-level factors that drive windthrow damage levels and the effects of alternative silvicultural treatments. Results after 6–7 years show that basal area proportion windthrown differs substantially between treatments, as well as between treated sites and control sites. Windthrow levels were higher under heavy cuts relative to selection cuts and also increased with balsam fir proportion. Windthrow proportions were better correlated to block-level treatment than plot-level treatment, showing that the environment surrounding the treated plot can have an important effect on windthrow losses. Overall, the selection cutting system, particularly SC2, retains the most green-tree basal area and thus best meets the management objective of retaining old-growth attributes. A simple empirical model was calibrated that could aid in hazard rating.

scholarly journals Precommercial thinning of overtopping aspen to release coniferous regeneration in a boreal mixedwood stand

2017 ◽  
Vol 93 (03) ◽  
pp. 259-270 ◽  
Author(s):  
Marcel Prévost ◽  
Lise Charette
Keyword(s):  
Populus Tremuloides ◽  
Stand Structure ◽  
Early Stage ◽  
Vegetative Reproduction ◽  
Abies Balsamea ◽  
Acer Rubrum ◽  
Balsam Fir ◽  
Natural Succession ◽  
Precommercial Thinning ◽  
Stage Of Development

We used precommercial thinning (PCT) to accelerate natural succession in an 8-year-old, even-aged stratified mixture, in which trembling aspen (Populus tremuloides) overtopped a dense understory of balsam fir (Abies balsamea) and spruce (Picea mariana, P. glauca). In addition to an unthinned control, we applied three residual aspen spacings (2.5, 3.0 and 3.5 m) while retaining all understory conifers, and a 3.0-m spacing retaining only small conifers (<1/3 of the aspen crop tree height). PCT improved survival of spruce, increased diameter growth of aspen by 90% and doubled diameter and height growth of conifers, without differences among spacings or between levels of conifer retention after 10 years. The level of conifer retention did not affect aspen growth response, but appeared to influence the occurrence of browsing on aspen and balsam fir. Retaining only small conifers decreased regeneration density of balsam fir in favour of abundant vegetative reproduction of red maple (Acer rubrum) and beaked hazelnut (Corylus cornuta). Live crown characteristics and stand structure indicate that thinning caused a shift from overtopping of aspen to an intimate mixture of species sharing the growing space. This study confirms PCT as a means of accelerating natural succession in a boreal mixedwood stand, thereby securing the coniferous component at the early stage of development.

scholarly journals Precommercial Thinning Increases Spruce Yields in Boreal Mixedwoods in Alberta, Canada

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 412
Author(s):  
Ivan Bjelanovic ◽  
Phil Comeau ◽  
Sharon Meredith ◽  
Brian Roth
Keyword(s):  
Growth Models ◽  
Growth And Yield ◽  
Diameter Growth ◽  
Growth Responses ◽  
Projection System ◽  
Precommercial Thinning ◽  
Thinning Intensity ◽  
Boreal Mixedwoods ◽  
Using Data ◽  
Mixedwood Stands

A few studies in young mixedwood stands demonstrate that precommercial thinning of aspen at early ages can improve the growth of spruce and increase stand resilience to drought. However, information on tree and stand responses to thinning in older mixedwood stands is lacking. To address this need, a study was initiated in 2008 in Alberta, Canada in 14 boreal mixedwood stands (seven each at ages 17 and 22). This study investigated growth responses following thinning of aspen to five densities (0, 1000, 2500, 5000 stems ha−1 and unthinned (control)). Measurements were collected in the year of establishment, and three and eight years later. Mortality of aspen in the unthinned plots was greater than in the thinned plots which were not significantly different amongst each other. Eight years following treatment, aspen diameter was positively influenced by thinning, while there was no effect on aspen height. The density of aspen had no significant effect on the survival of planted spruce. Spruce height and diameter growth increased with both aspen thinning intensity and time since treatment. Differentiation among treatments in spruce diameter growth was evident three years from treatment, while differentiation in height was not significant until eight years following treatment. Yield projections using two growth models (Mixedwood Growth Model (MGM) and Growth and Yield Projection System (GYPSY)) were initialized using data from the year eight re-measurements. Results indicate that heavy precommercial aspen thinning (to ~1000 aspen crop trees ha−1) can result in an increase in conifer merchantable volume without reducing aspen volume at the time of harvest. However, light to moderate thinning (to ~2500 aspen stems ha−1 or higher), is unlikely to result in gains in either deciduous or conifer merchantable harvest volume over those of unthinned stands.

scholarly journals Implementation of Forest Conservation Policies based on Local Wisdom of the Ammatoa Kajang Indigenous Community

2021 ◽  
Vol 940 (1) ◽  
pp. 012082
Author(s):  
S Megawati ◽  
M A Mahdiannur
Keyword(s):  
Data Analysis ◽  
Forest Management ◽  
Forest Conservation ◽  
Indigenous Community ◽  
Cultural Authenticity ◽  
Conservation Policies ◽  
Study Approach ◽  
Monitoring Tools ◽  
Forestry Policies ◽  
And Control

Abstract The Ammatoa Kajang indigenous community maintain cultural authenticity from generation to generation, especially in protecting and preserving customary forests from the threat of damage. This research aims to describe the implementation of forest conservation policies based on local wisdom of the Ammatoa Kajang indigenous community. The research method uses a literature/library study approach. Reference documents from 2001-2021. Data analysis methods with data minimization, data visualization, data analysis, and data validation and concluding. The results of the research showed that the Kajang orthodox community in day-to-day forest management is guided by the Pasang ri Kajang, which contains rules, implementation and sanctions for all forms of forest utilization and management, monitoring tools and control over all activities related to forestry, positively correlated with forestry policies governance. The concept of customary forest management is to divide the forest into three areas with certain specifications and rules as well as prohibited from destroying flora and fauna. In the end, the forest is sustainable and indigenous community behave sustainably; it can be concluded that the implementation of forest conservation policies based on local wisdom of the Ammatoa Kajang indigenous community is going well.

scholarly journals Stand structure links up canopy processes and forest management

2009 ◽  
Vol 51 (1) ◽  
pp. 40-48
Author(s):  
Toomas Frey
Keyword(s):  
Forest Management ◽  
Stand Structure ◽  
Net Primary Production ◽  
Stand Density ◽  
Tree Height ◽  
Belowground Biomass ◽  
Unit Mass ◽  
Total Biomass ◽  
Individual Tree ◽  
Mean Values

Stand structure links up canopy processes and forest management Above- and belowground biomass and net primary production (Pn) of a maturing Norway spruce (Picea abies (L.) Karst.) forest (80 years old) established on brown soil in central Estonia were 227, 50 and 19.3 Mg ha correspondingly. Stand structure is determined mostly by mean height and stand density, used widely in forestry, but both are difficult to measure with high precision in respect of canopy processes in individual trees. However, trunk form quotient (q2) and proportion of living crown in relation to tree height are useful parameters allowing describe stand structure tree by tree. Based on 7 model trees, leaf unit mass assimilation activity and total biomass respiration per unit mass were determined graphically as mean values for the whole tree growth during 80 years of age. There are still several possible approaches not used carefully enough to integrate experimental work at instrumented towers with actual forestry measurement. Dependence of physiological characteristics on individual tree parameters is the missing link between canopy processes and forest management.

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