Allowable Cut Research Articles

Clear-cutting of temperate forests in late successional stages triggers successional setbacks extending compositional recovery by an additional century

Clear-cutting is used by foresters worldwide to harvest timber from forest ecosystems. Clear-cutting of cool–wet boreal forests in late successional stages can maintain successional trajectories pointed toward the composition of a late successional stages. However, clear-cutting of warm–dry boreal forests in late successional stages can trigger reversion of successional trajectories back toward forests of earlier stages because early-successional shade-intolerant species are more abundant than in cool–wet boreal forests, a process that is referred to as a successional setback. Such successional setbacks can generate sustainability issues by extending the expected time to compositional recovery after clear-cutting. This can lead to an overestimation of allowable cuts of economically important late-successional species and subsequently to a temporary forest composition conversion if the occurrence of successional setbacks remains unassessed. Temperate forests in late successional stages are warmer and drier than boreal forests and consequently include more early-successional shade-intolerant species susceptible to encroach clear-cut areas. Even if current ecological knowledge suggests that temperate forests could be susceptible to post-clearcut successional setbacks, a comprehensive assessment has yet to be undertaken. The objective of the present study was to assess whether clear-cutting has triggered successional setbacks in temperate forests. Therefore, we studied post-clearcut successional trajectories by using forest inventory data covering the entire temperate forest of the province of Québec, eastern Canada (209 000 km2). Clear-cutting triggered successional setbacks in both ecological regions forming the temperate forest. After clear-cutting, successional trajectories of trees pointed toward the composition of an early successional stage. To address this sustainable management issue in a comprehensive manner with clear-cutting, foresters could use partial cut approaches.

Carbon Sequestration Through Forestry: A Differential Equation Approach

Carbon sequestration through forestry represents a promising approach to partially counteract anthropogenic greenhouse gas emissions driving climate change. Tree growth naturally removes carbon dioxide from the atmosphere, storing it as biomass. Sustainably managed forests can effectively function as carbon sinks. However, determining optimal forestry policies involves balancing complex ecological dynamics with economic constraints. This study develops differential equation models quantitatively capturing forest growth, timber harvesting, and carbon sequestration dynamics. Logistic models are first adapted to simulate biomass accumulation of representative tree species. Lifecycle growth patterns spanning juvenile to mature phases are incorporated, along with climate effects. Biomass levels are proportionally related to carbon dioxide removal rates from the atmosphere. Deforestation impacts are analyzed by incorporating harvesting-induced biomass reductions. Sustainability constraints are implemented to ensure minimum viable tree densities across harvest rotations. Optimization techniques then identify management guidelines maximizing economic returns given ecological stability considerations. The goal is providing quantitative insights into rotation lengths, planting densities, and allowable cuts upholding both climate change mitigation and commercial demands. Findings can inform science-based forestry policies to leverage forests as sustainable natural carbon sinks.

Лесоэксплуатационное районирование лесных субарктических территорий

The purpose of this study is to classify the territories of the forest fund of the Republic of Karelia and Murmansk region at the level of central forestries on the basis of multifactorial assessment of timber resources, natural and production conditions, and road infrastructure. Forest exploitation zoning was carried out taking into account 20 variables. For this purpose, factor and hierarchical cluster analysis, k-means method and discriminant analysis were successively applied. Based on statistical methods, all central forestries were distributed into 9 clusters: 4 large clusters (No. 2, 3, 8, 9), including several forestries, and 5 (No. 1, 4–7), each formed by one forestry. Forestries of cluster No. 2 had large annual allowable cut (AAC), significant average forest reserve per hectare and hardwood reserve. Forestries of cluster No. 3 were characterized by small AAC and forest reserves per hectare. Cluster No. 8 forestries were characterized by average AAC and forest stock per hectare, high proportion of forests in stagnant moisture conditions. Forestries of cluster No. 9 were intermediate in their characteristics between the forestries of clusters No. 2 and No. 8. The forestry of cluster No. 1 is close to the forestry of cluster No. 2 in its characteristics, but its forests are more productive. Forestries of small clusters No. 4, 6, 7 have the highest forest stock per hectare. Differences in some variables did not allow them to be combined into one cluster. The forestry of cluster No. 5 is similar in terms of natural and production conditions to the forestry of cluster No. 3 but had a small estimated harvesting area for the coniferous component. The results of the study can be considered when solving the issues of organization and development of forestry and forest industry complex in the Republic of Karelia and Murmansk region. For citation: Budnik P.V., Baklagin V.N., Galaktionov O.N. Forest Exploitation Zoning of Forest Subarctic Territories. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 6, pp. 114–135. (In Russ.). https://doi.org/10.37482/0536-1036-023-6-114-135

Forest activities drive diversity and structure in the tropical rainforest

AbstractLogging is widely known to be one of the major drivers of the loss of timber resources in tropical rainforests. In order to assess the contribution of this activity to biodiversity and carbon storage in Cameroon's Forest Management Units, this study was carried out in three Annual Allowable Cuts (AAC), of which two were logged, AAC 1‐1 (logged two years before), AAC 1‐2 (logged one year before) and one unlogged (AAC 1‐4). On each stand, 100 sampling plots of 20 m × 20 m were laid. The plot survey assessed the diversity indices, basal area, Aboveground Biomass, wood density, total height and importance value index of the tree species having ≥10 cm diameter at breast height. A total of 203 species belonging to 158 genera and 58 families were recorded. Piptadeniastrum africanum (7.21), Sterculia rhinopetala (23.35) and Ceiba pentandra (14.5) were the commonly traded species with the highest importance value index, respectively, for AAC 1‐1, 1‐2, and 1‐4. Non‐symmetric correspondence analysis (NSCA) revealed that the plots in AAC 1‐4 are more diverse, containing more biomass than those in AAC 1‐1 and 1‐2. Although selective logging has reduced species richness, it remains important to develop enrichment of species removed for ecosystem restoration.

Intensive management increases flexibility in managing wood supply

We modelled the potential impact of intensification of plantation management and thinning, on timber supply of an ∼500 000 ha forest in Alberta, Canada over a 200-year planning horizon. Pre-commercial and commercial thinning were applied to a portion of the better sites, which allowed shortening of the time to merchantability and earlier harvest than unthinned stands; less than 25% of the forest was thinned over the course of the plan. The sustainable harvest rate, represented here as the annual allowable cut (AAC), increased by ∼14% above baseline, when thinning was applied. Similarly, there was a 20.7% increase in AAC projected with the relaxation of even flow rules if thinning was also applied. Finally, thinning offset the expected decline in AAC after a 20-year surge in cutting of mature pine, designed to slow an epidemic of mountain pine beetle. In terms of wood supply, the volume extracted at thinning was <2% of annual supply but volume from final harvest from thinned stands, at times, surpassed that of unthinned stands of the forest. Individual tree size from thinned stands was ∼twice that from unthinned areas in the second part of the planning period, offsetting the expected decline in piece size after the era of harvest of natural forests.

Effect of Moisture Content and Preservatives on the Discoloration of Oil Palm (Elaeis guineensis Jacq.) Lumber

Considering the current rate of expansion of the lumber processing industry in the world, the current annual allowable cut of one million cubic meters of round logs is considered to be insufficient to satisfy the increasing demand of timber industries. One major area that has been highlighted in the forest policy is the introduction of lesser-used species to widen the natural resource base of the forest and to address the imbalance between supply and demand for the resources. As a contribution to addressing this problem, oil palm lumber, a lesser-used species, was subjected to different moisture content variations to determine its behavior with respect to discoloration. Specimens of oil palm trunks were extracted at Norpalm Oil Mill in the Western Region of Ghana. Oil palm lumber specimens were conditioned in a kiln to a moisture content of 15%, 20%, 25%, 30%, 40%, and 50%. The results obtained covered discoloration and mold. The effect of the extractives on the discoloration of oil palm lumber was also investigated by means of immersing some samples of oil palm lumber into sea water and tap water for 48 h. Although Dursban 4E is a widely used preservative in the timber industry, oil palm lumber specimens of 40 mm thick immersed in Dursban 4E for 48 h and conditioned in a kiln to a moisture content of 30% were discolored from week 2. However, oil palm lumber specimens of 40 mm thick that were immersed in tap water for 48 h, and thereafter immersed in Dursban 4E for another 48 h, then kiln dried to a moisture content of 15%, 20%, 25%, and 30%, did not show any discoloration from week 2 to week 18. It was discovered that in the utilization of oil palm lumber, it should be immersed in tap water for 48 h before any chemical treatment is given, and thereafter kiln dried. From the general results, the species proved to be good substitute for some of the ‘noble’ species that are going extinct from the forests of Ghana.

Projection Matrix Models: A Suitable Approach for Predicting Sustainable Growth in Uneven-Aged and Mixed Hyrcanian Forests

The Hyrcanian forests of Iran are mainly managed with the single-selection silvicultural technique. Despite significant ecological benefits associated with selection cutting, this type of forest management leads towards more challenging situations where it is difficult to maintain and practice successful forestry than in even-aged systems. Therefore, this study provides relevant management tools in the form of models to estimate low growth levels in Hyrcanian forests. In the present study, estimation of the population growth rate and then the allowable cut rate of these forests using a matrix model have been calculated in the Gorazbon district. For this purpose, the data of 256 permanent sample plots measured during the years between 2003 and 2012, as well as the data recorded about the trees harvested according to the forestry plan, have been used. As a first step, the most frequently occurring tree species were divided into four groups (beech, hornbeam, chestnut-leaved oak, and other species). Compartments of the district were divided into two groups of logged and unlogged compartments. The purpose of this division was to estimate the allowable cut and compare its volume with the volumes of observed and predicted allowable cuts obtained from forestry plans. The results showed that the total operated allowable cut (OAC) in logged compartments was more than the estimated allowable cut (EAC). In unlogged compartments, the total predicted allowable cut (PAC) was more than EAC. A comparison of EAC and OAC showed that hornbeam has been harvested more than its potential. However, chestnut-leaved oak and other species group have depicted opposite trends. Our models provide important advancements for estimating allowable cut that can enhance the goal of practicing sustainable forestry.

Introducing a New Approach in Stand Tending Planning and Thinning Block Designation by Using Mixed Integer Goal Programming

Long-term management plans have been developed for nearly all of the forests in Turkey. These plans are applied at a sub-district management unit level and may contain guidance for both intermediate yield and final yield harvests. To implement an intermediate yield plan, which involves the scheduling of forest thinnings (stand tending), consideration in Turkey is given to the advantages of working in the same terrain and the same general area each year. Therefore, compartments are often clumped together to create thinning blocks, taking into consideration the thinning priority of the stands, road conditions, site index, age, and proximity of the compartments. Further, when preparing annual budgets and planning to meet the market’s needs, forest enterprises require an even flow of intermediate wood volume each year. In this paper, we introduce a new approach in stand tending planning designed to schedule an equal amount of intermediate wood volume each year and to create thinning blocks by minimizing the distance to pre-defined ramps (landings). We developed both linear and nonlinear goal programming models to minimize both the deviations from a harvest volume (annual intermediate yield allowable cut) target and the deviations from a target value determined for the distances (total and average) of the centroid of each compartment to the hypothetical forest ramps. By using the extended version of Lingo 16, we solved the problem with different weights for the deviations in volume and distance that ranged from 0.0 to 1.0, in 10% intervals, which created 11 scenarios. We carefully analyzed the results of each scenario by taking into consideration the wood volume and distance of compartments to the ramps. The best scenario using the linear model produced a deviation in volume scheduled for the entire decade of 6 m3, while the deviation in total distance between harvest areas and ramps was 59.7 km. Scenario 5, with weights of 0.6 for volume and 0.4 for distance, produced these results, where compartments were closest to one another. The best scenario using the nonlinear model also produced a deviation in volume of 0 m3 and the total average deviation in distance between harvest areas and ramps was 8.7 km. Scenario 3, with weights of 0.8 for volume and 0.2 for distance, produced these results. The approach and models described through this study may be appropriate for further integration into forest management planning processes developed for the planning of Mediterranean forests.

СОВРЕМЕННАЯ ДИНАМИКА ЛЕСОПОЛЬЗОВАНИЯ В БОРЕАЛЬНЫХ ЛЕСАХ РОССИИ (НА ПРИМЕРЕ АРХАНГЕЛЬСКОЙ ОБЛАСТИ)

The article examines the dynamics of forest management in the Arkhangelsk region for the period from 2008 to 2020. Over the past three years, about 44 million m3 of marketable timber has been cut (57.6% of the permissible harvest). The withdrawal of marketable timber (within the allowable cut) increased by almost 1.5 times (from 10.24 to 14.86 million m3). The maximum volume of harvested wood falls on 2018 and 2020, respectively. The share of soft-leaved wood cut down during the period under review increased from 19.1% to 31.1%. This increase is due to the transport accessibility of secondary deciduous plantations located in close proximity to logging roads. The average share of marketable timber harvested by non-clear felling was 14.4%, the maximum volume of timber harvested by these fellings was recorded in 2020 - 2.6 million m3 or 17.4%. The total area involved in economic activities increased by 38.5%, from 100.8 thousand hectares to 138.9 thousand hectares. On average, 22.6% was allotted for partial cutting, and 77.4% for clear cutting. Spatial analysis of partial cuttings in the total volume of timber harvesting showed a very low percentage (up to 10%) in 14 forestries. This is due to the logging of the last century, the structure of the forest fund, the presence of wet and swampy areas, the lack of road infrastructure, etc. The distribution of forestries by the intensity of forest use showed that a high intensity of harvesting of marketable timber (over 500.1 thousand m3) is observed in 13 forest districts, mainly concentrated in the south of the Arkhangelsk region. The dynamics of the forest fund testifies that modern forest management has made adjustments to the distribution of the areas of forest plantations in the context of age groups and household sections. For example, the area of coniferous forests decreased by 649.2 thousand hectares (3.8%), while the area of soft-leaved forests increased by 471.95 thousand hectares or 9.1%. Past and modern forest management is reflected in the age structure of forests. A very small percentage of ripening stands in the future will not make it possible to compensate for the felled ripe and overmature stands at their expense. It is possible to level the age structure of the forest fund and form a so-called continuous forest taking into account the current trends in forest management, when on average about 60% of periodic yield is cut down

Towards sustainable forestry: Using a spatial Bayesian belief network to quantify trade-offs among forest-related ecosystem services

Assessing trade-offs among ecosystem services (ESs) that are provided by forests is necessary to support decision-making and to minimize negative effects of timber harvesting. In this study, we examined how spatial data, forest operational rules, ESs, and probabilistic statistics can be combined into a practical tool for trade-off analysis that could guide decision-making towards sustainable forestry. Our main goal was to analyze trade-offs among the wood provisioning ES and other forest ESs at the landscape level using a Bayesian belief network (BBN). We used LiDAR data to derive four ES layers as inputs to a spatial BBN: (i) wood provisioning; (ii) erosion regulating; (iii) climate regulating; and (iv) habitat supporting. We quantified operational constraints with four forest operational rules (FOR) that were defined in terms of: (i) potential harvest block size; (ii) distance between a small potential harvest block and a larger harvest block; (iii) gross merchantable volume (GMV); and (iv) distance to an existing resource road. Maps of the most probable trade-off classes between the wood provisioning ES and other ESs enabled us to identify areas where timber harvesting should be avoided or where timber harvesting should have a very low negative effect on other ESs. Even with our most restrictive management scenario, the total GMV that could be harvested met the annual allowable cut (AAC) volume required to meet sustainable forestry objectives. Through our study, we demonstrated that high-resolution spatial data could be used to quantify trade-offs among wood provisioning ES and other forest-related ESs and to simulate small changes in ES indicators within the BBN. We also demonstrated the potential to evaluate management scenarios to reduce trade-offs by considering FOR as inputs to the BBN. Maps of the most probable trade-off classes among two or three ESs under operational constraints provide key information to guide forest management decision-making towards sustainable forestry.

Real option valuation of timber harvesting contracts

AbstractA primary challenge for forestry businesses is valuing timber harvesting contracts. This article presents an empirical application of determining the optimal harvest volumes under stochastic prices to determine the economic value of timber harvesting contracts and manage business risk using real options theory. We illustrate a dynamic optimization solution procedure and the choice between a single long‐term versus two short‐term timber harvesting contracts from a risk management perspective. A case study of timber harvesting contracts sold in British Columbia is used to demonstrate specification of the many details and adaptations that are required in such valuation problems. Our article offers some interesting results. The highest timber harvesting contract values occur with optimal harvest quantities rather than an equal annual allowable cut (AAC). The difference in values can be substantial (two to three‐fold). Consequently, forestry businesses can benefit by timing their harvest to nonequal quantities in later years of a timber harvesting contract. Depending on the quality of timber, the maximum stumpage value for the second short‐term timber harvesting contract ranges from $12 to $17.8 per cubic meter, resulting in lower profit margins for equal AAC. In contrast, with optimal harvesting, the maximum stumpage value ranges from $2 to $8.5 per cubic meter and higher profit margins. These bounds for stumpage price and profit margins would be useful for forest businesses to better manage business risks when bidding for timber harvesting contracts.

Associate Editors/Corédacteurs

Moose (Alces alces L.) browsing in Gros Morne National Park has damaged its balsam fir (Abies balsamea (L.) Mill.)dominated forest. A forest estate model was used to evaluate (i) the impacts of moose browsing and woodcutting on forest succession and (ii) strategies of forest restoration through planting and moose population management. The simulation results show that under current heavy browsing pressure growing stock of balsam fir decreases by 38%, but the area of spruce (Picea mariana (Mill.) BSP and P. glauca (Moench) Voss) increases by 32% over a 100-year planning horizon, compared to that under light browsing scenario which is assumed to be similar to the forest outside the Park due to moose population management. Annual allowable cut (AAC) for the Park’s 19 400 ha domestic harvest area is estimated to be around 120 979 m3 in a light browsing scenario, 21% higher than the sustainable harvest level in a heavy browsing scenario. The model forecasts a 97% reforestation of the Park’s 7 194 ha disturbed area by planting in the heavy browsing scenario, leading to an increase in total forest growing stock by 22% and AAC by 12%. Integration of planting with moose population management could be a more efficient way of restoring forest under high browsing pressure in GMNP.

Intensive moose browsing and small-scale domestic woodcutting impacts on forest successional trajectories in Gros Morne National Park, Canada

Moose (Alces alces L.) browsing in Gros Morne National Park has damaged its balsam fir (Abies balsamea (L.) Mill.)-dominated forest. A forest estate model was used to evaluate (i) the impacts of moose browsing and woodcutting on forest succession and (ii) strategies of forest restoration through planting and moose population management. The simulation results show that under current heavy browsing pressure growing stock of balsam fir decreases by 38%, but the area of spruce (Picea mariana (Mill.) BSP and P. glauca (Moench) Voss) increases by 32% over a 100-year planning horizon, compared to that under light browsing scenario which is assumed to be similar to the forest outside the Park due to moose population management. Annual allowable cut (AAC) for the Park’s 19 400 ha domestic harvest area is estimated to be around 120 979 m3 in a light browsing scenario, 21% higher than the sustainable harvest level in a heavy browsing scenario. The model forecasts a 97% reforestation of the Park’s 7 194 ha disturbed area by planting in the heavy browsing scenario, leading to an increase in total forest growing stock by 22% and AAC by 12%. Integration of planting with moose population management could be a more efficient way of restoring forest under high browsing pressure in GMNP.

Economic impacts of partial harvesting: Mitigating mid-term timber supply shortages as a result of pest outbreaks

Natural disturbances such as pest outbreaks have a significant impact on forest dynamics and services, including the loss of mature stands. From a wood production perspective, these disturbances can lead to long-lasting imbalances in the overall age-class structure of the forest, potentially resulting in a shortage of mature harvestable stands. Researchers from Natural Resources Canada’s (NRCan) Canadian Forest Service (CFS) have made a timber supply analysis of the Dunière forest located in the centre of the Gaspé Peninsula (Québec). This region suffers from an age-class structure imbalance caused by an eastern spruce budworm (ESB) outbreak that ended in 1984, and is consequently facing a reduced annual allowable cut, leading to long- term implications for the regional forest sector. The authors suggest that partial harvesting – the removal of a proportion of timber in a mature stand several years before a final cut is carried out – is a promising opportunity in the ESB-affected area for mitigating mid-term timber supply shortages by smoothing the fibre supply over time.

Implementation of Sustainable Lumber Management Principles in Irkutsk Region

Forestry in Irkutsk region features very low efficiency of forest resource exploitation. This works aims to estimate the amount of forest resource in the region, its condition and accessibility. These three data are taken as basis for the method of allowable cut as one of the key forest management tools. The article analyzes the types of lumber in various areas of the region and the dynamics of their exploitation according to the territory zoning, and provides a feasibility assessment of allowable cut development. The statistic reports of the regional Ministry of Timber Complex are used as information resource for the estimated planned and actual lumber exploitation in the forestry areas in seven zones of Irkutsk region. The analysis has revealed an ambiguity in the input data for calculating indicators of standing timber development. According to the study, the input value for logging in some forestry areas is overestimated, which leads to faster forest resource depletion. The authors state that, in the context of increasing the efficiency of forestry, the target indicators of the Timber Complex Development Programme 2019–2024 in Irkutsk region need revision, and the lumber management system requires further improvement.

ИССЛЕДОВАНИЕ ПРОЦЕССА ОБРАЗОВАНИЯ КОЛЕИ И ЕЕ УСТОЙЧИВОСТИ ПРИ РАБОТЕ ЛЕСНЫХ МАШИН И ТРЕЛЕВОЧНЫХ СИСТЕМ НА СКЛОНАХ МАССИВА ОТТАИВАЮЩЕГО ПОЧВОГРУНТА

A significant part of mature and over-mature commercial forests of the Russian Federation are concentrated in the Far Eastern Federal District. Most of the forests of the Far East are characterized by a relief that is inconvenient for the operation of traditional machine systems for logging operations (steep and very steep slopes). In addition, a significant part of the forests of the Far East grows on permafrost. It is known that the forests on the slopes are among the most vulnerable from the ecological point of view, the same can be said about the forests on the permafrost. As a result, the permafrost forests growing on the slopes can be attributed to one of the most vulnerable forest ecosystems. In this regard, the requirements for the environmental efficiency of forest machines and skidding systems when harvesting wood in the forests of the permafrost zone growing on the slopes are one of the most stringent. This circumstance is very important, for example, for the development of logging in the Republic of Sakha (Yakutia). It is well known about the negative impact of forest machine propellers on the soils of cutting areas; this issue has been studied and is being studied by a large number of scientists. The negative impact on soils, first of all, consists in overconsolidation and the formation of a track, which in the future is the center of water and wind erosion. Solving the problem of ecological compatibility of modern forest machines and skidding systems with soils of permafrost cutting areas growing on the slopes will increase the effective development of the allowable cut in forests on permafrost. The most optimal way to increase the environmental compatibility of machines and forest ecosystem is to substantiate the optimal machine parameters and performance indicators for specific conditions

Norway spruce production and static stability in IUFRO thinning experiments in the Czech Republic

Despite recent issues, Norway spruce remains the most important commercial tree species which might be demanded henceforth for its broadly utilizable wood. Even before foresters faced both the bark beetle outbreaks and spruce decline, spruce monospecific stands were known to be prone also to other damage due to snow and wind. On this basis, measures that help prevent such failures were looked for, which resulted in the establishment of international IUFRO experimental series focused on impacts of different thinning regimes on stability and production of spruce stands. The thinning treatments differed in numbers of trees removed and retained on the site when dominant height of crop trees was reached or allowable cut in non-crop trees was accumulated. Also effects of different width of skid trails were tested. The study summarizes the results from the two IUFRO experiments in the Czech Republic. Effects of thinning regimes on spruce were found positive though thinning reduced the total volume production of wood while improving crop-tree stability which enhanced production safety. Different widths of skid trails had no effect on wood increment. Early thinning of spruce can be used to prevent their damage. No such measure, however, can alleviate the spruce decline.

Projecting future aboveground biomass and productivity of managed eastern Canadian mixedwood boreal forest in response to climate change

Eastern Canadian boreal forests are mainly influenced by natural wildfires and forest management activities. To evaluate forest dynamics under possible interactions among fire and timber harvest in a future climate warming scenario (RCP 2.6, RCP 4.5 and RCP 8.5) the forest landscape model Landis II was used to simulate the dynamics of the 78000 km2 of boreal forests in eastern Canada. Forest management intensity scenarios were modeled considering the changes in the annual harvested area (0.5%, 1%, and 2%) and the age that conifers and hardwoods can be harvested (50 and 30 years, 70 and 50 years, and 90 and 70 years). The results of the 300-year model projections implied that both forest management intensity and climatic scenarios explained most of the variability in aboveground biomass, aboveground net primary productivity and forest composition. Forest management seems to be the most important factor that modified the landscape in the southern forests because there were scheduled stands with the age and composition required by each harvesting prescription to deal with the annual allowable cut volume. On the contrary, in the northern forests there was a mixed effect of climate change and forest management because many of the areas suitable for harvesting were previously burned limiting the amount of area available for harvesting. Thus, although it is expected an increase in wildfire area burned due to climate change, the intensification of forest management seems to be the most important driver of the increase of hardwoods and mixed stands and the decrease of conifers stands on the mixedwood boreal landscape, mainly in the southern forests. These results suggest that timber supply would be at risk in the Abitibi Plain, therefore, some strategies should be applied to adapt forest management to climate change.

Assessing Wood Waste by Timber Industry as a Contributing Factor to Deforestation in Ghana

This study assesses the wood waste generation, its management practices, and its effects on the forests in Ghana. The rate of logging in Ghana has increased and this can be attributed to the increase in the establishment of Sawmilling companies in the country. Increased in the installation of sawmilling companies has increased the sawn timber production. The use of outmoded milling machines has led to an increase in waste generation. An increase in production has led to an increase in the annual allowable cut in the country, which has overrun the limit of sustainable forestry. A qualitative research method was employed for the research work. A well-structured questionnaire was administered to the study to solicit the views of the wood industries about wood waste generation and its management practices. The study population comprised of 50 sawmilling companies. From the data collected, it was observed that most of the timber production companies do not know how to manage the waste generated and the waste is left un-utilized. In general 80% of the timber production companies responded that they have an idea of wood waste management but do not have the technical know-how to manage the waste. It was observed that 80% of the timber production companies do not manage the waste they generate during their operations. Wood shavings, sawdust, wood slabs, offcuts, branches, and others are left un-utilized. From the observations made in the visited sawmills, chunks of waste are generated on the site. The fact that the wood which is un-utilized (waste) and the wood, which is utilized as sold products, are equal in cost to the company which highlights the poor material and cost-efficiency. Wood industry materials and cost efficiency, together with waste management practices and their contribution to deforestation in the country, are discussed.

Accuracy testing of Wolf von Wulfing stand table in estimating teak stand volume

The Wolf von Wulfing (WvW) stand table made in 1932 is commonly used to estimate the volume of teak stands at a certain class of site quality (bonita) and age. A state forest enterprise (Perum Perhutani) usually uses the WvW table to estimate the volume of stands at the end of the cutting cycle or in other words used to determine the annual allowable cut (AAC). The accuracy level of estimated stand volume using WvW table still needs to be tested. This study aims to test the accuracy of the Wolf von Wulfing stand table in estimating the volume of teak stands (Tectona grandis), using measurement results data on teak stands in the Forest Management Unit (FMU) of Ciamis (West Java) and Randublatung (Central Java). We conducted an analysis by comparing the stand volume using the WvW table with the stand volume obtained using the local volume table (TVL) that already available in each study location. Data analysis was performed using simple linear regression: Y = (30+|31X; X = Volume WvW; Y = Volume TVL. Regression analysis results showed that the relationship between Volume WvW (X) and Volume TVL (Y), expressed through the equation of Y = -2.83 + 0.88X, with the value of R2 adj=0.94. Hypothesis testing results on the value of (30 and (31, states that the value of (30=0 and (31^1, so that it can be concluded that the alleged results with the WvW table are overestimating. Alleged overestimate results can cause overcutting so that forest management is not sustainable.