scholarly journals The proposition of optimal silvicultural-reclamation operations in untended beech stands of mixed origin

2004 ◽  
pp. 155-170 ◽  
Author(s):  
Milun Krstic
Keyword(s):  
Stand Structure ◽  
Basal Area ◽  
The State ◽  
Stand Development ◽  
Tree Removal ◽  
Volume Increment ◽  
Diameter Structure ◽  
Mixed Origin ◽  
State Quality ◽  
Biological Differentiation

The state, quality, spontaneous development and silvicultural demands of untended beech stands of mixed origin were studied, the age of trees in the dominant layer is about 75 years. The analysis of stand development through a 17-year period (1986-2003) included the monitoring of the elements of stand structure: Number of trees, basal area, volume, diameter and volume increment, mean stand diameter, structure, mortality and tree removal from the stand, morphological, biological and technical characteristics of trees and biological differentiation of trees. The adequate silvicultural-reclamation measures are proposed based on the identified stand state.

scholarly journals Development of artificially established spruce stand at the site of mountain beech after intensive selection thinning

2004 ◽  
pp. 63-75
Author(s):  
Martin Bobinac
Keyword(s):  
Basal Area ◽  
The State ◽  
Sample Plot ◽  
Height Increment ◽  
Current Volume ◽  
Volume Increment ◽  
The Future ◽  
Permanent Sample Plot

The effects of selection thinning were analyzed at a permanent sample plot in the artificially established spruce stand aged 32 years, on the site of mountain beech. The state in the 32-year-old stand was as follows: 3911 trees per ha, basal area 57.5 m2ha-1 and volume 378.3 m3ha-1. Selection thinning removed 1378 tree per ha (35.2%) and 110 m3ha-1 (29.2%), and in the period between the ages of 32 and 40 years, predominantly because of mortality, another 550 trees per ha and 21.8 m3ha-1. On the remaining trees during the period between the ages of 32 and 40 years, basal area increased by 33%, and volume by 67%. Current volume increment was 20.7 m3ha-1 and it was concentrated on the future trees (28% of the total number of trees produces 52% of volume increment). The disproportion in the intensity of diameter and height increment after the thinning resulted in the increase of form quotient.

scholarly journals Simulating Multiaged Coast Redwood Stand Development: Interactions between Regeneration, Structure, and Productivity

2009 ◽  
Vol 24 (1) ◽  
pp. 24-32 ◽  
Author(s):  
John-Pascal Berrill ◽  
Kevin L. O'Hara
Keyword(s):  
Stand Structure ◽  
Basal Area ◽  
Stand Density ◽  
Site Index ◽  
Growth And Yield ◽  
Stand Development ◽  
Area Index ◽  
Coast Redwood ◽  
Stand Growth ◽  
Upper Limit

Abstract Multiaged management regimes and harvesting scenarios were simulated in coast redwood (Sequoia sempervirens [D. Don.] Endl.) stands using models of stand growth and yield (CRYPTOS) and stocking assessment (redwood MASAM). Various stocking and age-class combinations were modeled on site index 100 and 130 ft (50 years). Results demonstrated how the number of cohorts, upper limit of stocking, and cohort densities affected growth and yield. Board foot volume increment reached a plateau in stands with a prescribed upper limit of stocking above leaf area index 7.2 to 8.6. Productivity did not differ between stands with two to five cohorts producing the same tree size at harvest. It was affected by stand structure when a cutting cycle of 20 years was prescribed in stands with three to five cohorts. Stands with the same density returned to the upper limit of stocking much sooner on better sites. Prolonging the cutting cycle by reducing stand density resulted in larger tree sizes at harvest and greater productivity. The growth of trees remaining after cutting 10–50% of stand basal area and growth of new stump sprouts were also simulated. Stands quickly returned to preharvest stocking after light cutting, implying that heavy or frequent light cutting is needed to sustain growth and vigor of regeneration in multiaged coast redwood stands.

scholarly journals Evaluating tree-to-tree competition during stand development in a relict Scots pine forest: how much does climate matter?

Trees ◽  
2021 ◽  
Author(s):  
Laura Marqués ◽  
J. Julio Camarero ◽  
Miguel A. Zavala ◽  
Markus Stoffel ◽  
Juan A. Ballesteros-Cánovas ◽  
...  
Keyword(s):  
Scots Pine ◽  
Stand Structure ◽  
Climatic Variability ◽  
Basal Area ◽  
Climatic Conditions ◽  
Climate Impacts ◽  
Stand Development ◽  
Relict Population ◽  
Competition Effects ◽  
Over Time

Abstract Key message Competitive interactions change over time and their influence on tree growth is intensified during drought events in marginal Scots pine populations. Abstract Competition is a key factor driving forest dynamics and stand structure during the course of stand development. Although the role of neighbourhood competition on stand dynamics has received increasing attention, the response of competition to environmental fluctuations and stand development remains poorly explored. We evaluated changes in competition during stand development in a dry-edge Scots pine relict population located in Central Spain. Typically, tree-to-tree interactions have been investigated through static competition measurements, which usually lack the temporal variation associated to natural forest development and environmental conditions. Here, we assessed how individual and neighbourhood components of competition evolved along a 35-year period, and we related competition dynamics to population structure and drought levels. On six plots, 508 trees were mapped and diameters at breast height (DBH) were measured. Two increment cores were taken from target trees to derive basal area increment (BAI), and neighbourhood was reconstructed back to 1980. Results provide insights into inter-annual variability in competition effects and their role on tree radial growth depending on climatic conditions. From the year 2005 onwards, both individual and neighbourhood components of competition showed a decoupled pattern over time. This effect was particularly pronounced during the extreme drought in 2012, in which the individual component decreased, whereas the neighbourhood component increased. In addition, climatic variability modulated the competition effects during stand development. This approach of evaluating competition dynamics proves to be promising for studying forest stand development and the influence of climate impacts on tree populations subjected to xeric conditions.

scholarly journals Impact of a spruce budworm outbreak in balsam fir and subsequent stand development over a 40-year period

2008 ◽  
Vol 84 (1) ◽  
pp. 60-69 ◽  
Author(s):  
David A MacLean ◽  
Allison R Andersen
Keyword(s):  
Stand Structure ◽  
Abies Balsamea ◽  
Basal Area ◽  
Stand Density ◽  
Spruce Budworm ◽  
Balsam Fir ◽  
Stand Development ◽  
Wide Range ◽  
Break Up ◽  
The Impact

Nine 0.04-ha plots were established in 1956 (age 35 years) in a balsam fir (Abies balsamea [L.] Mill.) stand in northwestern New Brunswick, Canada to determine the impact of an uncontrolled spruce budworm (Choristoneura fumiferana [Clem.]) outbreak on stand development. The plots were measured annually from 1956 to 1961 and at five-year intervals from 1965 to 1995. Moderate to severe defoliation occurred from 1951 to 1957 and again in 1975 to 1977, 1981, and 1986 to 1988. Budworm-caused mortality from 1956 to 1961 (age 35 to 40 years) varied considerably among plots, reducing volume by 35 to 113 m3/ha (34%-84%), and resulting in a wide range of post-outbreak plot densities. Plots were grouped into three post-budworm outbreak (1965, age 45 years) basal area classes, of ≤ 20 m2/ha, 21 to 27 m2/ha, and ≥ 28 m2/ha, to examine stand recovery. Recovery of volume up to age 60 years ranged from 72 to 132 m3/ha, in the lowest to highest basal area classes, respectively. From age 60 to 75 years, five plots declined in volume due to the onset of stand break-up and four plots increased in volume. By age 60 years, survivor growth was greatest in the high basal area plots, ranging from 6.2 to 9.0 m3/ha/yr in seven plots, versus 2.6 to 3.2 m3/ha/yr in two low basal area plots. From age 60 to 75 years, survivor growth averaged only 2.8 to 5.2 m3/ha/yr, and the stand exhibited major decline, with 63%, 74%, and 78% mortality of fir ≤ 15 cm DBH in the low to high basal area plots, respectively. Budworm-caused "thinning" in the 1950s largely determined subsequent stand development and the rate of stand break-up 25 to 35 years later. The timing and rate of natural stand decline was strongly influenced by post-outbreak stand density. Key words: budworm-caused mortality, stand structure, stand development, growth, mortality, stand density

scholarly journals Stand state, silvicultural demands and measures in beech forests of mixed origin in Boljevac area

2004 ◽  
pp. 171-183 ◽  
Author(s):  
Milun Krstic ◽  
Damjan Pantic ◽  
Bratislav Matovic
Keyword(s):  
Comparative Analysis ◽  
Basal Area ◽  
Comprehensive Understanding ◽  
Beech Forests ◽  
Volume Increment ◽  
Mixed Origin ◽  
High Selection ◽  
Individual Trees ◽  
Stand Conditions

This paper presents the comparative analysis of stand state, productivity and silvicultural demands in beech stands of mixed origin, with a predominating percentage of trees of coppice origin, in different site and stand conditions, in the area of Cestobrodica and Straza. The main cruising elements were analyzed in three ecological units: Number of trees, basal area, volume, volume increment, mean stand diameters and height and the development of individual trees. The differences of the study ecological units, presented through the values of cruising elements and the phases of diameter, height and volume development of individual trees, are computed by the analysis of variance and LSD test. The analysis and the concluded significant differences enabled the real and comprehensive understanding of the state of these stands, based on which the long-term objectives of forest management were decided (conversion into a high silvicultural form) and actual silvicultural demands and measures - high selection thinning.

Effects of Crown Thinning on Baldcypress Height, Diameter, and Volume Growth

1988 ◽  
Vol 12 (4) ◽  
pp. 252-256 ◽  
Author(s):  
Stephen G. Dicke ◽  
John R. Toliver
Keyword(s):  
Volume Growth ◽  
Basal Area ◽  
Height Growth ◽  
Taxodium Distichum ◽  
Volume Increment ◽  
Crown Thinning ◽  
Epicormic Branching

Abstract Crown thinning a 63-year-old stand of baldcypress (Taxodium distichum [L.] Rich.) averaging 220 ft²/ac of basal area to 180, 140, and 100 ft²/ac resulted in 5-year diameter growths of 0.44, 0.51, and 0.77 in., respectively. The unthinned control was significantly less at 0.31 in. Six-year height growth averaged 3.1 ft and was not influenced by treatment. Thinning to 140 and 100 ft²/ac stimulated epicormic branching on many trees, which may lower log quality. All crown thinning treatments appeared to increase sawtimber volume increment and sawtimber volume/ac over the control 5 years after thinning. South. J. Appl. For. 12(4):252-256.

scholarly journals The Difficulty of Predicting Eastern Spruce Dwarf Mistletoe in Lowland Black Spruce: Model Benchmarking in Northern Minnesota, USA

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 843
Author(s):  
Ella R. Gray ◽  
Matthew B. Russell ◽  
Marcella A. Windmuller-Campione
Keyword(s):  
Stand Structure ◽  
Black Spruce ◽  
Forest Health ◽  
Basal Area ◽  
Predictive Performance ◽  
Stand Age ◽  
Management Decisions ◽  
Dwarf Mistletoe ◽  
Growing Seasons ◽  
Model Interpretation

Insects, fungi, and diseases play an important role in forest stand development and subsequently, forest management decisions and treatments. As these disturbance agents commonly occur within and across landscapes, modeling has often been used to inform forest planning and management decisions. However, models are rarely benchmarked, leaving questions about their utility. Here, we assessed the predictive performance of a Bayesian hierarchical model through on–the-ground sampling to explore what features of stand structure or composition may be important factors related to eastern spruce dwarf mistletoe (Arceuthobium pusillum Peck) presence in lowland black spruce (Picea mariana (Mill.) B. S. P.). Twenty-five state-owned stands included in the predictive model were sampled during the 2019 and 2020 growing seasons. Within each stand, data related to the presence of eastern spruce dwarf mistletoe, stand structure, and species composition were collected. The model accurately predicted eastern spruce dwarf mistletoe occurrence for 13 of the 25 stands. The amount of living and dead black spruce basal area differed significantly based on model prediction and observed infestation, but trees per hectare, total living basal area, diameter at breast height, stand age, and species richness were not significantly different. Our results highlight the benefits of model benchmarking to improve model interpretation as well as to inform our understanding of forest health problems across diverse stand conditions.

Experience with the production of goods with the state quality sign

1974 ◽  
Vol 31 (9) ◽  
pp. 608-610
Author(s):  
T. A. Pashkova
Keyword(s):  
The State ◽  
State Quality

Modèle de prédiction des essences feuillues et résineuses du Québec

1982 ◽  
Vol 12 (2) ◽  
pp. 232-239 ◽  
Author(s):  
Chhun-Huor Ung ◽  
Jean Beaulieu ◽  
Daniel Demers
Keyword(s):  
Prediction Model ◽  
Basal Area ◽  
Growth Conditions ◽  
The State ◽  
Department Of Energy ◽  
Forest Species ◽  
Permanent Sample Plots ◽  
Real Growth ◽  
Basic Characteristics ◽  
Softwood Species

This paper describes a prediction model adopted by the Department of Energy and Resources of Quebec to (i) update temporary sample plots and (ii) project into the future the state of permanent sample plots in Quebec forests. Predicting the growth of a forest species means predicting the state of this species in time. Three basic characteristics mark the state of a species in a given year: number of trees, their total basal area, and their total volume. To date, in Quebec, normal or empirical yield tables have been used to predict the state of some species in ideal or real growth conditions, but these yield tables apply only to pure or almost pure even-aged stands. The prediction model for hardwood and softwood species presented in this paper serves the same purpose as the yield tables; however, it differs from the yield tables in that it can predict the state of each hardwood or softwood species found in pure or mixed, even- or uneven-aged stands. The prediction model was validated for 19 species found in a pilot territory located in the Basse-Gatincau (southwestern Quebec). The paper terminates with a discussion on the limitation of the prediction model and the conditions for its use.

Tekstura drzewostanów naturalnych w polskich parkach narodowych na tle teorii dynamiki lasu

2021 ◽  
Author(s):  
Leszek Bartkowicz ◽  
Keyword(s):  
Tree Species ◽  
Stand Structure ◽  
Basal Area ◽  
Site Conditions ◽  
Gap Dynamics ◽  
Old Growth ◽  
Mosaic Pattern ◽  
Spruce Forests ◽  
Old Growth Forest ◽  
Patch Mosaic

The aim of the study was to compare a patch-mosaic pattern in the old-growth forest stands developed in various climate and soil conditions occurring in different regions of Poland. Based on the assumption, that the patch-mosaic pattern in the forest reflect the dynamic processes taking place in it, and that each type of forest ecosystem is characterized by a specific regime of natural disturbances, the following hypotheses were formulated: (i) the patches with a complex structure in stands composed of latesuccessional, shade-tolerant tree species are more common than those composed of early-successional, light-demanding ones, (ii) the patch-mosaic pattern is more heterogeneous in optimal forest site conditions than in extreme ones, (iii) in similar site conditions differentiation of the stand structure in distinguished patches is determined by the successional status of the tree species forming a given patch, (iv) the successional trends leading to changes of species composition foster diversification of the patch structure, (v) differentiation of the stand structure is negatively related to their local basal area, especially in patches with a high level of its accumulation. Among the best-preserved old-growth forest remaining under strict protection in the Polish national parks, nineteen research plots of around 10 ha each were selected. In each plot, a grid (50 × 50 m) of circular sample subplots (with radius 12,62 m) was established. In the sample subplots, species and diameter at breast height of living trees (dbh ≥ 7 cm) were determined. Subsequently, for each sample subplot, several numerical indices were calculated: local basal area (G), dbh structure differentiation index (STR), climax index (CL) and successional index (MS). Statistical tests of Kruskal- Wallis, Levene and Generalized Additive Models (GAM) were used to verify the hypotheses. All examined forests were characterized by a large diversity of stand structure. A particularly high frequency of highly differentiated patches (STR > 0,6) was recorded in the alder swamp forest. The patch mosaic in the examined plots was different – apart from the stands with a strongly pronounced mosaic character (especially subalpine spruce forests), there were also stands with high spatial homogeneity (mainly fir forests). The stand structure in the distinguished patches was generally poorly related to the other studied features. Consequently, all hypotheses were rejected. These results indicate a very complex, mixed pattern of forest natural dynamics regardless of site conditions. In beech forests and lowland multi-species deciduous forests, small-scale disturbances of the gap dynamics type dominate, which are overlapped with less frequent medium-scale disturbances. In more difficult site conditions, large-scale catastrophic disturbances, which occasionally appear in communities formed under the influence of gap dynamics (mainly spruce forests) or cohort dynamics (mainly pine forests), gain importance.

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