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Any-aged forest management (AAF) is a means to reduce clear-felling without compromising profitability or timber production. The concept of AAF is to choose between clear-felling or thinning one harvest at a time based on what is better at that time in terms of the management objectives for the forest. No permanent choice is made between rotation forest management (RFM) and continuous cover forestry (CCF). Optimized AAF is never less profitable than RFM or CCF because all cutting types of both RMF and CCF are also allowed in AAF. This study developed a new set of guidelines for managing boreal forest stands under AAF when the forest landowner maximizes economic profitability. The first part of the guidelines indicates whether the stand should be cut or left to grow. This advice is based on stand basal area, mean tree diameter, minimum allowable post-thinning basal area, site productivity, and discount rate. If the optimal decision is harvesting, the second instruction determines whether the harvest should be clear-felling or thinning. In the case of thinning, the remaining two steps determine the optimal harvest rate in different diameter classes. The guidelines were developed using two different modeling approaches, regression analysis, and optimization, and applied to two Finnish forest holdings, one representing the southern boreal zone and the other the northern parts of the boreal zone. The results show that AAF improves profitability compared to current Finnish management instructions for RFM. The use of clear-felling also decreased the lower the minimum acceptable post-thinning basal area of the stand. [ABSTRACT FROM AUTHOR]

In the current context of participative and multifunctional silviculture, natural regeneration of pedunculate oak (Quercus robur L.), in pure or mixed stands, is a major problem of European silviculture. In countries such as France, Croatia, Great Britain, where mast years of pedunculate oak are quite frequent (from 2-3 years to 5-6 years, seldom 8-10 years), the species is regenerated under the shelter, dominantly by uniform shelterwood cuttings, with a short regeneration period (maximum 4-5 years), characteristic to the light-demanding species. In Romania, the species was regenerated in the past also by uniform shelterwood cuttings, considered not appropriate to the ecology of pedunculate oak by favouring mixed broadleaved tree species, more shade-tolerant. Consequently, especially after 1948, uniform shelterwood cuttings were replaced by group shelterwood cuttings, with a regeneration period of gaps/openings of 2-4 years and of 10-15 years at stand level. In pure and mixed stands of pedunculate oak, the application of silvicultural systems should not target the strict respect of the theoretical background of group shelterwood cuttings, but be correlated with the establishment, growth and development of natural regeneration, which is often irregular / uneven. Therefore, we consider that the best adapted silvicultural system for the regeneration of pedunculate oak should be a combination of uniform and group shelterwood systems, which should also target the limitation of logging damages. [ABSTRACT FROM AUTHOR]

Background and Purpose: The study aims at comparing two (over 100 years old) floodplain oak-predominated forests in the Czech Republic (CZ) with two in of Croatia (HR) with regards to: i) their structure and yield and, more specifically, ii) individual oak tree characteristics including acorn production. Materials and Methods: In both countries a different silvicultural concept is preferred (CZ: clear-cutting management with artificial regeneration, HR: shelterwood management with natural regeneration). The main research goal was to create a basic decision tool for forest managers and open some questions for future research. Results: Despite the different natural and management practices, the total standing volume of floodplain forest was found to be similar in both countries, ranging from 500 to 700 m3·ha-1 (basal area: 34-41 m2·ha-1). In CZ generally more poor structure diversity was detected. Although in CZ the number of crop oaks (130-160 oaks per hectare) was almost double as compared with HR, the CZ oaks had shorter crowns, almost twice smaller crown projection, lower mean volume and lower share of valuable assortments. Conclusions: Despite the total standing volume of oaks in HR being lower than in CZ, the total yield was observed in Croatia (loss in CZ ca. 22,000 €·ha-1). The acorn density and quality were generally higher in HR with a more even distribution as well. Despite more favourable climatic conditions in HR, the currently used management system in CZ floodplain forests should be gradually converted to the Croatian model with a multi-layered forest structure, more focused on individual tree growth and stability with high economical value and high reproductive potential.

Coppiced forests were the main source of firewood, brushwood, and charcoal for rural and urban settlements’ basic needs such as cooking food and domestic heating for thousands of years and up to the mid-20th century in many European countries and, specifically, in Mediterranean countries. The global diffusion of fossil fuels reduced this leadership and the coppice system turned, to some extent, to a reminder of the past. Nowadays, the ongoing global changes and the related green-economy issues call for resilient systems and effective bio-energy producers. These issues have caused a second turning point and the coppice has returned fifty years later to play a role. A review of the silvicultural system has been carried out with a special focus on the changes which have occurred in between, taking Italy as a consistent case-study. The analysis is mainly framed upon the long-term research trials established by the CREA-Forestry Research Centre in the late sixties, to find out adaptive management strategies and overcome the system’s crisis. The findings and further knowledge achieved so far on the dynamics and functioning of coppice forests in the outgrown phase, both as natural evolutive patterns and silviculture-driven processes, are highlighted in this paper. They provide useful tools to handle the management shift regarding forthcoming issues, i.e. the current role attributable to the coppice system within the changing environment and the renewable energy demand. The basic features of each management area and their complementarities within the current framework are outlined.

Highlights • Dead wood dynamics during whole shelterwood cutting cycle was studied in 70 stands. • Changes in dead wood composition increased with cutting intensity. • Shelterwood does not sustain larger dead-wood pools than clear-cutting system. • Shelterwood can stabilize total dead-wood volume, but its turnover is high. • Almost all snags were destroyed during regeneration cuttings. Abstract Shelterwood is commonly assumed to be a more nature-friendly silvicultural system than clear-cutting. However, dead-wood pools – a key characteristic of natural forest – have been seldom compared between these systems. We investigated how shelterwood harvesting influences the dynamics of different dead-wood fractions in Estonia, where the predominant forestry model is clear-cutting based but ‘seminatural’ (using native tree species and, to a significant extent, natural regeneration). We measured dead-wood pools in 49 Scots pine-dominated stands (representing all shelterwood harvesting stages), and in 11 pine-dominated and 10 Norway spruce-dominated stands as before-after experiments (1st stage only). We analysed dead-wood amounts in relation to site conditions and the proportion of timber harvested, and we compared the shelterwood impacts with published estimates from Estonian clear-cuts. Fine woody debris (5–9.9 cm) increased with the harvest. The volume of coarse woody debris was 19–27 m3 ha−1 in uniform shelterwood stands in pine forest (0–25 years after the first harvest); 63 m3 ha−1 in strip shelterwood stands in spruce forest (immediately post harvest). In before-after experiments, post-harvest dead-wood amounts depended on fraction and harvesting intensity, which determines the balance between the input of new debris (logs; stumps) and the loss of pre-existing standing and downed dead trees. After the first shelterwood harvesting, dead-wood pools remained relatively stable, which contrasts with the large fluctuations after clear-cutting. In the long term, however, shelterwood did not sustain generally larger dead-wood pools than the clear-cutting system in seminatural forestry setting. The issue to be resolved in both types of regeneration cuttings is the near-complete loss of standing dead trees, which probably requires new harvesting techniques. [ABSTRACT FROM AUTHOR]

The main objective is to improve a method that aims at evaluating forest multifunctionality from a technical and practical point of view. A methodological approach - based on the index of forest multifunctionality level - is proposed to assess the “fulfilment capability” of a function providing an estimate of performance level of each function in a given forest. This method is aimed at supporting technicians requested to define most suitable management guidelines and silvicultural practices in the framework of a Forest Landscape Management Plan (FLMP). The study area is the Matese district in southern Apennines (Italy), where a landscape planning experimentation was implemented. The approach includes the qualitative and quantitative characterization of selected populations, stratified by forest category by a sampling set of forest inventory plots. A 0.5 ha area around the sample plot was described by filling a form including the following information: site condition, tree species composition, stand origin and structure, silvicultural system, health condition, microhabitats presence. In each sample plot, both the multifunctionality assessment and the estimate of the effect of alternative management options on ecosystem goods and services, were carried out. The introduction of the term “fulfilment capability” and the modification of the concept of priority level - by which the ranking of functions within a plot is evaluated - is an improvement of current analysis method. This enhanced approach allows to detect the current status of forest plot and its potential framed within the whole forest. Assessing functional features of forests with this approach reduces the inherent subjectivity and allows to get useful information on forest multifunctionality to support forest planners in defining management guidelines consistent with current status and potential evolutive pattern.

Aim of the work is to provide further knowledge on the silvicultural system applied to Quercus cerris hight forests in the Molise Region (Central Italy). An historical analysis, based on a number of forest management plans applied since 1940 referred to 19 municipalities and on other historical documents, is provided in the paper. Forest management has been traditionally applied in the Molise Region and therefore is at now possible to reconstruct in detail the management of the forests of Molise Region. The historical study has been integrated with the analysis of a chronosequence including four steps of stand development in a Turkey oak stand: the regeneration phase (1-2 yrs) - the unthinned young stand (46 yrs) - the unthinned adult stand (aged 60 to 100) - the mature stand (126 yrs). Mensurational surveys were carried out at each phase in order to characterize both stand structure and derive information on the silvicultural practices applied in the past, but not documented in the available papers. The stand age was determined by tree coring and count of annual rings. At the beginning of the last century, the silvicultural system to be applied in oak high forests wasn’t strictly defined and a particular kind of selection cutting was carried out. It was named taglio a salto per sezioni i.e. “compartment selection cutting”, partly leading back to a real selection cutting, partly to a shelterwood system. The use of the reported silvicultural system gave rise to irregular forest structures and led to management problems well-described in the management plans at the end of 1940s. Another consequence of the applied practices was the absence or the inadequate natural regeneration establishment. The contemporary unregulated practice of grazing the forest floor contributed to the unsuccessful regeneration and made the situation worse. The presence of an understorey layer made up by sproutings from Carpinus betulus stools clearcutting, was a further hindrance to the establishment of natural oak regeneration. In the fifties, the rate of forest management increased as a consequence of the coming up economic concern in sleeper production. The silvicultural shelterwood system was therefore codified. The system resulted to be more effective and adopted up to the present time. The traditional shelterwood system was based on a 90 yrs rotation length, three thinnings performed from the age of 25 up to 75, time of the seed cutting with a release of 90 trees per hectare. In the seventies, following the much more reduced and even null concern in wood production from oak high forests, practices into the same forests were suspended or postponed. At now, the renewed concern for fuelwood production, the only assortment marketable, as well as the increased attention paid to the multifunctional role of these forests, made again actual the problem of oak high forest management. The effectiveness of shelterwood system is the main outcome of the documental analysis performed. The study of the Carovilli’s chronosequence confirmed the close link between the current stand structures and the prescribed rules adopted in the past, in accordance with the management plans. The experimental trials in progress are now focused at defining an improvement of the shelterwood system practice as for the following issues: reduction of cutting areas; establishment of a more complex structural mosaic at neighbouring forest patches, setting up of a consistent release of seed trees i.e. number and dendrotypes to be selected at the purpose, with a special care to the crown cover to the forest floor, effective control of the understorey development due to the resprouting of Carpinus betulus stools, to enhance the establishment of oak natural regeneration.

The state-owned pine forests on the coast of Ravenna and Ferrara: analysis of forest and structure types for choice of silvicultural system in the planning process. Results of the analysis on typology and structure of state forests dominated by maritime pine (Pinus pinaster Ait.) are reported. These formations grow on a narrow coastal belt between Cervia (Ravenna) and Volano (Ferrara), in the Emilia-Romagna region (Italy). The aim of the study is to support the proper silvicultural system in order to satisfy multiple use of pine forests using the analysis of forest types and model types of structure. Main ecological and structural features of principal pine forest types and experimental criteria on silvicultural systems are explained.

Forests have been subject to human intervention since the inception of human civilization. With enhanced knowledge, understanding and capacity humans exert an increasing pressure and influence on forests. Forests in general have undergone different ownership patterns. The requirements for forests have changed over time. The objectives of forest management are shifting from timber production to biodiversity conservation and nature protection. On the other hand, in many places the forests are dwindling due to the anthropic pressure. The management paradigms are changing in response to these triggering mechanisms. In this paper an attempt has been made to summarize the evolution of forest management practices and discuss some recent trends in forest management.

We review the management of Eucalyptus species under a coppice-with-standards (CWS) silvicultural system. CWS management results in product diversification, permitting production of small and large scale timber from the same stand. Eucalyptus species are suitable candidates for CWS management because: there are large worldwide plantation areas, sprouting capacity is high, and eucalypts are multipurpose species. We discuss (1) short rotation Eucalyptus coppice management for energy and pulping and (2) Eucalyptus seedling management for solid wood products. We review the literature and discuss experiences with Eucalyptus managed under the CWS system. We also assess projects dealing with Eucalyptus coppice management, stand density regulation, pruning, and stand and wood quality. The growth environment of the standard trees (heavy competition up to the first harvest, free growth afterwards) coupled with long rotations (>20 years) results in high quality logs for solid wood products. Early pruning should be applied to enhance wood quality. We propose a system for the silvicultural management of Eucalyptus under the CWS system, elaborating on the consequences of initial planting density, site productivity, and standard tree densities as well as timing of basic silvicultural applications. [ABSTRACT FROM AUTHOR]

Abstract: We investigated survival and growth responses of planted and advance natural regeneration species of varying shade tolerance to partial retention harvesting in moist warm Interior Cedar-Hemlock (ICHmw2) and dry cool Montane Spruce (MSdk) ecosystems of southeastern British Columbia, Canada. Treatments included three levels of overstory basal area retention (none, light (∼25%), or heavy (∼50%)) installed by two harvest methods (handfelled or a pushover falling technique being tested for its ability to control the spread of root disease). After 10 years, growth of both planted and natural regeneration species of varying shade tolerance tended to increase with decreasing overstory retention and associated increases in light availability. In contrast, significant survival responses to retention level were lacking except in the case of shade-intolerant western larch. Harvest method had a variable effect on regeneration survival and growth. Where significant responses did occur, they were generally attributed to harvesting effects on the characteristics of planting microsites rather than root disease spread. Natural regeneration densities at the ICHmw2 site were high at all retention levels, whereas stocking was less consistent at the MSdk site. We concluded that moderately shade-tolerant to shade-tolerant interior spruce and western redcedar can, under conditions similar to those of our study sites, be successfully established under overstories of up to approximately 25m2/ha basal area, but that growth performance is likely to be significantly lower than in clearcuts. Despite early survival issues, conclusions regarding Douglas-fir were similar. Poorer survival and vigour of shade-intolerant western larch suggested this species is not suitable for regeneration in partial retention systems where timber production is the primary objective. Where non-timber objectives predominate, survival and acceptable growth of even a small proportion of larch could add to the diversity of the regenerating stand. [Copyright &y& Elsevier]

Abstract: Excessive slash loading could pose a problem for the regeneration of the serotinous lodgpole pine especially in forests at higher elevation where soil temperature is limiting. In the past, these forests have commonly been harvested using full-tree harvesting where trees are processed at roadside; however, recently cut-to-length harvesting has become a more frequent harvesting method. In cut-to-length harvesting the harvested trees are processed in the block, as a result slash accumulation is much higher on these cutblocks. In an experimental field trial, the cone distribution, natural lodgepole pine regeneration, and the growth and establishment of planted lodgepole pine were evaluated in response to slash load, drag scarification, and mounding after cut-to-length harvesting of high elevation lodgepole pine stands in the Rocky Mountains. Twelve sites were established, each contained six plots which were randomly assigned to six treatment combinations of two slash removal (slash and slash removed) and three mechanical soil preparation treatments (no soil preparation, drag scarifying, and mounding). The slash removal reduced slash volume by more than 50% but also reduced the number of lodgepole pine cones available for regeneration by over 33%. However, soil mechanical treatments offset this effect as fewer cones were necessary to achieve high natural pine regeneration densities. Drag scarification of plots resulted in 12 times the number of pine seedlings compared to the non-prepared plots. Although slash removal did not have an effect on the number of naturally regenerated lodgepole pine seedlings, it had a positive effect on their growth performance. Conversely, planted pine seedlings had lower mortality and better growth in soils that had been mechanically prepared and had the slash removed; however, the growth effects became only apparent 4 years after planting. While slash removal and mechanical soil preparation did increase soil temperatures; the slash removal treatment had a more transient effect on soil temperatures than soil preparation. Differences in soil temperature decreased over time which appeared to be mostly driven by a warming of the soils in the plots with no soil preparation, likely a result of the decomposition of the finer slash and feathermosses. Overall, it appears that surface disturbance on these high elevation sites had a far greater effect on lodgepole pine regeneration and growth than the increased accumulation of slash as a result of cut-to-length harvesting. [Copyright &y& Elsevier]

Uneven-aged management of conifer plantations is proposed as a way to increase the value of these forests for the conservation of bird diversity. To test this assumption, we compared the impact of four common silvicultural systems on bird communities, defined by cutblock size (large in even-aged silvicultural systems/smaller in uneven-aged silvicultural systems) and tree species composition (spruce/beech) in the Belgian Ardenne where beech forests have been replaced by spruce plantations. The abundances of bird species were surveyed in young, medium-aged and mature stands in 3-5 forests per silvicultural system (66 plots in all). The effect of silvicultural systems on bird species richness, abundance and composition were analysed both at the plot and at the silvicultural system levels. In plots of a given age, beech stands were richer in species. The composition of bird species at the plot level was explained by stand age and tree composition, but weakly so by stand evenness. For the silvicultural systems, bird species richness was signiWcantly higher in even-aged and in beech forests, and bird species composition depended on the silvicultural system. This study emphasises the importance of maintaining native beech stands for birds and suggests that uneven-aged management of conifer plantations does not provide a valuable improvement of bird diversity comparatively with evenaged systems. [ABSTRACT FROM AUTHOR]

Swedish forestry has successfully developed systems for sustained yield production of wood. Silvicultural techniques are today completely dominated (96%) by clear-felling methods. By contrast, Swedish natural forests and preindustrial cultural woodlands were ecologically and culturally diverse, with a substantial proportion having a continuous tree cover as a response to natural disturbance dynamics and preindustrial agricultural land management. If forest management systems do not mimic this diversity of disturbance regimes sufficiently well, the scope of sustainable forest management to include biodiversity and sociocultural values will not be met. This study estimated the past and present amount of one cultural and two natural disturbance regimes known to deliver continuous tree cover in two study areas located around two important biophysical and sociocultural transition zones in northern and southern Sweden, respectively. Several approaches were used to estimate the amount of remaining continuous tree cover forests. The results indicate that 9-10% of the study areas is made up by site types that historically would have held a large proportion of continuous tree cover forests. Estimates for productive site types show that only 1-2% of these sites remain in southern Sweden and 10-20% in northern Sweden. The data indicate that present management in both study areas is similar. Thus, these differences between the regions will disappear in a few decades. To achieve the aim of Swedish forest and environmental policies there is a clear need to develop and use alternative forest management methods on appropriate sites. [ABSTRACT FROM AUTHOR]

Selection of an appropriate silvicultural system that maintains productivity requires an understanding of the effects of harvest type on post-harvest changes in nitrogen availability. The effects on inorganic nitrogen availability and litter decomposition of various harvesting systems, including partial canopy removal and a range of clearcut opening sizes, were investigated in a dry Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forest in southern British Columbia. We measured concentrations of ammonium and nitrate after 6-week buried bag incubations of forest floor and mineral soil samples in replicated plots within uncut forest, within partially harvested forest, and in openings of 1.7, 0.4, and 0.1 ha, from two to seven growing seasons after harvest. Post-incubation nitrate and the proportion of inorganic N as nitrate in forest floor and mineral soil were elevated from 2 to 7 years after harvesting in the 1.7 ha openings. There was no consistent trend of higher ammonium concentration in either uncut forest or 1.7 ha openings. The proportion of inorganic N as nitrate was consistently the lowest in the uncut forest, and often significantly different from any opening treatment, including partial cutting. The increased proportion of inorganic N as nitrate occurred within 11 m of the uncut forest edge. At very low moisture contents, nitrate concentrations tended to zero only in the uncut forest. Leaching of the increased available nitrate is unlikely because of the large increase in grass biomass that occurs after harvesting, and the dry soil moisture conditions during the growing season. Decomposition of Douglas-fir, lodgepole pine and trembling aspen litters, or forest floor was inconsistently, or not affected by any harvest treatment or by distance from, or aspect of, the edge of the forest. The post-harvest increases in nitrate concentrations cannot be attributed to faster decomposition. [Copyright &y& Elsevier]

• Silvicultural treatments with greater harvest increased short-term downed dead wood. • Downed dead wood abundance decreased within twenty years after harvest. • Downed dead wood shifted from undecayed to decayed material within twenty years. • Forest management systems did not differ in downed dead wood at the landscape scale. Downed dead wood (DDW) is a critical component of forest ecosystems, with DDW dynamics largely affected by rates of input from standing trees to the forest floor and loss through decomposition or removal. Forest management decisions affect DDW dynamics based on the type of silvicultural harvest applied at the stand level and the administration of those treatments across the landscape. The Missouri Ozark Forest Ecosystem Project (MOFEP) is a landscape-scale experiment that tests the effects of three forest management treatments, even-aged management (EAM), uneven-aged management (UAM), and no harvest management (NHM), on forest ecosystems in the Ozark Highlands region of Missouri. In this study, we evaluate the effects of stand-level silvicultural treatments (clearcutting and intermediate thinning in EAM; single-tree selection and group selection in UAM) and landscape-level forest management treatments (EAM, UAM, and NHM) on the volume of DDW and distribution across decay classes over a 21-year period. At the stand level, clearcutting resulted in the greatest short-term increase in DDW volume among the silvicultural treatments. Following harvest, the DDW was primarily within the undecayed classes during the first few years after harvest but shifted to the greater decay classes during the second decade after harvest. At the landscape level, the forest management treatments did not differ in total DDW volume through time, although EAM and UAM had greater amounts of undecayed DDW than NHM shortly after harvest. Across all treatments, the volume of DDW increased through time, likely due to effects of the forest management but also due to background tree mortality related to oak decline during the study period. Overall, our results show differences in effects of stand-level silvicultural treatments on DDW dynamics and highlight the need to consider both stand-level and landscape-level effects of forest management systems in decision making. [ABSTRACT FROM AUTHOR]

• Time-based comparative analysis of forest management was done in permanent plots. • Scientific forest management ensures promising regeneration of intended species. • Intensive regeneration felling in managed block negatively affect species diversity. • Diversity indices are found to be explained by 28–40% through the predictor variables. • Gaps in forest favor growth of both seedling and saplings of Shorea robusta. Implementation of sustainable forest management approaches, balancing mass timber production and intact ecosystem services through maintaining species diversity, has ever been the challenges for policy makers and practitioners in tropical forestry. Scientific forest management (SciFM) is a popular management approach that is increasingly adopted in Sal (Shorea robusta) dominated forests of Nepal, aiming to accelerate timber production and to improve forest condition. Being based on specific management plan, SciFM practices involve application of various silvicultural practices to manipulate forest composition and stand structure referring to the whole rotation period of a particular forest stand. Of the various aspects of SciFM, we aim to quantify the effect of SciFM on species diversity and regeneration dynamics, and compare diversity indices and regeneration attributes between managed and unmanaged forest stand in lowlands of Nepal, through establishment of permanent sample plots and its measurement in 2014 and 2018. Data collection about plant species and regeneration attributes was carried out in 50 sample plots of size 10 m × 10 m, established by stratified random sampling using quadrat method. Data analysis was done by using various diversity indices and compared through paired t -test. We also carried out correlation and regression analysis of diversity indices with predictor variables; such as canopy cover, number of individuals ha−1, basal area ha−1 and site productivity index. Our study found that plant diversity is significantly decreased but the concentration of dominance is significantly increased in managed forest blocks. Diversity indices were found to have a higher degree of relationship with number of individuals ha−1 and canopy cover as compared to site productivity index and basal area ha−1. Similarly, seedling density and sapling density is found to be increased in managed blocks, ensuring the production and productivity of forest stand sustainably. Based on our analysis, we argue that opening of canopy through regeneration felling is important in promoting regeneration establishment and growth but further research is needed to balance the species diversity along with the practice of intensive management interventions. [ABSTRACT FROM AUTHOR]

An experiment was established in 1991-1992 in northern British Columbia to investigate factors influencing natural regeneration rates of Engelmann spruce (Picea engelmannii Parry) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) in three stand structures created by harvesting. Harvest treatments were a 32-ha clearcut, 0.2-ha patch cuts, andsingle-tree selection. Cone crop periodicity was independent of harvesting system. Natural seedfall was higher in the selection treatmentand small patch cut than the clearcut treatment every year. Five years after harvest, the selection and patch cut treatments had 7 times as many spruce germinants and 10 times as many subalpine fir germinants as the clearcut treatment. Seed availability appears to be the primary limiting factor for establishment of both subalpine fir and spruce in the clearcut treatment. For spruce establishment in the selection and small patch cut treatments, availability of both seed and mineral soil seedbeds were limiting factors, while for subalpine fir, germinant establishment appears primarily limited by availability of disturbed forest floor seedbeds. Foresters could increase opportunities for natural regeneration in these subalpine forests by (i) modifying harvest patterns to enhance conifer seed distribution over harvested areas and (ii) applying seedbed preparation treatments prior to anticipated heavy seedfalls. [ABSTRACT FROM AUTHOR]