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Highlights • Likelihood determinants for forest categories differ in different world regions. • Forest conditions, accessibility and environmental properties are important drivers. • Our final maps represent global patterns of forest classes and forest uses. • The maps visualize the current issues with available data. Abstract Forests provide numerous ecosystem services, such as timber yields, biodiversity protection and climate change mitigation. The type of management has an effect on the provision of these services. Often the demands for these services can lead to conflict – wood harvest can negatively impact biodiversity and climate change mitigation capacity. Although forest management differences are important, spatially explicit data is lacking, in particular on a global scale. We present here a first systematic approach which integrates existing data to map forest management globally through downscaling national and subnational forest data. In our forest management classification, we distinguished between two levels of forest management, with three categories each. Level 1 comprised primary, naturally regrown and planted forests. Level 2 distinguished between different forest uses. We gathered documented locations, where these forest categories were observed, from the literature and a database on ecological diversity. We then performed multinomial logit regression and estimated the effect of 21 socio-economic and bio-physical predictor variables on the occurrence of a forest category. Model results on significance and effect direction of predictor variables were in line with findings of previous studies. Soil and environmental properties, forest conditions and accessibility are important determinants of the occurrence of forest management types. Based on the model results, likelihood maps were calculated and used to spatially allocate national extents of level 1 and level 2 forest categories. When compared to previous studies, our maps showed higher agreement than random samples. Deviations between observed and predicted plantation locations were mostly below 10 km. Our map provides an estimation of global forest management patterns, enhancing previous methodologies and making the best use of data available. Next to having multiple applications, for example within global conservation planning or climate change mitigation analyses, it visualizes the currently available data on forest management on a global level. [ABSTRACT FROM AUTHOR]

Environmental and economic performance of forestry on drained peatlands was reviewed to consider whether continuous cover forestry (CCF) could be a feasible alternative to even-aged management (EM). CCF was regarded feasible particularly because continuously maintaining a tree stand with significant transpiration and interception capacity would decrease the need for ditch network maintenance. Managing CCF forests in such a way that the ground water levels are lower than in clear-cut EM forests but higher than in mature EM forests could decrease greenhouse gas emissions and negative water quality impacts caused both by anoxic redox reactions and oxidation and mineralization of deep peat layers. Regeneration studies indicated potential for satisfactory natural regeneration under CCF on drained peatlands. An economic advantage in CCF over EM is that fewer investments are needed to establish the forest stand and sustain its growth. Thus, even if the growth of trees in CCF forests were lower than in EM forests, CCF could at least in some peatland sites turn out to be a more profitable forest management regime. An advantage of CCF from the viewpoint of socially optimal forest management is that it plausibly reduces the negative externalities of management compared to EM. We propose that future research in drained peatland forests should focus on assessing the economic and environmental feasibility of CCF. [ABSTRACT FROM AUTHOR]

Plantation forestry is the ultimate alternative in reforesting degraded tropical ecosystems and in provisioning multiple ecosystem services beyond timber production. Therefore, we studied the management of Tectona grandis L.f. (teak) plantations in Costa Rica and simulated alternative management strategies incorporating simultaneously the values of carbon storage, biodiversity and timber production. Alternative management strategies included (1) extension of rotations, (2) reduced thinning and (3) conversion of even-aged to uneven-aged systems. Evaluation criteria were carbon storage in biomass, stand structural diversity as a proxy of biodiversity, and economic return from timber harvests. For growth predictions under future climatic conditions, we calibrated the hybrid forest growth model 3PG. We found that carbon storage could be increased by increasing rotation periods (e.g. +29.7% of carbon for a 50% increase in rotation length) and a no thinning management (+9.5% of carbon). For rotation extension associated economic losses were high (e.g. at 5% discount rate, the Land Expectation Value (LEV) decreased by 25.1% for a 50% extension of rotations). For thinning LEV increased with a low-thinning regime, but decreased with a no-thinning management (+9.5% and −23.6%, respectively). Payments for ecosystem services (PES) increased economic return by about 3–4%. Structural diversity increased by conversion to uneven-aged forest stands (Gini coefficients for basal area increased from 0.21 to 0.52). Economic returns from timber harvests were almost equal for even-aged and uneven-aged systems at 1% discount rate (max. −2% of LEV). At 5% discount rate, we observed economic losses of 11.1–20.1% compared to the even-aged scenario. At 10% discount rate, economic losses ranged between 43.6 and 104%. We concluded that extension of rotations and reduction of thinning intensity can be used as management strategies to increase the carbon storage of teak plantations. However, to compensate the associated economic losses through a PES scheme, payments for carbon sequestration need to be increased and special incentives for longer rotation periods and low thinning management need to be developed. The transformation into uneven-aged forest stands requires active investment at discount rates higher than 1%. Whether this investment can be offset by benefits from biodiversity and increased forest resilience is unknown and requires further investigations. Other measures of biodiversity conservation, such as the use of native and mixed tree species and the retention of old trees and deadwood are moreover necessary. [ABSTRACT FROM AUTHOR]

Mixed-species forests can have higher productivity, in terms of wood volume, than monospecific forests. In addition, higher tree species richness has been found to positively correlate with multiple ecosystem services and functions. Surprisingly, stem quality as one of the most important factors regarding the economic value of forests has rarely been formally studied in diverse forests. This paper aims at investigating how tree species richness influences stem quality and which factors may drive quality development in these stands. Stem quality, understood here essentially as the suitability of a particular stem for particular end-uses, is influenced by a tree's ability to capture sufficient resources for growth and is influenced by neighbouring trees, e.g. through shading and physical crown interactions. We collected data on crown size, stem form and tree health for over 12,000 trees in 209 study plots in six European regions (Finland, Germany, Poland, Romania, Italy and Spain) within naturally diverse forests to assess the impact of tree species richness on these characteristics. Results showed that quality variability between regions, stands and individual trees was high across species. At the stand level, there was a slight tendency towards lower stem quality with increasing diversity. However, individual trees of high quality were present at all diversity levels and for all target species. Tree species richness could not be confirmed as a primary influence on stem quality at the stand level. Rather, stand and individual tree properties such as structural composition, competition, tree size and crown characteristics were identified as the main factors for stem quality development, even in mixed stands. Many of the factors identified in this study can be directly or indirectly influenced by forest management strategies tailored to produce high-quality timber in mixed-species forests. Our findings suggest that diverse stands are not inferior regarding stem quality, while at the same time being able to provide various other ecosystem services . [ABSTRACT FROM AUTHOR]

Chilgoza pine ( Pinus gerardiana ) is an important source of income in forested eastern Afghanistan through the harvest of edible seeds. Since the late 1970s, the resource has been largely inaccessible to researchers and government personnel from outside the region, except for the years 2002–2015, roughly coinciding with Operation Enduring Freedom. We assessed physical and social attributes of chilgoza pine forests and the management capacity of indigenous communities. We employed interviews/questionnaires and field measurements performed by Afghan forest scientists from Kabul, trained local residents, and U.S. forest scientists associated with military operations to examine stakeholder perceptions of chilgoza pine forest resilience, assess forest health, stand structure and natural regeneration status. Intensive cone collection, tree damage caused by cone harvesting, grazing, fuelwood collection, and other biotic/abiotic factors (insects, diseases, and drought) were associated with chilgoza forest degradation. Most interviewees observed natural regeneration in the understory layer of chilgoza forest stands, but perceived the overall rate of natural regeneration to be insufficient. Respondents from villages prohibiting grazing and fuelwood collection reported the greatest regeneration while the converse was associated with the lowest levels of regeneration. Field measurements confirmed the scarcity of natural regeneration of chilgoza pine, portending the further decline of this species in Afghanistan. Field surveys indicated diverse stand conditions, age class structures and land use practices employed by local stakeholders, suggesting the need for situation-specific forest management recommendations. We discuss the opportunities and limitations for forest resources data collection in highly insecure environments. [ABSTRACT FROM AUTHOR]

Large-scale disturbances in forests are becoming more frequent due to a changing climate. Biotic disturbances can have cascading effects and therefore have a significant economic impact in forestry. It is therefore important to gain an understanding of the drivers of forest pest outbreaks in epidemic situations after large-scale disturbances and the implications for forest management. We investigated the influence of drivers on the bark beetle outbreaks following a large-scale ice storm in 2014 in Slovenia. A country-wide survey was done on the variables affecting ice storm damage to spruce trees. Additionally, the influence of the drivers of bark beetle attacks on outbreak intensity was assessed and compared under epidemic and endemic situations, and the effectiveness of forest management measures was assessed. Spruce trees were either uprooted or snapped, or the crown was lightly to severely damaged. The outbreaks under endemic situations were potentiated by the increasing amount of spruce and reduced by increasing slope. After the ice storm, the amount of sanitary felling because of outbreaks increased in areas with more steeper slopes, where the ice storm took place. An increase in the level of disturbance and a higher availability of dead and weakened trees positively affected bark beetle populations. The removal of dead trees alone in the first year after the ice storm was found to be an insufficient measure for preventing bark beetle outbreaks. The ineffectiveness of current practices suggests that bark beetle management should be reconsidered with regard to large-scale disturbances. When defining measures against bark beetle outbreaks, drivers in epidemic situations should be prioritized over those that are important in endemic situations. The results imply that the known factors that affect bark beetle attacks are not necessarily the same as those that drive bark beetle attacks after extraordinary disturbance events. Mixed stands should be promoted in forests for sustainable management. [ABSTRACT FROM AUTHOR]

Fungal fruit-bodies are an important economic resource both for recreational pickers and commercial markets. The broad interest in forest fungi and mushrooms has motivated attempts to develop appropriate silvicultural methods able to preserve and improve mushroom yields. Defining best practices for the sustainability and profitability of forest fungal resources is the main aim of ‘mycosilviculture’. However, the difficulty of monitoring and studying such a cryptic kingdom (i.e., fungi) under real forest conditions has led to rather scattered scientific knowledge of the effects of forest management regimes and silvicultural operations on wild mushroom resources. Here, we review the current scientific literature regarding the influence of (i) stand characteristics, i.e. stand age, stand density, canopy cover and tree species composition, (ii) silvicultural practices and (iii) other management-related disturbances affecting the yield of wild epigeous mushrooms, with the aim of systematizing existing scientific knowledge and identifying gaps in knowledge in order to suggest future lines of research. Most of the research in the field of mycosilviculture to date has focused on ectomycorrhizal mushrooms, which include the majority of wild commercial mushrooms. The main findings from the literature indicate that forest management practices, by modifying stand characteristics and microclimatic conditions, can influence wild mushroom occurrence and productivity, both positively and negatively, depending on the specific fungal ecological needs, reproductive strategies, forest type and management regime. Further research efforts relating to all aspects of the interaction between forest management, fungal ecology and mushroom production are needed: in particular, additional research efforts should be devoted to understanding mushroom yield dynamics in uneven-aged and mixed forests and evaluating the effects of regeneration methods on fungal communities. [ABSTRACT FROM AUTHOR]

In the period 1980s–2010s, 95% of wildfires in Mediterranean Europe were due to human causes. In this highly populated region, socio-economic changes occurred in the last decades have influenced wildfire activity. Socio-economic drivers are difficult to model at regional/global scales due to lack of spatial and temporal homogeneous data sources. In this paper, human caused-wildfires have been modeled using Land Use-Land Cover (LULC) interfaces based on the theoretical relationships found in previous works between human activities associated to this areas and fire occurrence. Generalized Additive Models were used to analyze human-caused fire occurrence in the European Mediterranean (EUMed) basin (Portugal, Spain, South-France and Italy) in two different time periods 1990s and 2000s. The estimated effects of the LULC interfaces on fire occurrence were significant in all periods in the whole study area and at country level, except in Portugal. Concerning trends, no significant changes were observed between periods in EUMed and in the individual countries. Nevertheless influence of the LULC interfaces on wildfire occurrence exhibited different tendencies among the studied sites. [ABSTRACT FROM AUTHOR]

On the San Carlos Apache Reservation in east-central Arizona, U.S.A., vegetation types such as ponderosa pine forests, pinyon-juniper woodlands, and grasslands have significant ecological, cultural, and economic value for the Tribe. This value extends beyond the tribal lands and across the Western United States. Vegetation across the Southwestern United States is susceptible to drought conditions and fluctuating water availability. Remotely sensed vegetation indices can be used to measure and monitor spatial and temporal vegetative response to fluctuating water availability conditions. We used the Moderate Resolution Imaging Spectroradiometer (MODIS)-derived Modified Soil Adjusted Vegetation Index II (MSAVI 2 ) to measure the condition of three dominant vegetation types (ponderosa pine forest, woodland, and grassland) in response to two fluctuating environmental variables: precipitation and the Standardized Precipitation Evapotranspiration Index (SPEI). The study period covered 2002 through 2014 and focused on a region within the San Carlos Apache Reservation. We determined that grassland and woodland had a similar moderate to strong, year-round, positive relationship with precipitation as well as with summer SPEI. This suggests that these vegetation types respond negatively to drought conditions and are more susceptible to initial precipitation deficits. Ponderosa pine forest had a comparatively weaker relationship with monthly precipitation and summer SPEI, indicating that it is more buffered against short-term drought conditions. This research highlights the response of multiple, dominant vegetation types to seasonal and inter-annual water availability. This research demonstrates that multi-temporal remote sensing imagery can be an effective tool for the large scale detection of vegetation response to adverse impacts from climate change and support potential management practices such as increased monitoring and management of drought-affected areas. Different vegetation types displayed various responses to water availability, further highlighting the need for individual management plans for forest and woodland, especially considering the projected drier conditions in the Southwest U.S. and other arid or semi-arid regions around the world. [ABSTRACT FROM AUTHOR]

Wind damage causes significant economic losses in boreal forests and elsewhere. Climate change may increase the occurrence of strong storms and decrease tree anchorage, making wind risk management an important aspect of future forest management. This study modeled the probability of wind throw as a function of thinning type, time since previous cutting, characteristics of the subject tree and stand, and shelter provided by adjacent upwind stands. The data were collected from two long-term silvicultural experiments, which experienced strong storm events during the past few years. The analyses showed that the most risky cutting was shelterwood cut, followed by even-aged silviculture characterized by repeated low thinnings. Cuttings where the probability of wind throw was lowest were selective high thinnings of uneven-sized stands, and dimension cutting. Very dense un-thinned stands had very low probability of wind damage. Increasing tree size, increasing height/diameter ratio, decreasing stand basal area, and decreasing basal area of adjacent upwind stands increased the probability of wind throw. Stands were most vulnerable to wind damage immediately after thinning. Uneven-sized stand structure was associated with low probability of wind throw. It was concluded that continuous cover management decreases wind damage, as compared to even-aged management. [ABSTRACT FROM AUTHOR]

Structural diversity of forests is important for biodiversity. In managed forests, structural diversity can be maintained by retaining living and dead trees, and by creating dead wood during logging operations. In Sweden, a small percentage of the trees is currently retained on each clear-cut. Since retention decreases revenues from forest harvesting, it is important to understand the consequences of retention for both forestry economy and biodiversity conservation. Thus, in this study we compared effects of retaining percentages ranging from 5% to 50% of the initial number of trees in 12 Scots pine-dominated stands in central Sweden. The retained trees in each stand consisted of equal proportions of green living trees, felled trees, high-cut trees and girdled trees. We estimated costs associated with tree retention and, as indicators of biodiversity conservation values, dead wood volumes, number of dead wood types, and dead wood diversity. We also estimated the damage caused by the logging operations on old dead wood. Revenue declined with increases in retention level, due mainly to associated reductions in harvested volumes, but partly to increases in logging costs. Both harvester and forwarder performance were lower at high than at low retention levels. The volume of dead wood increased with increases in retention level, since the number of retained trees killed per stand was proportional to the retention level. The number of dead wood types and dead wood diversity increased continuously up to the highest retention level of almost 50%. Moreover, old dead wood that was deemed particularly valuable for biodiversity was not destroyed at retention levels above 30%. In conclusion, dead wood destruction decreased with increasing retention level and costs increased proportionally to the retained volume. There were no signs of saturation of dead wood diversity as retention level increased. Therefore, mainly economic restrains will determine the retention level. [ABSTRACT FROM AUTHOR]

Gap-oriented forestry is a subject that is gaining interest worldwide as a compromise between economic and operational requirements on the one hand and environmental and safety concerns on the other. In principle, the approach mimics the effects of fine-scale natural disturbance while avoiding the threats of soil degradation and instability associated with large clearcuts, but at the same time, it does not limit the productivity associated with single-tree selection. Despite this interest, studies of the real effects of gap-oriented forestry are still limited, particularly those dealing with its impact on slope stability. This paper provides quantitative results about the slope stability of two mixed-conifer stands subjected to gap management in the Italian Central Alps that were monitored for five years after felling. The results showed that root decay, both in strength and density, further reduces additional root cohesion by approximately 60% in the first two years after felling and by another 20% in the third year; it completely vanishes by the fifth year. The observed reduction in root reinforcement values has dramatic consequences for slope stability. In fact: – In undisturbed conditions, the contribution of forest root systems guarantees a very low probability of instability (approximately 10% for a factor of safety of less than 1 as well as for steep slopes and high levels of saturation). – After only two years, the probability of instability dramatically increases for gentle slopes and low levels of saturation. We estimated a 50% probability of a factor of safety less than 1 when steepness was greater than 36–38° and soil saturation was 25% and when steepness was greater than 24–26° and soil saturation was 75%. – The probability of instability is highest five years after felling when the contribution of the root system has vanished. The probability of failure exceeded 50% when steepness was greater than 25–28° and saturation was 25%, and the slopes were practically unstable when saturation was 75%. – At the point when the contribution of the root system to slope stability was null, the regeneration process was still too undeveloped to contribute to soil reinforcement in any way. These results suggest that although the gap-oriented approach is, in principle, more conservative than large clearcuts, the pace of natural regeneration could be slower than the process of root decay, so instability could occur, especially where local slopes exceed 25° and soils are frequently saturated. [ABSTRACT FROM AUTHOR]

The southeastern United States is among the most productive forested areas in the world. Four endemic southern pine species – loblolly, longleaf, shortleaf, and slash – contribute significantly to the economic and ecological values in the region. A recently described phenomenon known as Southern Pine Decline (SPD) has been reported as having widespread impact in the southern pine region, particularly on loblolly pine. Root-feeding weevils and their associated fungi have been suggested as causal agents, even though literature and empirical research suggests that they are secondary insects colonizing weakened trees. Further, no published information exists about whether their associated fungi can cause mortality of mature trees in the southeastern U.S. Since there are significant management implications for pine health, we reviewed and critically examined the SPD phenomena on the southern landscape. Our regional analyses of USDA Forest Inventory and Analysis data show no discernable patterns related to pine growth or mortality, especially as related to topographic factors. There are no large-scale patterns related to pine mortality suggesting multiple interacting factors impacting tree health at stand-level. As such, the hypothesis that SPD is a regionally important decline syndrome and labeling declining southern pine stands as SPD is not supported. Instead, we discuss many abiotic (soil types, climate) and biotic (insects, pathogens, genetics) factors that may be interacting with each other and affecting southern pine health. Finally, we suggest management recommendations for landowners with pine health issues. [ABSTRACT FROM AUTHOR]

Highlights: [•] Species distribution modeling with 10 predictor variables was performed. [•] Water variables were the most important drivers of the potential distribution. [•] The actual distributions of the palms were spatially constrained. [•] Potentially the palms can cover up to 550,000km2 more than their actual range. [•] Big potential for expansion of the current palm resources in western South America. [ABSTRACT FROM AUTHOR]

Abstract: The encroachment of the logging frontier into Western Amazonia, where non-timber extraction has historically driven regional economies, provides an opportunity to explore the practice of multiple-use forest management. Families are now harvesting timber in their Brazil nut (Bertholletia excelsa)-rich community-titled forests, and we examined effects of formal and informal logging (with and without government-approved management plans, respectively) on forest disturbance and natural regeneration (individuals ⩽10cmdbh) of B. excelsa and 10 timber species in Northern Bolivia. B. excelsa regeneration densities 2–5years after timber harvests did not differ between unlogged or logged (formally nor informally) sites; densities were, however, greater in larger logging disturbances (i.e., log landings vs skid trails), corroborating our model in which canopy openness explained regeneration densities. Regeneration of the two most valuable timber species, Swietenia macrophylla and Amburana cearensis, rarely occurred, and only where conspecific trees were felled, implying that population recovery of selected species may need post-harvest silvicultural interventions. In contrast, two other high-value timber species (Cedrela odorata and Dipteryx odorata) responded favorably to disturbances. Contrary to our expectations and reported industrial-scale findings, formal logging resulted in a larger percentage, but still acceptable level, of disturbed area than informal logging (10.6%±0.65 SE vs 6.9%±1.26 SE; p =0.047). Our overall finding that Brazil nut regeneration was unaffected by low logging intensities suggests that combined Brazil nut and timber harvests are compatible under certain circumstances. Still, adhering to legal requirements has been challenging for individual landholders. Preparing legally-required management plans without assistance is difficult, and individual landholders seek to harvest timber over multiple years, which is discouraged by formal logging that indirectly entails one-time extraction of nearly all commercial stems from the approximately 200ha of forest landholders dedicate to timber production. Thus, reconciliation of legal requirements with community conditions is fundamental to long-term success of multiple-use forest management. [Copyright &y& Elsevier]

Abstract: The future of tropical forests may lie in integrating different revenue sources, such as timber, non-timber products and environmental services, to make standing forests more economically competitive with other land uses such as pasture. Therefore, analytical techniques that couple economic models with ecological understanding are an increasingly important tool to promote forested landscapes. This study explores the potential revenue associated with different harvest strategies of the multipurpose tropical tree Carapa guianensis, a species valued for both the high quality oil extracted from its seeds and its mahogany-like timber. We calculated the equal annual equivalent (EAE), a measure of profitability that annualizes net present value, of revenues and costs associated with simulations of sustainable seed and timber harvests. Our specific objectives were (1) to simulate and compare the revenue from ecologically viable seed and timber harvests of C. guianensis in stochastically varying environments; and (2) to calculate the EAE of revenues and costs from seed and timber harvest under different market prices and different oil extraction methods. We found profits from both timber and seed harvest of C. guianensis for oil production, though only when seed presses were available for oil extraction; manual oil extraction had negative returns due to intensive labor requirements. Combined profits from C. guianensis press-extracted seed oil and timber harvests were economically competitive with other common forest use activities that provide communities with cash profits. Combining extraction of NTFPs with timber may provide continuous income while forests recover volume between timber harvests. Combining this income with harvest of other resources in the context of multi-use management may be an economically viable management strategy in similar forests in Amazonia. [Copyright &y& Elsevier]

Abstract: The Brazilian Amazon is a significant source of timber as well as a rich source of non-timber forest products (NTFPs) such as medicinal barks, oils and fruits. Lack of quantity, quality, uniformity and price as well as a lack understanding of NTFPs socioeconomic, cultural or spiritual value and function in societies relegates them to a marginal economic status eclipsed by timber. The data vacuum for most NTFPs is contrasted by the large amount of timber-specific data available for many logged species. Such data sources can offer insights into the extraction level and locations of a subset of species that are valued for both timber and NTFPs. These are referred to as ‘conflict-of-use’ species. In this article we examine three such species, focusing on the Amazonian state of Pará. Pará is situated in the Brazilian “arc of deforestation” and the state accounts for 47% of all timber produced in the Legal Amazon. We describe three highly-utilized Amazonian NTFPs currently logged commercially: (1) Cumuru, Dipteryx odorata, which bears a seed yielding an essential oil employed in the perfume industry and providing income and medicine to rural families; (2) Amapá amargoso, Parahancornia fasciculata, which produces a powerful exudate used as a treatment of respiratory diseases; and (3) Uxi, Endopleura uchi, which produces a nutritious fruit consumed by humans and wildlife. We analyze data from the timber industry indicating the rate of extraction of these species, as well as data regarding their use and value as NTFPs. Results indicate that extraction of these species in logging frontiers contributes to declining access. However, in communities with links to markets, undocumented management systems supply the increasing demand for NTFPs in urban areas. While there are no formal management plans for these species and few scientific attempts made to manage them, small holders have developed local knowledge and innovative techniques to improve productivity, increase density and create multiple-use systems in the face of growing land use pressures. [Copyright &y& Elsevier]

Abstract: This study integrates an ecological process-based growth model, economic description of forestry and derivative-free numerical optimization for analysing optimal management of even-aged Norway spruce (Picea abies [L.] Karst.) stands in fertile southern Finland sites. The process-based growth model is built on fundamental ecological theories of photosynthesis, tree structure and competition between trees. Because of the sound theoretical basis the validity of the optimization results is not restricted to a limited set of states determined by the boundaries of empirical data. The detailed structure of the growth model enables the inclusion of timber quality and its dependence on the size and quality of branches. The optimized variables include the initial stand density, the number, type and intensity of thinnings and the rotation period. The results yield a detailed and coherent picture of optimal stand level management. Comparing the optimal solutions with silvicultural practices suggests that the latter are based on unoptimal thinnings, too low stand density and too long rotation periods. As a consequence a fraction of harvested trees contain too large dry branches and qualify only as low value pulpwood implying that the bare land value remains below 60% of its maximized level. [Copyright &y& Elsevier]

Abstract: Water resources in many catchments in South Africa (SA) are over committed and water is projected to become scarcer. The impacts of plantation forestry on water resources in SA are well known and legislation limits further afforestation. Nevertheless demands for wood continue to grow. A challenge therefore is to increase the production of forest products within water constraints. This paper presents research into the economic and biophysical efficiencies with which indigenous and introduced tree-production systems in SA use water to produce harvestable biomass. Its purpose is to better inform resource allocations. Key findings are that: introduced plantations are more efficient at using water to produce harvestable biomass than indigenous species; the lower water-use efficiencies of indigenous species are due to slow growth rates and not high water-use rates; and the performance of indigenous forests improves when using the economic return per unit of water used – using the residual imputation approach to value the water – because of their lower production costs and higher product prices. Introduced plantations make up the majority of afforested land and total outputs in SA, however, therefore innovative mechanisms are needed to overcome barriers preventing the financing of indigenous forests. Possible financing mechanisms include the UN CDM and REDD programmes and tax breaks for superannuation funds. [Copyright &y& Elsevier]

Abstract: Snags are critical structural features for managing biological diversity in forests of the Pacific Northwest, USA. However, commercial forests in this region often contain reduced numbers of snags compared to unmanaged forests and managers require effective methods to augment snag numbers in harvest units. Therefore, we created snags by topping live trees with a mechanical harvester and studied foraging and nesting use by cavity-nesting birds of these snags in clearcuts in Douglas-fir (Pseudotsuga mensezii) forests along the west slope of the Cascade Mountain Range and east slope of the Coast Range in Oregon, USA. We used a completely randomized design to assign 6 different treatments (single or scattered distribution by 3 different densities) to 31 different harvest units. We created 1111 snags from February 1997 through April 1999 and monitored them from 2–5 years after harvest (1999–2002). Fraction of created snags with nest cavities in harvest units was generally low across all treatments and years of the study, although some individual stands demonstrated increased nesting use with snag age. While the highest fractions of snags with nest cavities were found in units with low density and scattered snags, the mean fraction of snags used for nesting did not differ among treatments. Treatment type, distribution of snags (i.e., scattered or clumped), and associated interactions did not influence fraction of snags used for foraging. However, fraction of created snags used for foraging in all harvest units increased with snag age. Fraction of snags used for foraging was greatest in the low density treatments. While this technique provides managers with a relatively economical option for creating snags, mechanical harvesters cannot be used to create tall, large snags upon which several cavity-dependent species rely and provides only a partial solution to a critical forest management issue. [ABSTRACT FROM AUTHOR]

Abstract: Whole-stand models normally require data on initial stand basal area and dominant height. Dominant height measurements are time-consuming and often imprecise, compromising subsequent predictions. Poplar plantations provide a special case where basal area correlates with site index; a whole-stand model could thus be based on stand basal area. We report a static model constructed by the generalized algebraic difference approach (GADA) for poplar plantations for three different hybrid poplars (Populus × euramericana (Dode) Guinier “I-214”, “MC”, and “Luisa Avanzo”) in northeast Spain. The transition function was based on current stand basal area and was fitted with data from 158 permanent plots ranging from 1- to 17-year-old plantations. Merchantable stand volume was estimated by a volume equation where height was predicted by a height–basal area relationship based on 458 temporary plots. The model differences between clones were compared using the nonlinear extra sum of squares method. Significant differences were detected, while Luisa Avanzo presented the highest merchantable volume at the end of the rotation. Errors in basal area predictions were below 20% within 6 years in the case of Luisa Avanzo and MC clones, and within 3 years in the case of I-214. Our research showed that satisfactory predictions can be obtained using GADA with a single transition function based on an easily measurable variable such as stand basal area. [Copyright &y& Elsevier]

Abstract: Until recently, the most important factors affecting the economics and genetics of the seed crop from seed orchards were considered to be the timing and duration of flowering, variation in fertility and the total number of clones used to establish the seed orchards. Change in climatic conditions however is an emerging factor that could prove crucial regarding the timing of flowering and synchronization among clones and thus, the quality and quantity of seed production. The temporal and spatial variation in flowering phenology and the duration of flowering were studied in consecutive years in a Pinus nigra Arn. seed orchard. Sixty plus trees representing the distribution of the species in Northern Greece were used to establish the seed orchard, and nineteen ramets per clone were planted in a honeycomb experimental design in order to avoid kinship. Temporal variation among clones, as well as spatial variation among ramets within clones growing at different sites of the orchard were recorded, for initiation and duration of male and female flowering. The majority of clones were synchronized in dates of flowering during the year with weather conditions close to the long-term climatic conditions, except for a limited number of clones that were precocious or late flowering. The pronounced variability in climatic conditions over the 2 years strongly affected the flowering and synchronization among clones, resulting in almost complete asynchrony during the xerothermic year, which was characterized by a prolonged mean monthly temperature increase of 2.3°C and a water deficit of 53% in a 7-month-period (November to May). These results suggest that one of the effects of a warmer and drier climate may be the lack of flowering synchronization, as pollen shedding might be completed before female conelets reach the phase of receptivity. The restriction of male parentage to a limited number of clones severely violates the panmixia assumption and could result in fertilization failure. The projected climate change for the Mediterranean region could potentially prove detrimental for fertility and flowering synchronization of forest trees, having consequences on the quantity and genetic diversity of the seed crop in seed orchards, and the natural regeneration of forest trees in forest ecosystems due to the reduced percentage of sound seed. [Copyright &y& Elsevier]

Abstract: The increasing commercial interest and advancing exploitation of new remote territories of the boreal forest require deeper knowledge of the productivity of these ecosystems. Canadian boreal forests are commonly assumed to be evenly aged, but recent studies show that frequent small-scale disturbances can lead to uneven-aged class distributions. However, how age distribution affects tree growth and stand productivity at high latitudes remains an unanswered question. Dynamics of tree growth in even- and uneven-aged stands at the limit of the closed black spruce (Picea mariana) forest in Quebec (Canada) were assessed on 18 plots with ages ranging from 77 to 340 years. Height, diameter and age of all trees were measured. Stem analysis was performed on the 10 dominant trees of each plot by measuring tree-ring widths on discs collected each meter from the stem, and the growth dynamics in height, diameter and volume were estimated according to tree age. Although growth followed a sigmoid pattern with similar shapes and asymptotes in even- and uneven-aged stands, trees in the latter showed curves more flattened and with increases delayed in time. Growth rates in even-aged plots were at least twice those of uneven-aged plots. The vigorous growth rates occurred earlier in trees of even-aged plots with a culmination of the mean annual increment in height, diameter and volume estimated at 40–80 years, 90–110 years earlier than in uneven-aged plots. Stand volume ranged between 30 and 238m3 ha−1 with 75% of stands showing values lower than 120m3 ha−1 and higher volumes occurring at greater dominant heights and stand densities. Results demonstrated the different growth dynamics of black spruce in single- and multi-cohort stands and suggested the need for information on the stand structure when estimating the effective or potential growth performance for forest management of this species. [Copyright &y& Elsevier]

Abstract: Insect damage to production forests has the potential to reduce financial returns by retarding tree growth and causing mortality, however, long-term realised quantification of these losses is rare. In order to help elucidate economic damage thresholds for making spray decisions we capitalised on a natural outbreak of autumn gum moth, Mnesampela privata, in a 2-year-old Eucalyptus nitens plantation. Following the partial chemical control of this insect outbreak we measured the tree growth variables diameter at breast height over bark and height of five differing tree defoliation classes for 75 months following tree damage. At the end of this period a threshold model was fitted to describe the relationship between tree defoliation and realised tree wood volumes. The model revealed that realised stand wood volume was not significantly affected up until defoliation exceeded 60% and then declined sharply after this defoliation level was reached. Further support for this defoliation threshold was evident from multiple comparisons among defoliation classes that showed 50% defoliated trees did not have significantly different wood volume compared to more lightly defoliated trees, but did have significantly greater wood volume compared to trees that were 72% or more defoliated. To determine if the realised differences in wood volume resulted in differences in yield over a plantation rotation the E. nitens growth model NITGRO was used to on-grow trees to age 15 years for a ‘best case’ (type 1 growth response, constant growth rates from last inventory until harvest) and ‘worst case’ (type 2 growth response, divergent growth rates from last inventory until harvest) scenario. The threshold model was then fitted to the outcomes of both scenarios and the economic consequences of defoliation were clearly dependent on the growth function assumed. [Copyright &y& Elsevier]

Abstract: The few studies that have assessed the long-term patterns of re-use of tree cavities by bats all concern North American bats. We studied long-term re-use of tree cavities by two species of European bat, Daubenton''s bats (Myotis daubentonii) and noctules (Nyctalus noctula). Cavities were inspected during consecutive years via direct capture of bats (more than 340 positive capture events, ca 2950 captured bats), observations of emerging bats, or by listening for bats during the early evening when bats emit typical vocalization (over 160 positive checks, over 450 observed bats). Between 1968 and 2007, we found 80 tree cavities used by bats (mostly excavated by woodpeckers) in the Czech Republic. Although more than half of the cavities were occupied for ≤4 summers, 28 cavities (35%) were re-used for 5–10 years. The longest period a cavity was used was 11 and 16 years for Daubenton''s and noctule bats, respectively. Sixteen tree cavities (20%) were occupied solely by Daubenton''s bats and 33 cavities (41%) were occupied only by noctules. The other 31 cavities (39%) were used by both species, either at separate times or simultaneously. Our data suggest that the larger volume of a cavity, the longer duration of re-use and the greater the probability of being occupied by both species. Continuous excavation of cavities by woodpeckers prevented the overgrowth of old cavities by calluses, which keep cavities accessible to bats. We suggest that woodpeckers may be the most important providers of suitable roosts for forest bats in Central Europe. Roosts were found in both economically valuable trees (Quercus robur and Tilia cordata) and less valuable tree species (Salix fragilis and Alnus glutinuosa). Economically valuable trees in our study area were long-lived and likely provide roosting habitat for longer periods but matured at a greater age. However, less economically valuable trees reached maturity and started to decay in a relatively short time, which may provide suitable cavities at a younger age. Maintaining both types of trees within forests may help provide suitable roosting oportunities for tree-dwelling bats in the Czech Republic. [Copyright &y& Elsevier]

Abstract: Forestry practices integrating ecological and social criteria have been replacing those based only on economic values. Traditional silviculture, such as shelterwood cuts (SC), transforms uneven-aged original stands to an even-aged managed forest. Recently, other methods have proposed to conserve some of the original heterogeneity of the old-growth forests. One proposal leaves 30% of the timber quality forest area as aggregated retention and 20% basal area as dispersed retention. The aim of this study was to analyze the feasibility of timber management with aggregated and dispersed retention in Nothofagus pumilio old-growth forests by analyzing timber and harvesting yield potential compared with traditional regeneration systems. Also, remnant tree stability of aggregated retention was analyzed. Timber yield potential of old-growth forests varied from 136 to 479m3 ha−1 across a site quality gradient. High grading cutting improved yield index (timber volume and harvested basal area (HBA) ratio of 7.9m3 m−2). In contrast, this index decreased in clear-cuts (4.7m3 m−2) and shelterwood cuts (4.9m3 m−2). The index also decreased in the aggregated and dispersed retention treatment (5.1m3 m−2), but with higher timber harvested volumes. Windthrow of remaining trees in aggregated retention was related to time, being significantly higher during the first year after harvesting. Windthrow was affected by crown class and position into the aggregates of the remnant trees as well as site quality of the stand. Regeneration methods with aggregated retention were feasible across the entire site quality gradient, and economic losses were not significant when compared to shelterwood cuts. The method also resulted in stability of the remnant overstory, which maintained the ecological conditions to ensure biodiversity conservation and continuity of harvested stands. [Copyright &y& Elsevier]

Abstract: This synthesis examines international opportunities for utilizing biomass for energy at several different scales, with an emphasis on larger scale electrical power generation at stand-alone facilities as well as smaller scale thermal heating applications such as those at governmental, educational, or other institutional facilities. It identifies barriers that can inhibit bioenergy applications, and considers international cases of successful bioenergy production with a focus on Europe and Brazil. Based on the review of international bioenergy applications, important ecosystem service issues having relevance to western U.S. forests are discussed, including hazardous fuel reduction, community development, and sustainability of the wood products industry. [Copyright &y& Elsevier]

Abstract: The ecosystem service concept has been proposed as a meaningful framework for natural resource management. In theory it holds concomitant benefit and consequence for the forest product sector. However, numerous barriers impede practitioners from developing concrete and enduring responses to emerging ecosystem service markets, policies, and initiatives. Principle among these barriers is that the ecosystem service concept has a complex history, numerous definitions in use, and an astounding diversity in rationale and application. This article provides a conceptual review of ecosystem services and its economic foundations, distinguishes among several current definitions of the term and their relatedness to strategies in practical application, discusses diverse approaches to valuation, and explores potential for future relevance in forest product and other sectors. [Copyright &y& Elsevier]

Abstract: Increased urbanization in many societies is having a negative impact on vitality of rural areas. To maintain the vitality of these areas governments have employed a variety of policies, some of which are designed to facilitate innovation and enhance landowner innovativeness. However, little research has investigated the antecedents to landowner innovativeness and whether innovativeness positively impacts economic performance in this setting. The present study investigates these issues in the context of Norwegian forestland owners and their involvement in non-timber forest products and services (a form of ecosystem services). The authors present a conceptual model hypothesizing that social networking, entrepreneurial climate, and a learning orientation each have a direct, positive impact on landowner innovativeness and innovativeness has a direct, positive impact on economic performance. Property size is included as a moderating variable. Data were collected via a mail survey and a total of 683 useable responses were received reaching an adjusted response rate of 35%. Results show that social networking and a learning orientation positively impact innovativeness, but that entrepreneurial climate does not. Innovativeness was found to positively impact economic performance. The authors outline implications of the findings that may be used by policy makers, landowners and research. [Copyright &y& Elsevier]

Abstract: The effects of silviculture on wood and tracheid properties, and economic returns of Norway spruce (Picea abies (L.) Karst.) were investigated in two case studies, one comparing different thinning intensity in southeastern Finland and the other considering the effects of optimal nutrient addition in northern Sweden. Models for predicting the wood and tracheid properties of Norway spruce were integrated into a distance-independent process-based growth and yield model. Increasing the thinning intensity resulted in a lower mean wood density, tracheid length, and latewood proportion in harvested wood. Wood density and tracheid length of harvested pulpwood slightly decreased in later thinnings and final cuts. Thinning regimes with high early growing stock and decreasing later growing stock were most profitable. Nutrient addition accelerated volume growth and increased the value growth. The increase in volume growth due to nutrient addition more than offset the economic influence of the loss in wood density and tracheid length. [Copyright &y& Elsevier]

• The leaf economics spectrum is narrower in New Zealand than in European forests. • Sycamore maple increases photosynthetic efficiency of New Zealand evergreen forests. • Sycamore appears a 'pre-adapted' alien species which fills a formerly empty niche. Understanding the mechanisms behind the successful invasion of alien plant species remains a significant research challenge in invasion ecology. There are surprisingly few cross-continental comparative studies which investigated interspecific trait differences between native and invaded ranges. Here, we compare leaf functional traits of sycamore (Acer pseudoplatanus L.), a deciduous tree species native to Europe and invasive in New Zealand (NZ), to co-occurring resident woody species in both the native and invaded ranges. We analyze a suite of 14 physiological traits on individuals growing either in shade or in sun light conditions. Despite similar environmental conditions, the leaf economics spectrum of forest communities is narrower in NZ than in France. Sycamore extends the leaf economics spectrum of the recipient community towards greater photosynthetic efficiency in the invaded range at a relatively low construction cost. This feature increases the competitive advantage of sycamore over native species. Biogeographic history likely has resulted in a native insular temperate forest community in NZ with unoccupied trait space along the leaf economics spectrum, making these communities susceptible to invasion by 'pre-adapted' alien species, according to the Evolutionary Imbalance Hypothesis. Sycamore may thus successfully invade NZ evergreen forests simply because it fills a functional gap at the fast return end of the leaf economics spectrum, corresponding to a formerly empty niche. As a consequence, forest management can hardly extirpate the invasive alien tree. [ABSTRACT FROM AUTHOR]