Search

Most logging businesses in the US South are owned by White males, many of whom are approaching retirement. The purpose of this study was to evaluate the characteristics of logging businesses with a young owner, beginning (new) business owner, and businesses owned by members of a minority group (YBM). In-person interviews were conducted with twelve YBM logging business owners in Florida and Georgia to gather information on business characteristics and perceived barriers to the formation of these businesses. The YBM business owners were more educated, employed more workers, and had similar capital investments relative to other logging business owners. These owners stated that difficulty recruiting quality employees, high startup costs, lack of industry connections, and high insurance premiums were unique obstacles to establishing YBM businesses. Purposeful actions by the forest industry, policymakers, and other stakeholders may encourage the formation and retention of YBM logging businesses. Study Implications: As the current generation of logging business owners leaves the industry, it is important to develop new businesses. New businesses will likely be owned by young owners, mid-career professionals starting new logging businesses (beginning businesses), and businesses owned by members of a minority group (YBM). Targeted efforts by loggers' associations, the forest industry, and other stakeholders that provide business management training, develop a skilled workforce of equipment operators and log truck drivers, and promote policies that result in affordable insurance may encourage the establishment and retention of YBM businesses. [ABSTRACT FROM AUTHOR]

Mammalian mesopredators—mid‐sized carnivores—are ecologically, economically, and socially important. With their adaptability to a variety of habitats and diets, loss of apex predators, and forest regrowth, many of these species are increasing in number throughout the northeastern United States. However, currently the region is seeing extensive landscape alterations, with an increase in residential and industrial development, especially at the expense of existing forest and small‐scale farmland. We sought to understand how important an existing mosaic of working lands (timberland and farmland) in a forested landscape is to mesopredator species. We did this by studying mesopredator occupancy across three land uses (or habitat types): forest reserve (protected), timber harvest (shelterwood cuts), and field (both crop yielding and fallow) in and around a 3200‐ha forest in northeastern Connecticut. We examined coyote (Canis latrans), bobcat (Lynx rufus), fisher (Pekania pennanti), and raccoon (Procyon lotor) occupancy using paired camera traps across juxtaposed reserve, shelterwood, and field units from April 2018 to March 2019. We created a priori habitat variable models for each species and season, as well as analyzed the impact of habitat types on each species. Throughout the year bobcats were positively associated with foliage height diversity and had the highest use in shelterwoods and lowest use in fields. Land use utilization varied seasonally for coyotes and raccoons, with higher use of fields than reserves and shelterwoods for half the year and no difference between land uses and the other half. Both species were not strongly associated with any particular habitat variables. Reserve forest was moderate to highly used by all species for at least half the year, and highly use year‐round by fishers. Our findings reveal that a mosaic of intact forest and working lands, timber harvest, and agriculture can support mesopredator diversity. [ABSTRACT FROM AUTHOR]

The conservation and sustainable management of forests across ownership groups of the conterminous USA was assessed using the Montréal Process Criteria and Indicators (C&I) framework using national forest inventory and other data. Sixty-one percent of the forest area in the USA is Privately owned (20% Corporate, 39% Family, and 2% Other Private), 37% is Public (28% Federal, 2% Local, and 7% State), and 2% is within Native American Tribal Reservation boundaries. There are many commonalities across ownership categories, but there are also important differences. A 1.1 million ha yr−1 decrease in Family forestland and a 1.0 million ha yr−1 increase in Corporate forestland (C&I 1.1.a) between 2012 and 2019 are among the main trends with implications for sustainability and influence all other aspects considered through the C&I. The majority of annual timber harvests (C&I 2.d) comes from Corporate (46%) and Family (42%) forestlands. Of the most common species, net growth to removal ratios (C&I 2.d) are less than 1.0 for three species on Tribal forestland, two species on Federal forestlands, and two species on Corporate forestlands. Disturbances (C&I 3.a and 3.b) are relatively common (ranging from 4 to 15% of forestland within an ownership category) across ownership categories with the highest proportion of disturbances being caused by diseases and pests on Federal forestland. Differences in the legal and institutional frameworks across ownership categories (Criterion 7) influence how the forest resources can be managed and how policies, programs, and services can be designed and implemented to help maintain and enhance the flow of forest-based goods and services. This analysis helps illustrate that sustainability is complex, C&I are imperfect, and there are additional elements, such as recreational access and ownership/management objectives, that would be helpful for comparing across ownership categories. But the Montréal Process C&I framework helps elucidate the relative threats among ownership categories, in particular the loss of Family forestland to non-forest uses and the increase in disturbances across most ownership categories, and the relative opportunities across ownership categories, including the sustainable supply of timber from Corporate and Family forestlands and the relatively high tree, and presumably broader, biodiversity especially on Local and Other Private forestlands. [ABSTRACT FROM AUTHOR]

Wood and charcoal were key sources of energy during early industrialization in Europe (18th century), preceding the large-scale exploitation of fossil coal. Past timber harvesting implied land transformation and woodland resources management. Therefore, relict charcoal kilns and historical documents of forest management are important sources of information about past woodland composition and structure. However, ancient charcoal kilns are poorly documented in temperate woodlands in the lowlands of western Europe, especially combined with historical written sources. In this study, charcoal production was investigated in an area in NE France, by combining charcoal and historical sources analysis, along with innovative dating methodologies. Thus, by using both radiocarbon and optically-stimulated luminescence dating, we showed that the activity lasted until recent times (19th–early 20th centuries) and Carpinus was the dominant taxon in charcoal assemblage. Moreover, kiln attributes seemed to be independent of topographical variables. Woodlands in this area were subject to a coppice-with-standards management, where small diameter wood was preferred to produce charcoal and large diameter stems, mainly Quercus and Fagus, were traded as timber. The dominance of Carpinus is rather uncommon in charcoal studies but supports the importance of Carpinus as fuelwood since the Middle Ages, as confirmed by many written sources. [ABSTRACT FROM AUTHOR]

Ergonomic evaluations of forest machines are carried out in isolation due to the lack of an adequate method that makes it possible to correlate the ergonomic variables simultaneously. The aim of this study was to evaluate the ergonomic performance of certain forest machines by using the Integrated Ergonomic Indicator (IEI), capable of correlating ergonomic variables simultaneously. Vibration, noise, heat, illuminance, posture, repeatability, visibility and productivity were obtained from a feller buncher, harvester, forwarder, skidder and processor machines in two work shifts with 24 operators. The ergonomic data were subjected to cluster analysis and standardized by their deviations from the average, being subjected to multivariate factor analysis to determine influencing factors in the composition of the IEI. The indicator for each factor was multiplied by the variance explained for each factor, with the result divided by the total explained variance. The values remained around 0 and the higher the result, the worse the ergonomic condition. The results showed that the variables that most negatively influenced the machines were vibration, noise and lateral visibility which were related to each other. The worst machine under the ergonomic aspect was the skidder, with an IEI of 2.82 and 1.60 for day and night shifts, respectively, caused by shocks and bumps in the work route, and also due to the operators spending a long time with their neck rotated. The best machines were the 8×8 harvester and the forest processor at night, with an IEI of −1.36 and −0.96, caused by vibration, noise and neck with little rotational deviation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Forestry Society of Croatia / Sumarski List Hrvatskoga Sumarskoga Drustva is the property of Forestry Society of Croatia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Managing northern hardwood forests using high-frequency, low-intensity regimes, such as single-tree selection, favors shade-tolerant species and can reduce tree species diversity. Management decisions among family forest owners (FFO) can collectively affect species and structural diversity within northern hardwood forests at regional scales. We surveyed FFOs in the Western Upper Peninsula of Michigan to understand likely future use of three silvicultural treatments—single-tree selection, shelterwood, and clearcut. Our results indicate that FFOs were most likely to implement single-tree selection and least likely to implement clearcut within the next 10 years. According to logistic regression, prior use of a treatment and perceived financial benefits significantly increased the odds for likely use for all three treatments. Having received professional forestry assistance increased likely use of single-tree selection but decreased likely use of shelterwood. We discuss these results within the context of species diversity among northern hardwood forests throughout the region. [ABSTRACT FROM AUTHOR]

Effective forest management is based on the multipurpose use of existing forest resources and its ecological functions. The principle of multifunctionality is focused on sustainable forest management, taking into account environmental, economic, and social factors. The purpose of the research is to analyze development patterns of multifunctional forest management in order to identify the priorities in the forest sector development. The paper defines indicators affecting the level of forestry activities and designates territory zones depending on their qualitative and quantitative characteristics. The analysis of forest use for wood production showed that the annual underutilization of the allowable cut is due to a decrease in the total volume of timber cutting, depressed demand for hardwood of a low commercial quality, insufficient transport development of forests, and the lack of enterprises engaged in advanced processing of semi-subsistence deciduous forest stand. During the studies, it was found that areas, which location is economically advantageous, are more suitable for recreation purposes, as they are better provided with natural resources and are closer to waterbodies (rivers, lakes, reservoirs), possess unique forestland and are more attractive for investments. The paper identifies the problems and promising areas of multifunctional forest management. [ABSTRACT FROM AUTHOR]

In‐stream large wood (LW) is a prominent feature of forested aquatic ecosystems worldwide, yet many questions remain regarding the response of LW patterns to riparian timber harvesting. This paper proposes a conceptual model of wood storage response to harvesting and combines a unique 45 year record of LW with output from a wood budget model to examine changes in LW characteristics and long‐term impacts from riparian logging. The wood budget model is used to predict the timing of minimum storage and assess storage recovery time scales under three scenarios representing different spatial harvest patterns and harvest severity. The impact of harvesting is reflected in the field data: Reductions in wood volume and the loss of large logjams were apparent in channel areas adjacent to logged zones, but wood volume changed less where a riparian buffer was retained. Results from the budget model indicate that impacts from timber harvesting are projected to continue beyond 150 years while riparian forests recover. Minimum modeled LW loads are projected to be nearly 50% lower than preharvest conditions, and minimums occur 50 to 80 years postharvest, depending on the influence of LW transport and proximity to harvesting. In evaluating the conceptual model, harvesting configuration and severity are not found to greatly impact time to minimum storage and recovery, but do impact the magnitude of LW losses. Similar to other studies, these findings indicate that riparian harvesting has an impact beyond the century scale, with major implications for stream channel functionality and aquatic habitat. Key Points: In‐stream wood data spanning 45 years reflect historical timber harvesting, with widespread loss of wood in logjamsUsing a wood budget model, time to minimum storage and to storage recovery are projected as ∼50 and 200 years, respectivelyModel results indicate that harvesting severity impacts the magnitude of wood loss, but less so the recovery time [ABSTRACT FROM AUTHOR]

The growth rate of most tree species in boreal forests will increase with changing climate. This increase is counterbalanced by an increased risk of damage due to extreme weather events. It is believed that the risk of storm damage will increase over time, especially if forests continue to be managed as they are today. In this study, a new landscape-level hybrid forest growth model 3PG-Heureka was developed and simulations were performed to predict the damage caused by storm events in Kronoberg county, over a period of 91 years (2010-2100) with different alternative management regimes under various climatic scenarios (historic, RCP4.5 and RCP8.5). The results indicate that damage caused by storm events could drastically reduce the annual volume increment and annual net revenue obtained from forest landscapes if current forest management regimes are used. These problems can be reduced by adopting alternative management strategies involving avoiding thinning, shorter rotation periods and planting alternative tree species. Alternative management strategies could potentially improve annual volume increments and net revenue obtained while reducing storm-felling. Planting Scots pine instead of Norway spruce across the landscape to minimize storm damage is predicted to be less effective than reducing rotation periods. [ABSTRACT FROM AUTHOR]

• UAV live-feed surveys were as effective as the conventional survey method. • UAV-live feed surveys were more time-efficient than the conventional survey method. • UAV-created map surveys were less effective than the conventional survey method. • Developed a standardized framework for UAV-based monitoring of forestry BMPs. Compared to undisturbed areas, timber harvest activities, including road construction, skid trails, and stream crossings, exhibit the potential for causing erosion and sedimentation if forestry best management practices (BMPs) are not implemented. Forestry BMP monitoring serves as a tool to evaluate BMP implementation status. Conventional on-the-ground BMP monitoring has contributed substantially to assessing BMP implementation. However, conventional on-the-ground surveys can be time consuming. Unmanned aerial vehicles (UAVs) have been rapidly emerging as a new tool for local-scale monitoring. In this study, we evaluated the feasibility and potential of UAVs for monitoring forestry BMPs in the coastal plain of southeastern United States. We compared the performance of UAV-live feed surveys and UAV-created map surveys with conventional on-the-ground surveys across major BMP categories on 30 study sites using BMP guidelines and implementation survey questions from Alabama, Georgia, and Florida for the sites specific to that state (10 sites in each state). The UAV-live feed surveys involved real-time assessments conducted using the live feed function, enabling on-the-spot evaluations. Whereas the UAV-created map surveys entailed autonomous UAV flight to collect imagery specifically for generating maps and facilitating subsequent assessments. We found that using a UAV for monitoring BMPs efficiently provided an overview of a timber harvest area from above. UAV-live feed surveys were as effective as conventional on-the-ground surveys across all major BMP categories. Specifically, the Cramer's V correlation between the responses from UAV-live feed and conventional on-the-ground surveys for all BMP categories, was 0.95 (p < 0.0001) for detecting implemented BMPs and 0.86 (p < 0.0001) for detecting when BMPs were not implemented but needed to be. UAV-created map survey results vs. conventional on-the-ground surveys were not as effective (V of 0.79 for detecting implemented BMPs and 0.46 for detecting BMPs not implemented but needed). Waste and stream crossing BMP implementation were the most difficult to verify using the map surveys, which was not an issue with the live feed surveys due to the capability to evaluate those BMPs at different camera angles. While UAV-created map surveys may be less effective, they provide an observation record that includes a map of the site. This project also developed a standardized framework for using UAVs to monitor forestry BMPs, including instructions and procedures for conducting UAV-live feed and map surveys. In conclusion, a UAV using the live feed function in the field is a feasible option to monitor forestry BMPs. [ABSTRACT FROM AUTHOR]

Timber is harvested in the United States by thousands of independent logging businesses. Fully mechanized, wholetree harvesting systems are the most common and most productive systems in most states, although chainsaw systems persist in mountainous terrain and cut-to-length systems are common in the Lake States. Southern loggers are most productive, with many logging businesses producing more than 70,000 tons yr-1 while loggers in other regions average <30,000 tons yr-1. Both the number of logging workers and logging businesses declined by 2% yr-1 in 1990-2016. However, despite consolidation, most studies report adequate or excess logging capacity. The logging sector faces a number of challenges, such as the need to recruit new business owners when the current generation retires, declining markets in some areas, and reduced working days per year. However, the logging sector has proven resilient and innovative over the years with significant improvements in productivity and environmental performance. [ABSTRACT FROM AUTHOR]

The Amazon rainforest lies within the most diverse forest ecosystem in the world. However, a large part of the tropical rainforest is being degraded because of timber harvesting without any sustainability criteria and owing to a limited understanding of the effects of forest exploitation. The Ecuadorian Amazon (EA) is part of the Andes Amazon (AA), an area covered by five countries (Venezuela, Colombia, Ecuador, Peru and Bolivia). This research identified the patterns of legal timber harvesting in the EA and determined current trends with respect to mostly harvested forest species. Two harvesting programs aimed at small farmers prevail in the EA: first, naturally regenerated trees felling program, and simplified timber harvesting programs in native forests. Considering the surface and volume of logging, significant differences were detected between logging procedures and ecosystems in the region. Two hundred and thirty-two genera are registered for harvest and, 51.93% of the total harvesting volume comes from eight genera and ten species. This research shows that in fallows of fragmented forest ecosystems, small farmers are harvesting fast-growing pioneer species. Maintaining a sustainable production in timber harvesting depends, by and large, on the harvesting and felling programs established on small farms. [ABSTRACT FROM AUTHOR]

In order to accommodate foreseen climate change in European forests, the following are recommended: (i) to increase the number of tree species and the structural diversity; (ii) to replace unsuitable species by native broadleaved tree species, and (iii) to apply close-to-nature silviculture. The state forest department of Baden-Württemberg (BW) currently follows the concept of Forest Development Types (FDTs). However, future climatic conditions will have an impact on these types of forest as well as timber harvesting operations. This Geographic Information System (GIS)-based analysis identified appropriate locations for main FDTs and timber harvesting and extraction methods through the use of species suitability maps, topography, and soil sensitivity data. Based on our findings, the most common FDT in the state forest of BW is expected to be coniferous-beech mixed forests with 29.0% of the total forest area, followed by beech-coniferous (20.5%) and beech-broadleaved (15.4%) mixed forests. Where access for fully mechanized systems is not possible, the main harvesting and extraction methods would be motor manual felling and cable yarding (29.1%). High proportions of large dimensioned trees will require timber extraction using forestry tractors, and these will need to be operated from tractor roads on sensitive soils (23.0%), and from skid trails on insensitive soils (18.4%). [ABSTRACT FROM AUTHOR]

In this study, we characterised the temporal-spectral patterns associated with identifying acute-severity disturbances and low-severity disturbances between 1985 and 2011 with the objective to test whether different disturbance agents within these categories can be identified with annual Landsat time series data. We analysed a representative State forest within the Central Highlands which has been exposed to a range of disturbances over the last 30 years, including timber harvesting (clearfell, selective and thinning) and fire (wildfire and prescribed burning). We fitted spectral time series models to annual normal burn ratio (NBR) and Tasseled Cap Indices (TCI), from which we extracted a range of disturbance and recovery metrics. With these metrics, three hierarchical random forest models were trained to 1) distinguish acute-severity disturbances from low-severity disturbances; 2a) attribute the disturbance agents most likely within the acute-severity class; 2b) and attribute the disturbance agents most likely within the low-severity class. Disturbance types (acute severity and low-severity) were successfully mapped with an overall accuracy of 72.9%, and the individual disturbance types were successfully attributed with overall accuracies ranging from 53.2% to 64.3%. Low-severity disturbance agents were successfully mapped with an overall accuracy of 80.2%, and individual agents were successfully attributed with overall accuracies ranging from 25.5% to 95.1. Acute-severity disturbance agents were successfully mapped with an overall accuracy of 95.4%, and individual agents were successfully attributed with overall accuracies ranging from 94.2% to 95.2%. Spectral metrics describing the disturbance magnitude were more important for distinguishing the disturbance agents than the post-disturbance response slope. Spectral changes associated with planned burning disturbances had generally lower magnitudes than selective harvesting. This study demonstrates the potential of landsat time series mapping for fire and timber harvesting disturbances at the agent level and highlights the need for distinguishing between agents to fully capture their impacts on ecosystem processes. [ABSTRACT FROM AUTHOR]

In the context of forest management intensification, European countries are attempting to promote the sustainable management of forest landscapes. The aim of this study was to determine the structural dynamics of managed state forest landscapes in the context of changing forest policy. Four landscapes in the North Vidzeme Biosphere Reserve of northern Latvia were studied for the period between 1988 and 2011. The spatial patterns of clearcuts, regenerating stands and uncut stands were analysed using landscape metrics at the class level. For more comprehensive structural analysis, we additionally analysed the stand age structures and spatial pattern characteristics of over-mature stands and woodland key habitats (small voluntarily set-aside forest stands with high biodiversity values in Nordic and Baltic countries) that existed in 2011. The results indicated a substantial increase in the overall landscape structure complexity (measured by the number of patches, edge density and patch isolation at the class level) in three of the four analysed landscapes. At the class level, clearcut harvesting intensity increased after 2000, with the establishment of a new forest policy and management system in state forests combined with an abundance of timber available for felling. Significant increase in clearcut edge density and aggregation, with a corresponding decline of matrix connectivity, coincided with an increase in allowed felling volume by 4 million m for the period between 2009 and 2010 (increase in felling by about 60 % in state forests). Management reform and the introduction of a concentrated felling strategy in state forests also contributed to management intensification. Relatively higher WKH isolation, compared to that of over-mature stands, in all landscapes suggested that setting aside part of these stands could be a means of improving connectivity in the future. We suggest that the integration of landscape ecological principles, such as inclusion of ecological networks or retaining clusters of older stands, into Latvia's forest management plans is needed and would contribute to more sustainable forest management. [ABSTRACT FROM AUTHOR]

In this investigation, three different methods for the harvesting of spruce under otherwise identical conditions were analysed with respect to their greenhouse gas emissions per unit of output: a partially mechanised method using motor saws and draft horses, a more highly mechanised method using motor saws and a forestry tractor and a fully mechanised method with a harvester and forwarder. All the sub-steps from the harvesting of the fallen trees to the transportation to the road were included in the investigated greenhouse gas audit, which followed the rules of a streamlined life cycle assessment. The lowest greenhouse gas emissions were produced by the partially mechanised method (305.7 kg COe ha), followed by the more highly mechanised method (510.5 kg COe ha) and by the fully mechanised method (554.3 kg COe ha). The greatest proportion of the greenhouse gas audit within each method was taken up by the fuel, lubricant and hydraulic oil utilisation. In the horse audit, transportation to and from the site of operation caused the greatest effect (60%). With these results, it could be confirmed that horses when used for logging could be assessed as being more positive with respect to their climate friendliness than large-scale machines despite their lower harvesting capacity per hectare of spruce. However, as this study did not take all environmental impacts into consideration, this relatively better environmental audit for draft horses could be changed when other environmental impacts (e.g. land use) are also included. This possibility should be investigated in further investigations. [ABSTRACT FROM AUTHOR]

Abstract: We studied reuse of Goshawk Accipiter gentilis nests after timber harvesting within 50m from the nest in 31 territories in southeastern Norway. The proportion of nests used in the second or third breeding season after logging (55%) did not differ significantly from that of 27 control nests (67%). Both for all nests (N =58), and for nests with logging closer than 50m (N =31), reused nests differed from those not reused by being situated in a larger area of mature forest, and in forests with a higher proportion of Norway Spruce Picea abies, which gives better cover than Scots Pine Pinus silvestris and deciduous trees. However, a higher proportion of nesting territories with the target nest situated in a Spruce-dominated forest stand seemed to lack alternative nests, probably due to the more intensive timber harvesting in Spruce-dominated landscapes. Hence, Goshawks’ tolerance towards logging may be overestimated in Spruce-dominated forests. We recommend that foresters planning timber harvesting near Goshawk nests focus on the remaining mature forest stand and its structure. In order to maximise the chance of nest reuse, a patch of at least 2ha of suitable mature forest around the nest should be retained. [Copyright &y& Elsevier]

Abstract: This study examines annual ring widths, diameter growth and increment differences of trees at a skid road and the undisturbed area in a pure plantation fir (Abies bornmulleriana Mattf.) forest and compare these data with annual ring widths diameter growth and increment of trees at the skid road edge and undisturbed forest area. The trees growing there commonly display better growth and diameter increment than the trees growing on the skid road. Tree growth and increment on the undisturbed area was found to be about 60% greater than the skid road. [Copyright &y& Elsevier]

Abstract: Over the past two decades, sets of timber harvesting guidelines designed to mitigate the deleterious environmental impacts of tree felling, yarding, and hauling have become known as “reduced-impact logging” (RIL) techniques. Although none of the components of RIL are new, concerns about destructive logging practices and worker safety in the tropics stimulated this recent proliferation of semi-coordinated research and training activities related to timber harvesting. Studies in Southeast Asia, Africa, and South and Central America have clearly documented that the undesired impacts of selective logging on residual stands and soils can be substantially reduced through implementation of a series of recommended logging practices by crews that are appropriately trained, supervised, and compensated. Whether reducing the deleterious impacts of logging also reduces profits seems to depend on site conditions (e.g., terrain, soil trafficability, and riparian areas), whether the profits from illegal activities are included in the baseline, and the perspective from which the economic calculations are made. A standardized approach for calculating logging costs using RILSIM software is advocated to facilitate comparisons and to allow uncoupling RIL practices to evaluate their individual financial costs and benefits. Further complicating the matter is that while there are elements common to all RIL guidelines (e.g., directional felling), other components vary (e.g., slope limits of 17–40° with ground-based yarding). While use of RIL techniques may be considered as a prerequisite for sustaining timber yields (STY), in particular, and sustainable forest management (SFM), in general, RIL should not be confounded with STY and SFM. This confusion is particularly problematic in forests managed for light-demanding species that benefit from both canopy opening and mineral soil exposure as well as where harvesting intensities are high and controlled primarily by minimum diameter cutting limits. These qualifications notwithstanding, since logging is the most intensive of silvicultural treatments in most tropical forests managed for timber, some aspects of RIL are critical (e.g., protection of water courses) whether forests are managed for STY, SFM, or even replacement by agricultural crops. [Copyright &y& Elsevier]

Understory vegetation plays a critical role in boreal ecosystems. Despite this, quantitative evaluation of the factors controlling understory vegetation abundance, diversity, and composition in the most diverse boreal forest region in North America is lacking. This study examined the dynamics of understory vegetation of stands of fire origin and tested effects of overstory composition and logging vs. fire on the understory vegetation dynamics in Ontario, Canada. Understory vegetation communities were sampled in 68 stands of conifer, mixed-wood, and deciduous overstory type ranging from 7 to 201 years postfire for stands of fire origin, and from 7 to 31 years for stands of logging origin. For stands of fire origin, total cover and species richness followed similar trends for the three overstory types and were highest in the intermediate-aged stands (72-90 years). Trends in cover and richness, however, differed significantly for vascular and nonvascular plant groups. Vascular cover and species richness were generally higher under deciduous stands, and lower on older stands, while nonvascular species richness was highest under conifer stands and increased with time since fire. Neither species richness nor compositional turnover was higher under mixed-wood stands; mixed-wood stands were compositionally intermediate to conifer and deciduous stands. Multivariate analysis using multiple-response permutation procedures indicated that understory communities were compositionally distinct for all overstory types and showed no convergence with increasing time since fire. Compared with postfire stands of similar ages, post-logged stands had similar total understory cover and richness. Vascular cover and richness, however, were higher on post-logged stands, and nonvascular cover and richness were lower. Stands of logging and fire origin were compositionally distinct for all overstory types and ages. Compositional differences appeared to be driven by higher preestablished rhizomatous species and few pyrophilic species on post-logged sites. Understory vegetation communities in the central boreal shield appear to support the intermediate disturbance hypothesis. Understory richness, however, was not negatively associated with high cover values as predicted by the intermediate disturbance hypothesis. Moreover, richness appears to be highest on sites with high light availability, suggesting that boreal understory communities are influenced more by plant tolerances for low resources, rather than by competition. [ABSTRACT FROM AUTHOR]

The effects of timber harvesting on stream water quality and efficiency of alternate streamside management zones were evaluated in Pockwock Lake and Five Mile Lake watersheds in central Nova Scotia, Canada. The streamside management zone (SMZ) included a 20 m no cut, 20 m select cut and a 30 m select cut buffer strips along the stream. Water quality of eight streams, six in harvested and two in not-harvested watersheds were monitored for two years before and two years after the harvesting of timber. Nonparametric statistical tests on stream water quality showed that there was significant change in the concentration of potassium in six streams, manganese in five streams, zinc in two streams and total nitrogen in one stream after timber harvesting. There was no significant change in the quality of water in two streams used as control sites in the neighboring watersheds of similar size and hydrological characteristics. The results show that forest management practices were most favorable in streams maintained with 30 m select cut followed by 20 m no cut and 20 m select cut SMZ. The streamside zone width and treatment of select cut or no cut in the zone played an important role in filtering or retaining the minerals in surface water runoff. In buffer zones of similar width, the buffer zone with no cut or forested buffer was relatively more effective at protecting stream water quality than select cut SMZ. The vegetation in the zone may have decreased the flow velocity and increased residence time and thus increased filtration and retention of minerals in the riparian soil. [ABSTRACT FROM AUTHOR]

The model of ‘ecological forestry’ has evolved as a part of the development of the concept of ecosystem management. ‘Ecological forestry’ emphasises that manipulation of a forest ecosystem should consider, and as far as practicable work within the limits of, natural disturbance patterns prior to extensive human alteration of the landscape. This paper evaluates the extent to which forest management practices in jarrah (Eucalyptus marginata) and karri (Eucalyptus diversicolor) forests of south-western Australia align with this view of the characteristics and appropriate silviculture of ‘ecological forestry’. Characteristics and appropriate silviculture of ‘ecological forestry’ are evaluated in relation to (i) the stand level decisions of stand structure and harvest timing and (ii) the landscape level decisions of harvest levels and age structures, and spatial patterns of harvest. Forest management in south-western Australia is found to align with appropriate silviculture under this model of ‘ecological forestry’. Additionally, the landscape triad of areas managed to ‘ecological forestry’ principles, conservation reserves and areas managed to production forestry is in place in the south-western forests of Australia. Strengths and weaknesses in the model of ‘ecological forestry’ and the ability to interpret consistency of practices in the forests of south-western Australia with the characteristics of ‘ecological forestry’ are identified. [Copyright &y& Elsevier]

Pond-breeding salamanders spend most of their lives in forested habitat surrounding the vernal pools where they breed. Timber harvesting has been demonstrated to have negative impacts on salamander populations due to changes in soil temperature, soil compaction, and general degradation of habitat. However, little is known about how long it takes for harvested forest habitat to once again become suitable for salamanders. Questions also remain as to whether salamanders will use an area that has been harvested in recent years if an older intact forest area is available. We used drift fences and pitfall traps to capture adult spotted salamanders (Ambystoma maculatum) and marbled salamanders (A. opacum) migrating to 3 vernal ponds during their breeding seasons. The study area contained tracts of forest that were clear-cut 11-12 years prior to the study. All 3 ponds were surrounded by areas of clear-cut and intact forest and drift fences were placed in both habitat types. Similar numbers of spotted salamanders entered the ponds from clear-cut and intact forest areas. The number of marbled salamanders migrating to the ponds did not differ between areas of clear-cut and intact forest. These results suggest that clear-cut habitats may become suitable for adult pond-breeding salamanders after a relatively short regeneration period. [ABSTRACT FROM AUTHOR]

Abstract: We compared the density and species composition of seedlings and saplings as well as the evidence of browsing by white-tailed deer (Odocoileus virginianus) on recently logged and mature non-industrial private forestland (NIPF) stands in south-central Virginia. Nine stands had been harvested within the past 2 years and the nine mature forest stands had not been harvested within the past 30–40 years. Seedling (trees <0.5m tall) density was similar on recently logged and mature stands. Sapling (≥0.5m tall, but <10cm diameter at breast height) density was more than two times greater on recently logged stands than mature stands, although this difference was not statistically significant. There was no significant correlation between stand basal area and seedling or sapling density. Some evidence of browsing by deer was observed for almost all tree species recorded. For logged sites, 0.9% of all seedlings had evidence of browsing compared to 3.4% of seedlings in mature stands. There was significantly more evidence of browsing on saplings in mature forest stands (22.9%) compared to recently logged stands (6.1%) and browsing evidence significantly increased with increasing basal area. Evidence of high browsing pressure and low sapling density on mature forest stands may indicate a problem with advance regeneration on NIPF stands in this part of Virginia. Logged stands had a significantly higher abundance of seedlings and saplings of yellow-poplar (Liriodendron tulipifera), the most valuable timber species in the study area and one that did not show much evidence of browsing by deer. Logging, however, appeared to promote the colonization of the nonnative invasive species ailanthus (Ailanthus altissima). [Copyright &y& Elsevier]

The two major forms of disturbance in the montane ash eucalypt forests of the Central Highlands of Victoria (southeastern Australia) are clearfell logging and unplanned wildfires. Since the 1930s wildfire has been followed by intensive and extensive salvage-logging operations, which may proceed for many years after a wildfire has occurred. Although applied widely, the potential effects of salvage logging on native flora and fauna have been poorly studied. Our data indicate that the abundance of large trees with hollows is significantly reduced in forests subject to salvage harvesting. This has implications for the persistence of an array of such cavity-using vertebrates as the endangered arboreal marsupial, Leadbeater's possum (Gymnobelidues leadbeateri ). Salvage logging also reduces the prevalence of multiaged montane ash forests—places that typically support the highest diversity of arboreal marsupials and forest birds. Limited research has been conducted on the effects of salvage logging on plants; thus, we constructed hypotheses about potential impacts for further testing based on known responses to clearfell logging and key life history attributes. We predict many species, such as vegetatively resprouting tree ferns, will decline, as they do after clearfelling. We also suggest that seed regenerators, which typically regenerate well after fire or conventional clearfelling, will decline after salvage logging because the stimulation for germination (fire) takes place prior to mechanical disturbance (logging). Understory plant communities in salvage-logged areas will be dominated by a smaller suite of species, and those that are wind dispersed, have viable soil-stored seed remaining after salvage logging, or have deep rhizomes are likely to be advantaged. We recommend the following improvements to salvage-logging policies that may better incorporate conservation needs in Victorian montane ash forests: (1) exemption of salvage logging from some areas (e.g., old-growth stands and places subject to only partial stand damage); (2) increased retention of biological legacies on burned areas through variations in the intensity of salvage logging; and (3) reduction in the levels of physical disturbance on salvage-logged areas, especially through limited seedbed preparation and mechanical disturbance. [ABSTRACT FROM AUTHOR]

Stand structure, the arrangement and interrelationships of live and dead trees, has been linked to forest regeneration, nutrient cycling, wildlife habitat, and climate regulation. The objective of this review was to synthesize literature on stand structural dynamics of North American boreal forests, addressing both live tree and coarse woody debris (CWD) characteristics under different disturbance mechanisms (fire, clearcut, wind, and spruce budworm), while identifying regional differences based on climate and surficial deposit variability. In fire origin stands, both live tree and CWD attributes are influenced initially largely by the characteristics of the stand replacing fire and later increasingly by autogenic processes. Differences in stand structure have also been observed between various stand cover types. Blowdown and insect outbreaks are two significant non-stand replacing disturbances that can alter forest stand structure through removing canopy trees, freeing up available growing space, and creating microsites for new trees to establish. Climate and surficial deposits are highly variable in the boreal forest due to its extensive geographic range, influencing stand and landscape structure by affecting tree colonization, stand composition, successional trajectories, CWD dynamics, and disturbance regimes including regional fire cycles. Further, predicted climate change scenarios are likely to cause regional-specific alterations in stand and landscape structure, with the implications on ecosystem components including wildlife, biodiversity, and carbon balance still unclear. Some stand structural attributes are found to be similar between clearcut and fire origin stands, but others appear to be quite different. Future research shall focus on examining structural variability under both disturbance regimes and management alternatives emulating both stand replacing and non-stand replacing natural disturbances. [ABSTRACT FROM AUTHOR]

The opening or removal of forest canopies during harvesting or land clearing results in a predictable sequence of responses, the descriptions of which appear remarkably similar around the world. Such activities are now widely acknowledged to have adverse impacts upon water quality and in-stream ecology. Sediment delivery, therefore, encapsulates the dominant process by which water resources are impacted and the process that can be best managed to limit off-site impacts. This paper is a review of current processes, and perceptions, of sediment delivery in managed forests. We outline the major components of sediment and runoff delivery as they relate specifically to timber harvesting activities. Whilst much existing research has focused upon soil loss as the major component of timber harvesting impacts, this review highlights both the need for, and benefits from, a conceptual advance in our thinking of sediment delivery. We advocate that by managing runoff delivery pathways and the resultant pattern of hydrological connectivity, we can limit the potential adverse effects of forest harvesting on in-stream water quality. Specific attention is given here to the interaction of the forest road and track network with both sediment and runoff delivery. The result is a comprehensive account of how best to manage timber harvesting for both on-site sustainability and off-site water resource protection.Key words: timber harvesting, sediment delivery, road network, connectivity, best management practices (BMPs). L'ouverture ou l'enlèvement de la canopée, au cours des récoltes ou du défrichement, conduisent à une séquence prévisible de réactions, dont la description semble remarquablement comparable partout au monde. On reconnaît maintenant que de telles activités ont des impacts négatifs sur la qualité de l'eau et l'écologie des cours d'eau. Conséquemment, la déposition des sédiments englobe le processus dominant par lequel les ressources en eau sont affectées et le procédé qui peut le mieux être aménagé, pour limiter les impacts au-delà du site. Les auteurs revoient les processus courants, ainsi que les perceptions, de la déposition des sédiments provenant des forêts aménagées. Ils considèrent les composantes majeures des sédiments et la déposition par les eaux de surface, dans leurs relations spécifiques avec les activités d'exploitation forestière. Bien que les recherches conduites jusqu'ici aient mis l'accent sur la perte de sol, comme la composante majeure des impacts de l'exploitation, cette revue souligne à la fois les besoins et les bénéfices qui peuvent générer un progrès conceptuel, dans notre réflexion sur le dépôt des sédiments. Les auteurs proposent qu'en aménageant les sentiers de flux des sédiments ainsi que le patron de connectivité hydraulique qui s'en suit, on pourrait limiter les effets négatifs potentiels de la récolte forestière, sur la qualité des cours d'eau. On accorde une attention spéciale à l'interaction des chemins forestiers et du réseau de pistes, avec à la fois le flux et le dépôt des sédiments. Ceci conduit à une perception intégrée permettant de mieux aménager la récolte forestière, à la fois pour la durabilité du site, et la protection des ressources en eau, en aval. Mots clés : exploitation forestière, dépôt des sédiments, réseau routier, connectivité, pratiques optimales d'aménagement (BMPs).[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

States develop guidelines to protect and manage forest riparian resources. A review of 37 eastern states' forest riparian guidelines (e.g., BMPs, regulations) for timber harvesting revealed the primary focus is water quality protection adjacent to perennial and intermittent streams and lakes. A commonly recommended riparian management zone is 50-foot wide with 50–75 percent crown closure (or 50–75 ft2/acre of residual basal area), although the specific guidelines in each state vary tremendously. Additional values which increase the width of the riparian management zone are based on: (1) waterbody size, (2) slope of the ground adjacent to the waterbody, or (3) by incorporating slope effects with waterbody size or soil erodibility. While science cannot specify the management prescriptions needed to protect all riparian functions across all sites, understanding site-specific conditions can facilitate effective guideline implementation. There is a need for additional research within these areas to address a variety of questions. [ABSTRACT FROM AUTHOR]

An important aspect of a best management practices (BMP) program is providing credible information on the extent to which BMPs are being applied within the state. This paper, summarizing the responses of a survey to states about their BMP monitoring program, indicates nearly three of four states in the eastern U.S. have monitoring programs to determine if voluntary or mandatory forest practices are being applied. BMP compliance monitoring programs vary extensively among states in such areas as: the agency(s) responsible for undertaking the monitoring, the types of practices monitored, reasons for establishing the monitoring program, and the frequency and costs of compliance monitoring implementation. The survey found that information from compliance monitoring is used to modify forest practice rules or guidelines, redirect education and training programs, and inform policy makers and the general public of forest practice application rates. Major issues associated with implementing compliance monitoring programs as indicated by the survey include: specifying the types of information to be gathered, selecting harvest sites, accessing private property, determining monitoring responsibility, and reporting and using the information collected. [ABSTRACT FROM AUTHOR]

Forestry Best Management Practices (BMPs) were developed to protect water quality. In the eastern US, those BMPs were often expanded to include maintenance of site productivity. Generally, BMPs recommend the use of pre-harvest planning and careful design for construction of roads and other activities that expose bare soil, minimizing trafficking and areas of bare soil, maintaining streamside management zones, ensuring rapid revegetation following harvesting, minimizing soil disturbance, and ameliorating severe trafficking with site preparation. This review of peer-reviewed research from the past 20 years examined the effects of forest harvesting and site preparation on water quality and site productivity in the eastern US. The review was subdivided into areas having relatively similar physiography and land management (New England, Lake States, Appalachian Plateau, Ridge and Valley, Blue Ridge, Piedmont, Atlantic Coastal Plain, Gulf Coastal Plain, and Ouachitas-Ozarks). In general, data from steeper physiographic regions indicated that forest harvesting and site preparation can increase erosion, sediment and nutrient losses to streams. However, the quantities introduced into streams tended to be relatively low, generally below the values that are considered acceptable for alternative land uses. Also most research indicated that water quality recovers within two to five years following forest operation disturbances, particularly if BMPs are employed. Research from the less mountainous and often more poorly drained Lake States and Coastal Plain regions indicated that soil compaction and rutting may or may not cause site productivity effects, depending on soil types, natural ameliorative properties and site preparation. Overall, the research supports the forestry BMPs recommended in the eastern states. [ABSTRACT FROM AUTHOR]

We examined the impact of single-tree selective logging and fuel reduction burns on the abundance of hollow-nesting bird species at a regional scale in southeastern Queensland, Australia. Data were collected on species abundance and habitat structure of dry sclerophyll production forest at 36 sites with known logging and fire histories. Sixteen bird species were recorded with most being resident, territorial, obligate hollow nesters that used hollows that were either small (<10 cm diameter) or very large (>18 cm diameter). Species densities were typically low, but combinations of two forest management and three habitat structural variables influenced the abundances of eight bird species in different and sometimes conflicting ways. The results suggest that habitat tree management for biodiversity in production forests cannot depend upon habitat structural characteristics alone. Management histories appear to have independent influence (on some bird species) that are distinguishable from their impacts on habitat structure per se. Rather than managing to maximize species abundances to maintain biodiversity, we may be better off managing to avoid extinctions of populations by identifying thresholds of acceptable fluctuations in populations of not only hollow-nesting birds but other forest dependent wildlife relative to scientifically valid forest management and habitat structural surrogates. [ABSTRACT FROM AUTHOR]

The forest industry plays a major role in the economy of eastern Canada. The recreational fishery also represents an important source of revenue for this area. Therefore, there is concern over the potential economic effects and ecological impacts from logging operations on aquatic habitats. The present study deals with the comparison of streamflow between pre and post timber harvesting at Catamaran Brook (New Brunswick, Canada) to identify any potential changes to the hydrological regime. Studies were carried out on two sub-basins of Catamaran Brook, namely the Middle Reach (mid-basin) and the Upper Tributary 1. The harvested area at the Middle Reach represented 2.3% of this sub-basin while 23.4% of Upper Tributary 1 was harvested. It was noted that during both the calibration and timber harvesting phases, meteorological conditions (e.g. precipitation, runoff) contributed to relatively high natural variability. When studying changes on an annual and seasonal basis for the basin cut at 2.3% (i.e. Middle Reach) and using a control basin for comparison, no changes were detected to the annual water yield, seasonal runoff and streamflow timing between the calibration and timber harvesting phases. On a summer rainfall event basis, no changes were detected at the Middle Reach and the Upper Tributary 1 when studying relations between precipitation and stormflow (obtained through hydrograph separation). Alternatively, changes were detected in relations between peak flows and precipitation (p<0.05) at the Upper Tributary 1 when comparing the calibration and timber harvesting phases. Peak flows showed higher values following timber harvesting. No significant changes were observed between peak flows and precipitation at the Middle Reach.When comparative studies were carried out on peak flow and stormflow between sub-basins (using the Middle Reach as control for treatments vs. the most affected site, i.e. Upper Tributary 1), significant changes were detected in peak flow (p<0.05) between the calibration and timber harvesting phases at the Upper Tributary 1 only. Increased peak flows were observed at the Upper Tributary 1 compared to the Middle Reach following timber harvesting. It was concluded that for timber harvesting at Catamaran Brook, changes could only be detected on a summer storm event basis for the most affected site (Upper Tributary 1) and for peak flow only. [Copyright &y& Elsevier]

Summary The conservation of biological diversity is a fundamental consideration in the management of production forests in eastern Australia. Invertebrate communities make up the bulk of diversity in these forests, yet few studies have been conducted to determine what impact, if any, timber harvesting may have on their structure, dynamics or diversity. We report here on a space-for-time study conducted in an open eucalypt production forest in south-east Queensland that investigated the long-term effects of selective timber harvesting on the ground-active ant community. Over a notional 30–40 year logging cycle, there were significant changes in the composition of ant functional groups, no significant changes to ant abundance and a weak trend to reduced ant species richness as time since harvesting increased. However, when ant community composition was compared with logging history and other environmental variables using a range of statistical tests, only small changes in ant community composition were attributable to timber harvesting. This suggested that the ant community was at least partially controlled by factors other than management history or the environmental variables measured in this study. The diversity, abundance and organization of ant communities is therefore unlikely to be detrimentally affected by selective harvesting of timber, as currently practiced in state-owned forests in south-east Queensland. [ABSTRACT FROM AUTHOR]

Steep country harvesting has been identified as the main bottleneck to achieving greater profitability in the forestry sector of New Zealand and Australia. An improvement of efficiency, work safety and environmental sustainability should be realized by developing an advanced steep terrain timber harvesting system based on innovative Austrian technology. To identify the best suitable configuration of a cable yarder for steep terrain harvesting, user preferences based on an online survey (conjoint analysis) have been evaluated to answer the following questions: (1) What attributes of a new yarder design are most important to consumers? (2) Which criteria do stakeholders consider when selecting a cable yarder? (3) What are the weights representing the relative importance of criteria? Using eight specific design scenarios a fourth question, being which cable yarder concept is the best, was also answered. This case study shows that conjoint analyses is an effective tool to assess, rate and subsequently integrate design characteristics. Based on the results of the analysis, a cable yarder prototype will be manufactured in Austria and transferred to New Zealand for testing and demonstration. [ABSTRACT FROM AUTHOR]

Sequestration of carbon in forest ecosystems has been identified as an effective strategy to help mitigate the effects of global climate change. Prescribed burning and timber harvesting are two common, co‐occurring, forest management practices that may alter forest carbon pools. Prescribed burning for forest management, such as wildfire risk reduction, may shorten inter‐fire intervals and potentially reduce carbon stocks. Timber harvesting may further increase the susceptibility of forest carbon to losses in response to frequent burning regimes by redistributing carbon stocks from the live pools into the dead pools, causing mechanical damage to retained trees and shifting the demography of tree communities. We used a 27‐yr experiment in a temperate eucalypt forest to examine the effect of prescribed burning frequency and timber harvesting on aboveground carbon (AGC). Total AGC was reduced by ~23% on harvested plots when fire frequency increased from zero to seven fires, but was not affected by fire frequency on unharvested plots. The reduction in total AGC associated with increasing fire frequency on harvested plots was driven by declines in large coarse woody debris (≥10 cm diameter) and large trees (≥20 cm diameter). Small tree (<20 cm DBH) AGC increased with fire frequency on harvested plots, but decreased on unharvested plots. Carbon in dead standing trees decreased with increasing fire frequency on unharvested plots, but was unaffected on harvested plots. Small coarse woody debris (<10 cm diameter) was largely unaffected by fire frequency and harvesting. Total AGC on harvested plots was between 67% and 82% of that on unharvested plots, depending on burning treatment. Our results suggest that AGC in historically harvested forests may be susceptible to declines in response to increases in prescribed burning frequency. Consideration of historic harvesting will be important in understanding the effect of prescribed burning programs on forest carbon budgets. [ABSTRACT FROM AUTHOR]

Changing forest policies in both riparian and upland areas to help protect threatened and endangered species have contributed to the reduction of timber harvests in western Washington. The economic, biodiversity, and environmental impacts of these policy actions have been substantial. Policy simulations across 9.4 million acres of timberland show that relative to proactive management strategies, current habitat conservation and environmental programs (largely based on a reservation strategy) result in net present value reductions to forestland owners of $9.9 billion. Accompanying these asset value reductions are employment losses (sustained) of 30% and tax receipt losses of 26%. The policy simulations further demonstrate that proactive management will not decrease the long-term percentage of the upland landscape occupied by functionally old forests relative to the reservation strategy. In the riparian area, adoption of a reservation strategy actually decreases (by 29%) the percent of the landscape occupied by functionally old forests relative to a proactive management approach. These results illustrate the importance of proactively managing western Washington forests to provide maximum functionally old forest habitat for endangered upland animals (such as the northern spotted owl and the marbled murrelet) as well as riparian species. [ABSTRACT FROM AUTHOR]

Timber harvesting in British Columbia influences (a) forest hydrology; (b) fluvial geomorphology; (c) terrain stability; and (d) integrated watershed behavior. Impacts on forest hydrology are well understood and include increased average runoff, total water yield, increased storm runoff and advances in timing of floods. Stream channels and valley floors are impacted differently by fine sediment, coarse sediment and large woody debris transport. Terrain stability is influenced through gully and mass movement processes that are accelerated by timber harvesting. Impacts on integrated watershed behavior are assessed through disturbed sediment budgets and lake sediments. The Forest Practices Code (1995) is a significant step towards sustainable management of the land in so far as it attempts to minimize these geomorphic impacts of forest i B. C. [ABSTRACT FROM AUTHOR]

Foresters must have knowledge of understory vegetation responses to harvesting rehabilitation operations to manage competition effects ontree seedlings, protect species diversity, and reduce invasive weeds. Understory vegetation response to six post-harvest slash treatments, ranging from a high-intensity burn to mechanically chopped slash and untreated slash left in place, was documented for four eastern Washington mixed forest sites. We use species abundance graphs to show the relative effects of the six slash-treatment disturbances on vegetation dominance and diversity. Harvest substantially reduced understorycover, particularly among forbs. Shrub species persisted following harvest and in some treatments increased in cover. Slash treatments increased the abundance of weedy species that are not normally present in these forests. Treatments such as broadcast burning and pile/burn showed greater dominance by invader species. Overall, harvesting reduced species diversity but the response among slash treatments varied.After three growing seasons, species cover, richness, and diversity had no clear effect on seedling growth in slash-treatment plots. [ABSTRACT FROM AUTHOR]

The LANDIS model simulates ecological dynamics, including forest succession, disturbance, seed dispersal and establishment, fire and winddisturbance, and their interactions. We describe the addition to LANDIS of capabilities to simulate forest vegetation management, including harvest. Stands (groups of cells) are prioritized for harvest using one of four ranking algorithms that use criteria related to forest management objectives. Cells within a selected stand are harvested according to the species and age cohort removal rules specified in a prescription. These flexible removal rules allow simulation of a wide range of prescriptions such as prescribed burning, thinning, single-tree selection, and clear-cutting. We present a case study of the application of LANDIS to a managed watershed in the Missouri (U.S.A.) Ozark Mountains to illustrate the utility of this approach to simulate succession as a response to forest management and other disturbance. The different cutting practices produced differences in species and size-class composition, average patch sizes (for patches defined by forest type or by size class), and amount of forest edge across the landscape. The capabilities of LANDIS provide a modeling tool to investigate questions of how timber management changes forest composition and spatial pattern, providing insight into ecological response to forestmanagement. [ABSTRACT FROM AUTHOR]

Coarse woody debris (CWD) chronosequences were developed for managedand unmanaged red pine (Pinus resinosa Ait.) stands across the GreatLakes states. Throughout stand development, there is less CWD in managed than in unmanaged forests, and effects of management are strongest in young forests (0-30 years old). At stand initiation, CWD is 80%lower in managed than unmanaged forests, 20 200 versus 113 200 kg7ha-1, while at 90 years, CWD is 35% lower, 6600 versus 10 400 kg7ha-1. Timber management especially affects snags. In young managed forests, snag biomass is less than 1% of that in unmanaged forests, 150 versus 58 200 kg7ha-1, while log biomass is 80% lower, 5000 versus 22 800 kg7ha-1. This trend continues in mature forests (91-150 years old), where snag biomass is 75% lower in managed than in unmanaged forests, 1700 versus 6400 kg7ha-1. Management has relatively little impact on total log biomass of mature forests but increases the biomass of fresh logs nearly 10-fold, to 1400 versus 150 kg7ha-1. CWD in managed forests is highly variable, primarily related to thinning schedules in individual stands. [ABSTRACT FROM AUTHOR]

Abstract unavailable [ABSTRACT FROM AUTHOR]

Results from experimentally manipulating harvest intensity from 1 to6 trees ha-1 are reported for the Chimanes Forest, Bolivia. The area of vegetation damaged by logging was a quadratic increasing function of harvest intensity. This was because at higher harvest intensities, skidders used existing trails for log extraction, and trees tended to fall at least partially on existing gaps, so per tree damage declined with increasing harvest. The median distance of residual forest to the nearest gap after logging decreased from 24.9 m at 1tree ha-1, to 8.3 m at 6 trees ha-1. Both harvest mortality and total mortality (harvest plus damage to the residual stand) were quadratic increasing functions of harvest intensity when expressed in terms of basal area. Residual basal area damage was a very low because mortality was concentrated on the smaller size classes, which individually contribute little to total basal area. Of three commercial species surveyed, only the seedlings and saplings of Hura crepitans showed a significant positive relationship between relative growth rate and harvest intensity. Finally, tree species loss was relatively low and constant across a range of plot sizes and harvest intensities, but reductions in species diversity (H') depended on theintensity of harvest and plot size [ABSTRACT FROM AUTHOR]

The influence of both aerial and ground-based harvesting on functions of forested floodplains of low-order streams was studied during a two-year period. The study sites were associated with low-order, blackwater streams with infertile and primarily organic soils. Responses to harvesting were assessed in relation to water quality, denitrification, hydrology, regeneration, and decomposition. Water quality indices included nitrate, phosphate, total and dissolved solids, and biological oxygen demand (BOD). All were unaffected by harvesting with the exception of BOD which rose once to undesirable levels. Denitrification was highly variable and also showed no significant harvest effect.Hydrologic parameters included groundwater table depths which, unexpectedly, indicated lowered water tables within harvested areas duringthe first growing-season. Early regeneration responses were stronglylinked to harvest system with primarily seed-origin species favored by ground-based activity whereas sprout-origin species dominated on aerial system plots. Owing to inherent soil wetness, decomposition responded slowly to harvest disturbance. However, after one year, decomposition was more rapid on harvested plots than in undisturbed areas. [ABSTRACT FROM AUTHOR]