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The ecological impact of forest product harvesting is poorly understood despite the reliance of millions of impoverished households on forest resources. As birds are indicators of environmental change and essential for the function and regeneration of forest ecosystems, this study aimed to assess the response of bird species richness and functional diversity to unregulated forest product harvesting, to illuminate the impact of harvest disturbances on forest biodiversity. Five forest ecotypes in the Eastern Cape Province, South Africa were sampled by means of circular plots in which bird communities, habitat structure and harvest intensities of sub-canopy trees harvested for poles, canopy trees harvested for timber, and bark harvested for medicinal use, were recorded. Generalized linear models (GLMs) were used to assess the response of bird diversity to harvesting activities measured on a continuous scale, and forest ecotype. Correlations between feeding traits and environmental variables relating to habitat structure and harvest disturbances were investigated using RLQ and fourth-corner analysis to better understand which traits were sensitive to harvest disturbances. Results indicated that forest ecotype was an important driver of variation in species richness and functional diversity. Additionally, harvesting disturbances negatively affected two measures of functional diversity, while species richness and functional richness were unaffected by harvesting. Specifically, functional evenness was negatively affected by timber harvesting, while functional dispersion declined in response to pole and bark harvesting. Bird traits relating to feeding ecology (i.e. primary diet and foraging strategy) were associated with habitat structure and harvest disturbances, indicating that harvest activities affected community structure. Specifically, frugivores and granivores were negatively affected by pole and bark harvesting respectively, while omnivorous species were positively affected by these harvest activities. Conversely, timber harvesting negatively affected omnivores, and positively affected nectarivores. Bark and timber harvesting, which resulted in canopy gaps, negatively affected species which forage in the understory or on the forest floor, while pole harvesting, which reduced tree abundance but not canopy cover, negatively affected canopy-foraging species. These results suggest that current unregulated forest product harvesting in the Eastern Cape may negatively affect forest productivity and ecosystem functioning. Specifically, this is the first study to measure the effects of harvesting of poles and medicinal bark on the functional diversity of avian forest communities.

1. Forest landscape restoration (FLR) has gained momentum globally and guidance is needed to identify those species, sites and planting methods that increase restoration success. Incorporating native Non-Timber Forest Product (NTFP) species in FLR approaches provides an opportunity to simultaneously deliver ecological and economic benefits. The Brazil nut tree is one of the most valuable Amazonian NTFP species and could fulfil a cornerstone role in Amazon FLR. However, the factors defining establishment success within Brazil nut restoration activities remain unknown. 2. Here, we evaluate the effect of management practices, restoration site (pastures, agroforestry, secondary forest and canopy gaps in old growth forest) and environmental conditions on the establishment success (tree growth, survival and fruit production) of Brazil nut restoration projects implemented by smallholders in the Peruvian Amazon. We performed a field study at 25 restoration sites of 1–38 years in age, where we conducted measurements on 481 trees and interviewed 21 smallholders. We used mixed effect models to identify drivers of performance. 3. Twenty years after planting, diameter growth in secondary forests was 38%, 34%, and 24% higher than in canopy gaps, pastures, and agroforestry sites, respectively. Survival rate was similar for trees planted in pastures and secondary forests, but 15–20% higher there than trees planted in agroforestry sites, and 7–12% higher than in canopy gaps. Fruit production was 262% higher for reproductive trees in secondary forest sites compared to pastures, but production probability did not differ between restoration sites. These results show that secondary forests are the most suitable sites for planting Brazil nut trees. 4. In addition to restoration site effects, we also found significant effects of management practices. Survival rate increased with application of fire for clearing and weeding and economic investments and decreased with potentially inefficient herbivore protection. Fruit production was lower for trees planted further away from smallholders’ homes. These results show that smallholders’ management has a substantial effect on establishment success. 5. Our findings suggest a significant importance of post-planting maintenance of trees to increase success of FLR projects. Further, our study shows that evaluation of past restoration activities can guide future forest restoration in tropical landscapes., Forest Ecology and Management, 498, ISSN:0378-1127, ISSN:1872-7042

The low natural regeneration of the Brazil nut (Bertholletia excelsa) in the Madre de Dios region of Peru is a major concern for the conservation and sustainable use of this species which sustains one of the cornerstone non-timber forest product economies in Amazonia. The Brazil nut is a gap-dependent, long-lived pioneer species that has been shown to regenerate more effectively in fallows than in mature forests. Aside from light and nutrient availability, recruitment success of the species might also be influenced by conspecific negative distance-dependent (CNDD) processes as shown for a myriad of other tropical tree species, but to date has not been studied in the Brazil nut. We measured Brazil nut recruitment in forty 150 × 10 m2 transects (totaling 6 ha), proportionally laid out in mature forest and fallow land. We found a higher likelihood of regeneration in fallows than in mature forest, which was mainly due to more successful transitioning from seedlings to saplings in fallows. Recruitment rates in fallows increased with the number of fire events occurring over the past 12 years, largely owing to the accumulation of resprouting individuals, but this positive correlation was only observed up to three fire events. We observed CNDD recruitment of the Brazil nut in fallows but not in mature forest, suggesting that pests and diseases might also condition Brazil nut recruitment. Our findings suggest that a better management of fallow land and more controlled use of fire in neighboring land uses could be a cost-effective manner to create Brazil nut rich forests through natural regeneration. On the other hand, the absence of high density Brazil nut stands in mature forests in Madre de Dios might mean that the impact of ancient humans there has been more limited than in other Amazonian regions.

Forests not only provide forest products to meet people’s demands, but also sequester enough carbon to offset more than 11% of anthropogenic CO2 release in the United States. An accurate estimate of forest carbon sequestration over different forest and forest product combinations requires the species-specific and site-specific allometric biomass equations for trees and understory vegetation at particular forest developmental stages. Here, we constructed the above- and below-ground allometric equations by harvesting 108 20-year-old ponderosa pine (Pinus ponderosa) trees grown under four different silvicultural treatments (four combinations of with and without competing vegetation control (H) and fertilization (F): C = control with no vegetation control and no fertilization, H, F, and HF) at three diverse site conditions in northern California. We found that the logarithmic regressions provided superior estimations of biomass for total, aboveground, bole, coarse roots, branches, and foliage compared to simple or scaled power-law fits. Treatment effect in allometric equations was generally lacking but site effect was significant, suggesting site specific allometric relations exist. With the best allometric equations, we estimated the biomass and carbon for each plot among treatments and sites. In addition, understory woody plant biomass was also measured with fixed area subplots. Results show significantly more total carbon sequestration at the high-quality sites with 113.1–162.5 Mg ha−1 than the lower ones with 85.8–105.9 Mg ha−1 at the intermediate site and 29.3–70.4 Mg ha−1 at the poorest site, respectively. The range of carbon stocks indicates the treatment differences at each site, with the largest effect (240%) at the poorest site and similar at other two sites (~130%). If planted trees only were considered, a trend among sites exists with 93.4 – 149.3 Mg ha−1 at the richest site, 26.2–88.1 Mg ha−1 at the intermediate site, and 17.1–64.2 Mg ha−1 at the poorest site, respectively. Therefore, if we manage forests for carbon or forest products, intensive management practices will substantially enhance plantation productivity and stand development while site quality cannot be changed.

Changes in ownership and forest product use patterns have incentivized growing loblolly pine (Pinus taeda L.) for chip-and-saw and sawtimber in shorter rotations in the southeastern United States. These management objectives can be accomplished by relatively low stand densities and moving fast-growing genotypes from the Atlantic Coastal Plain to other regions of the loblolly pine range, but wood quality concerns accompany these silvicultural options. In three trials in the Western Gulf region of the mid-South United States, effects of stand density management options on key wood properties (specific gravity, corewood (juvenile wood) diameter, corewood proportion, latewood proportion, corewood:outerwood (juvenile wood:mature wood) transition age as determined using specific gravity) were tested. At one site, clearwood modulus of elasticity (MOE) and modulus of rupture (MOR) were measured. Genotypes of Atlantic Coastal Plain and Western Gulf origin were also tested at two sites. In a trial in which stand density was managed at diverse levels through sequential thinning, beginning at precommercial size, only a regime that was commercially thinned to half its density two times from 297 TPH at age 7 to 62 TPH by age 41 had significant reductions in MOE, MOR, and specific gravity. Corewood diameter increased with decreasing planting density at two sites at the northwestern edge of the loblolly pine range, but corewood proportion declined with decreasing planting density due to greater diameter growth and earlier transition from corewood to outerwood. Specific gravity differences among planting densities was site-specific, with no differences at the more well-drained site. Latewood proportion, which was greater at higher planting densities, was more strongly correlated with specific gravity differences among planting densities. A planting density between 1075 and 1680 TPH would likely be optimum for these site conditions for balancing tree volume growth with minimizing reductions in specific gravity associated with reduced latewood proportion and larger corewood size. The Atlantic Coastal Plain genotype retained its tendencies to transition to outerwood earlier and have greater latewood proportions relative to a local genotype when planted at these Western Gulf sites, and its specific gravity was similar to that of the local genotype. Together these trials suggest that forest managers have flexibility in managing loblolly pine stand density without altering wood properties. Furthermore, these results provide some evidence that moving genotypes may not carry a risk of reduced wood specific gravity.

Tropical rainforests harbor a high diversity of tree species, offering a potentially rich array of timber (TFP) and non-timber (NTFP) forest products. The supply of such products has been commonly evaluated at the local (plot) scale; however, little is known about how their availability and diversity change at the landscape scale, particularly in heterogeneous environments. This information is critical in designing landscape forest management programs. Here, we assess the extent to which the frequency, abundance, diversity, composition and productivity (aboveground biomass) of tree assemblages with potential forest products (PFPs) change across three landscape units (LUs) that differ in soil and topographic conditions. The study was carried out in a well-conserved old-growth tropical rainforest in southeastern Mexico. Three plots (0.5 ha each) were established per LU, in which all trees ≥ 10 cm were inventoried, taxonomically identified and assigned to eight forest product categories. General linear models, multiple regression and ordination analysis (CCA) were used to assess structural and compositional changes in the tree assemblages supplying different PFPs among LUs and along soil physicochemical gradients. More than half (94 species, 57%) of the total number of identified species (165) had one or more PFPs, mostly related to timber products. Ordination analysis showed that the abundance of species with different PFPs has a heterogeneous distribution among LUs, mostly related to changes in soil nitrogen, pH and aluminum saturation. Variation among LUs in terms of tree biomass was strongly driven by soil available phosphorus and soil physiological depth. Each LU had a different potential to provide forest products, producing a diverse mosaic of PFPs within the landscape. Decisions concerning sustainable forest management should consider such variability in the availability and diversity of forest products across landscapes, as well as the environmental factors that govern this spatial variation.

Integration of the mitigation and adaptation roles of forests is important in addressing climate change issues. Community forests (CFs) have capacity to contribute in both roles as local communities are collectively working to improve forests and to fulfil their own basic forest product needs. Nowadays, an incentive mechanism for Reduced Emissions from Deforestation and forest Degradation, conservation of forests, sustainable management of forests and enhancement of carbon stocks in forests (REDD+) is emerging and already has received considerable attention in achieving climate change mitigation whereas there has been little analysis of its potential contribution to adaptation objectives, particularly at the community level. Therefore the overarching goal of this study was to analyse CFs from a mitigation and adaptation perspective. This study assesses 105 CFs covering a range of forest types managed by socially diverse communities of Nepal. Two point carbon data (2010 and 2013) was analysed to investigate differences in carbon stocks in these forests following the introduction of a REDD+ pilot program in Nepal. Similarly, a document review and focused group discussions were organised to evaluate the livelihood support and adaptation potential of pilot REDD+ CFs. This study found that community forest user groups (CFUGs) have increased forest carbon stocks and that the pilot REDD+ projects are also delivering livelihood benefits which ultimately will help adaptation to adverse climatic conditions. However, the motivation for communities to realise REDD+ carbon incentives may reduce the food supplement capacity of forests by limiting vegetation diversity.

Pine trees produce large amounts of oleoresin to defend against biotic threats. Resin is highly costly to produce and investment in its production must be accurately optimized in relation to allocation to other life functions such growth. As a result of these costs, resin production is highly variable both genetically (among and within species) and plastically (across temporal and spatial environmental heterogeneity). The relative contribution of these sources of variation is, however, far from being completely understood. Besides being a main defensive mechanism, pine resin is also a valuable non-timber forest product that is regaining attention as a renewable resource for different industrial sectors. Improving our knowledge on the main drivers of resin production is vital to fine-tune resin-tapping management, especially in regions with little tradition in resin-tapping such are the Atlantic areas of the Iberian Peninsula. Here, we assessed resin flow and growth in a network of seven Maritime pine (Pinus pinaster) provenance tests established in North West Spain to explore the within species variation in resin flow, the plasticity of resin flow across sites and across the season and the (phenotypic and genotypic) relationships between resin flow and tree growth. Resin flow was assessed in three contrasting Maritime pine populations at three times within the season using a micro-tapping procedure that predicts well the resin yield potential for exploitation purposes. Results supported the theoretical predictions as resin flow significantly varied among populations, with populations from more favorable environmental conditions producing less resin than those from harsher conditions. Resin flow was positively correlated with tree size at the phenotypic level. However, the genetically-based relationship between growth potential and resin flow was markedly negative. Fast growing populations produced less resin than slow growing origins. Resin flow was also highly plastic across sites and across seasons, with resin flow consistently increasing towards the end of the growing season. Temperature and water deficit immediately before sampling emerged as main drivers of the observed variation in resin flow across sites and seasons. Results are valuable to understand the extremely large variation in defensive investment on resin-based defenses in conifer species, to model the potential of Atlantic Maritime pine forest for resin tapping, and to fine-tune the resin-tapping management of these forests.

Assessment of forest carbon storage dynamics requires a variety of techniques including simulation models. We developed a hybrid model to assess the effects of silvicultural management systems on carbon (C) budgets in longleaf pine (Pinus palustris Mill.) plantations in the southeastern U.S. To simulate in situ C pools, the model integrates a growth and yield model with species-specific allometric and biometric equations and explicitly accounts for the impacts of both thinning and prescribed fire. To estimate the ex situ C pool, the model used the outputs of merchantable products from the growth and yield model with current values of forest product conversion efficiencies and forest product decay rates. The model also accounts for C emissions due to transportation and silvicultural activities. Site productivity (site quality) was the major factor controlling stand C density followed by rotation length. Thinning reduced C sequestration, as the slow growth rate of longleaf pine reduced the potential of C sequestration in forest products. Prescribed burning reduced average C stock by about 16–19%, with the majority of the reduction in the forest floor. In a comparison of longleaf pine C dynamics with slash pine (Pinus elliottii Engelm.), both species reached a similar average C stock at age 75 years, but when averaged across the whole rotation, slash pine sequestered more C. Nevertheless, for medium quality sites, C sequestration was similar between thinned 75-year rotation longleaf pine and unthinned 25-year rotation slash pine. This longleaf pine plantation C sequestration model, based on empirical and biological relationships, provides an important new tool for developing testable research hypotheses, estimating C stocks for regional assessments or C credit verification, and for guiding future longleaf pine management.

Evaluations of the effects of non-timber forest product (NTFP) extractive industries by traditional communities have focused on local effects, but effective conservation of species often requires evaluation at wider scales that can only be efficiently undertaken with the use of remote sensing. Brazil nut (Bertholletia excelsa seed) is one of the most important NTFP in the Amazon basin and has received considerable attention from researchers aiming to guarantee its sustainability. However, most studies evaluating the impacts of B. excelsa seed harvesting investigated only effects in harvested sites, and did not consider B. excelsa availability in the landscape, or patterns of harvesting at broader scales, which are critical to evaluate the viability of extraction and plan management practices. We used high-resolution satellite images associated with ground truthing, participative mapping with harvesters and harvest records, to evaluate abundance of B. excelsa in the territories of three Kayapo indigenous communities in southeastern Amazonia. This allowed us to obtain conservative estimates of the proportion of Brazil nut harvested by the Kayapo at scales appropriate to evaluate effects on stocks in the landscape and in harvested groves. B. excelsa groves are abundant in the Kayapo lands, but only about 30% of them are harvested. In recent years, the villagers have harvested from 7.2% to 43% of the seeds produced in harvested groves. These represent only 2.5–12.7% of total seeds estimated to have been produced within the Brazil nut-collection territories of those Kayapo villages. Our results show that the Kayapo have undertaken non-intensive Brazil nut harvesting at local and especially at landscape scales, which suggests that B. excelsa is currently not threatened by harvesting in the region and that there is still potential to expand commercial production in at least one of the sites. The application of similar multi-scale approaches in other sites and for other non-timber forest products would provide important information to evaluate their long term conservation, subsidize the development of management plans and help to guarantee the livelihoods of traditional communities.

Non-timber forest products, particularly herbaceous understory plants, support a multi-billion dollar industry and are extracted from forests worldwide for their therapeutic value. Tens of thousands of kilograms of rhizomes and roots of Actaea racemosa L., a native Appalachian forest perennial, are harvested every year and used for the treatment of menopausal conditions. Sustainable management of this and other wild-harvested non-timber forest products requires the ability to effectively and reliably inventory marketable plant components. However, few methods exist to estimate below-ground biomass (rhizomes and roots) based on above-ground metrics. To estimate the relationship of above-ground vegetation components to below-ground biomass, data from a long-term sustainable harvest study of A. racemosa was used to develop a predictive model for rhizome mass. Over 1000 plants were extracted from two sites in the Central Appalachian Mountains of Virginia. Measurements of plant height and canopy dimensions were matched with corresponding green weights of rhizomes and roots. A multi-staged process was used to fit a mixed effects model. A random effects structure was selected using Akaike’s Information Criterion, while the fixed effects structure was simplified through backward selection using likelihood ratio tests. Over 500 plants were harvested from three neighboring sites to evaluate the effectiveness of the model in predicting below-ground biomass based on above-ground metrics. The relationships between above and below-ground biomass of plants from the sustainability study sites and the validation study sites were similar, indicating effectiveness of the model. Predicted values for the validation data were, on average, slightly larger than the observed values, indicating a small bias. The 95% prediction intervals computed from the model, however, covered the true values more than 95% of the time. This study demonstrates that estimating marketable rhizome biomass of native medicinal plants is feasible at a stand level. The model will serve as a valuable tool for inventorying forest products, allowing estimation of below-ground biomass based on above-ground metrics. Use of this tool will aid in developing effective inventory and management strategies for wild-harvested medicinal plants. Adaptation of this model to other species will encourage efforts toward sustainable use of non-timber forest products worldwide.

Euterpe edulis is an endangered species due to palm heart overharvesting, the most important non-timber forest product of the Brazilian Atlantic Forest, and fruit exploitation has been introduced as a low impacting alternative. However, E. edulis is a keystone species for frugivores birds, and even the impact of fruit exploitation needs to be better investigated. Since this species occurs over contrasting habitats, the establishment of site-specific standards and limits for exploitation may also be essential to achieve truly sustainable management. In this context, we sought to investigate how soil chemical composition would potentially affect E. edulis (Arecaceae) palm heart and fruit exploitation considering current standards of management. We studied natural populations found in Restinga Forest and Atlantic Rainforest remnants established within Natural Reserves of Sao Paulo State, SE Brazil, where 10.24 ha permanent plots, composed of a grid of 256 subplots (20 m 20 m), were located. In each of these subplots, we evaluated soil chemical composition and diameter at breast height of E. edulis individuals. Additionally, we evaluated fruit yield in 2008 and 2009 in 20 individuals per year. The Atlantic Rainforest population had a much higher proportion of larger diameter individuals than the population from the Restinga Forest, as a result of habitat-mediated effects, especially those related to soil. Sodium and potassium concentration in Restinga Forest soils, which have strong negative and positive effect on palm growth, respectively, played a key role in determining those differences. Overall, the number of fruits that could be exploited in the Atlantic Rainforest was four times higher than in Restinga Forest. If current rules for palm heart and fruit harvesting were followed without any restriction to different habitats, Restinga Forest populations are under severe threat, as this study shows that they are not suitable for sustainable management of both fruits and palm heart. Hence, a habitat-specific approach of sustainable management is needed for this species in order to respect the demographic and ecological dynamics of each population to be managed. These findings suggest that any effort to create general management standards of low impacting harvesting may be unsuccessful if the species of interest occur over a wide range of ecosystems. 2012 Elsevier B.V. All rights reserved.

The “Proyecto Pavo” is a project dedicated to the conservation of the Ocellated Turkey (Meleagris ocellata) through sustainable use of the species in multiple-use, community-managed forest concessions of the Maya Biosphere Reserve in Peten, Guatemala. Since 2000, the project has conducted selective turkey harvests, performed related research, and promoted the conservation benefits of managed sport hunting for this species. Field activities of the project feature providing high-quality Ocellated Turkey hunts to sport hunter clients. Participating concessions benefit directly from harvest revenues of a resource that was not previously exploited commercially and indirectly from affiliated project activities. The project began operations in a single concession on an experimental basis and evolved into a commercial enterprise operating in multiple concession units. The project has overcome numerous development and operational challenges, including compatibility issues with timber and NTFP extraction. Under proper circumstances, carefully designed sport hunting programs can offer profitable and sustainable forest product diversification alternatives that are highly compatible with tropical multiple-use management and forest conservation objectives.

Developing sustainable extractive industries in otherwise intact tropical forest regions requires a sound understanding of the production potential of key resource populations. The oleoresin extracted from Copaifera trees is an economically important non-timber forest product harvested throughout the lowland Amazon basin. We studied oleoresin extraction from four species of Copaifera trees with known harvest histories within two contiguous extractive reserves in western Brazilian Amazonia. We conducted a large-scale experimental harvest of 179 previously unharvested Copaifera trees, in both seasonally flooded (varzea) and adjacent unflooded (terra firme) forests. The likelihood of trees yielding any oleoresin was principally determined by their species identity: C. multijuga was the only species to regularly yield oleoresin (70% of trees). Yield volumes varied both amongst species and forest types: C. multijuga (restricted to terra firme forest) had the highest mean yield of 505 ml, whilst C. guyanensis produced higher volumes of oleoresin in varzea (139 ml) than terra firme (15 ml) forest. Intraspecific differences were driven mainly by tree size. To assess extraction sustainability, we reharvested a sample of C. multijuga trees and compared the oleoresin production of 24 conspecific trees that had been initially harvested one year previously with that of 17 trees initially harvested three years previously. Reharvested trees produced just 35% of the oleoresin volume compared to that when originally drilled, but this response was not affected by the time interval between consecutive harvests. We demonstrate that, within a population of Copaifera, both morphological and environmental factors restrict total productivity; consideration of these factors should inform sustainable management practises. We additionally raise methodological considerations that may improve the comparability of studies.

In this study we analyzed the effect of silviculture on carbon (C) budgets in Pinus elliottii (slash pine) plantations on the southeastern U.S. Coastal Plain. We developed a hybrid model that integrates a widely used growth and yield model for slash pine with allometric and biometric equations determined for long-term C exchange studies to simulate in situ C pools. The model used current values of forest product conversion efficiencies and forest product decay rates to calculate ex situ C pool. The model was validated from a variety of sources, accurately simulating C estimates based on multiple measurement techniques and sites. Site productivity was the major factor driving C sequestration in slash pine stands. On high productivity sites, silvicultural schemes that promote sawtimber-type products are more suitable for increasing C storage (even not taking in account the consequent economical revenues associated with sawtimber production). When rotation length was increased from 22 to 35 years on unthinned and thinned stands, respectively, we estimated net increments of 26 and 20 MgC ha −1 in average C stock of the first five rotations. Even though in situ C pool in slash pine accounts for most of this net increment, C in sawtimber products increased from 8 and 14 to 23 and 24 MgC ha −1 , on unthinned and thinned stands, respectively. Thinning effects on net C stock depended on intensity and timing of intervention, mainly due to changes in diameter classes that promote higher proportion of long-lived products. Emissions associated with silvicultural activities, including transportation of logs to the mill, are small compared to the magnitude of net C sequestration, accounting for between 2.2 and 2.3% of gross C stock. This slash pine plantation C sequestration model, based on empirical and biological relationships, is appropriate for use in regional C stock assessments or for C credit verification.

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

We discuss the extent of compatibility of timber and non-timber forest product (NTFP) extraction in two neotropical localities from biophysical, social, and institutional perspectives: the community concession forests of the Peten, Guatemala, and extractivist communities in northern Bolivia. In both localities, timber is harvested via reduced-impact logging (RIL) practices. In Guatemala, the main NTFP extracted is foliage from the understory xate palm (Chamaedorea spp.); in northern Bolivia, the fruits of the Brazil nut tree (Bertholletia excelsa). The Guatemalan case suggests a relatively high degree of compatibility due to low timber harvesting intensities, coupled with temporal, spatial, and social segregation of xate extraction in a well-defined land tenure system. In northern Bolivia, forest management regulations pay little attention to NTFPs and land tenure issues and related conflict complicate efforts to limit timber harvesting impacts on Brazil nut trees. The introduction of timber management plans overlain on customary property rights systems in which the extraction of Brazil nut is organized could undercut its management system. The two case studies suggest that specific legislative, education, and project interventions may help to promote the compatibility of timber and NTFP extraction and management. These include formal training of foresters on NTFP ecology and management while taking into account the perspectives of multiple stakeholders in the design of management plans. Tropical forest users, research managers, and policy makers will also better understand the need for integrated management of timber and NTFPs, if the trade-offs and potential economic benefits from NTFP extraction are clarified.

Nontimber forest product harvesting in the Pacific Northwest is neither a new activity nor a disappearing relic of the pre-industrial era. Though the emphasis may have shifted from subsistence to commercial and recreational pursuits, harvesting and harvesters of wild species are still widespread throughout the region. Hundreds of businesses and thousands of harvesters earn part or all of their income from the harvests. Every year thousands of pounds and hundreds of nontimber forest products valued in the hundreds of millions of dollars are harvested from regional public and private forests. This harvesting of a large diversity of species represents a considerable subset of the overall terrestrial biodiversity in Pacific Northwest forests. Despite widespread extraction, little investment in research, planning, or basic inventorying and monitoring has been done on nontimber forest products. Without better information, land managers will be increasingly unable to make informed decisions on how to manage nontimber forest product biodiversity sustainably as demand for products increases.

Field studies in Acre, Brazil assessed logging impacts of a certified community timber management project. The main objectives of the study were: (1) to determine if damage incidence to future crop trees (FCTs; ≥20 cm diameter at breast height (dbh)) differs between (a) forest with and without bamboo (Guadua spp.), and (b) trees with and without lianas; (2) to what extent harvesting can be conducted more intensely (m3ha−1), without incurring greater FCT damage; and (3) to what extent marking diminishes FCT damage. Full inventories of FCTs of 50 commercial species complexes were conducted before and after logging in 50 m-radius zones of impact around each designated harvest tree in three 10 ha (200 m × 500 m) logging blocks. We also mapped all forested areas potentially influenced by logging, including skid trails, log landings and felling gaps, throughout the 30 ha logged. More than 28% of the forest area was disturbed by logging, with 12.1% in skid trails and 16.8% in gap clearings, indicating that the forest gap mosaic can be significantly altered even when reduced-impact logging guidelines are followed. Overall, 15% of FCTs inventoried were damaged. Damage rates were not significantly reduced by marking treatment, location in bamboo-dominated forest, or liana load on FCT damage. Harvest intensity did not influence the probability of FCT damage. For future studies, it would be prudent to address impacts of timber extraction on other livelihood activities, such as non-timber forest product collection, particularly in such regions as the Brazilian Amazon, where many communities are attempting to integrate a suite of income-generating activities.

Studies of land-use/land cover change are an important means for examining the viability of community-based programs for forest conservation, although an analysis of the social processes influencing land-use decisions is necessary to understand the factors leading to different conservation outcomes. In this paper, we demonstrate that an analysis of locally recognized land-use rules and regulations embedded in local institutions can inform remote-sensing approaches by helping: (1) to elucidate some of the local perceptions, criteria and interactions with outside agencies that drive conservation actions and (2) to better interpret the spatial patterns of land-use change and forest conservation revealed by remote-sensing data. Based on a case study of a forest ejido from the Maya Zone of Quintana Roo, Mexico, we evaluate changes in forest cover and in local land-use regulations before and after the initiation in the mid-1980s of a community forestry program, the Plan Piloto Forestal (PPF). Methods included development of a time series of land cover maps based on LANDSAT imagery from 1976, 1988, 1991, 1997 and 2000, as well as interviews and participant observation with local farmers and community leaders. Results indicate a high degree of forest conservation on community lands with net rates of forest loss of 0.6‐0.7%/year. Locally recognized conservation regulations included a number of forest reserves as well as regulations which protect specific forest types, resulting from both local initiatives and interventions of external agencies. These initiatives included but were not limited to the PPF, highlighting the importance of evaluating community-based conservation programs within a broader historical context. Conservation regulations protecting an important commercial non-timber forest product (Manilkara zapota) pre-dated the PPF and may have facilitated its implementation. In the most accessible agricultural areas, the only mature forest patches were customary forest reserves and an area regenerated from secondary forests, protected due to enrichment plantings of commercial timbers. Recognition of local Maya terminology used to distinguish forest types was crucial for proper interpretation of local land-use regulations, which revealed that less-valued forest types may not be adequately protected on community lands. We suggest that future research should examine the significance of the less-valued forest types for global biodiversity conservation. In addition careful consideration of the historical antecedents and community institutions which may have facilitated the implementation of the Plan Piloto Forestal will be important for the successful application of this model of community forestry to other socio-economic and cultural contexts. # 2005 Elsevier B.V. All rights reserved.

Stand-level forest management prescriptions for federal forests in the interior northwest (USA) have changed emphasis in the past decade from being influenced by economic criteria to being influenced by ecological criteria. The design of forest management prescriptions that maintain stand density levels within a target range is now preferred over the design of prescriptions that maximize net present value. We describe a stand-level optimization process for developing efficient management regimes that uses dynamic programming and a region-limited search strategy. The process develops management regimes by penalizing deviations from a preferred range of stand density. Operational considerations, such as minimum harvest levels, can be important, and are considered as constraints in this modeling process. The timing of harvests is such that entries are only permitted when a minimum harvest can be obtained, when a minimum residual basal area can be maintained, and when harvests are limited to trees with a certain diameter range. Lists of residual, harvested, and dead tree records are available for each decade of the optimal regime. These records of information can facilitate further forest product or habitat suitability analysis associated with forest policy analyses.

Geonoma orbignyana is a common understory palm, whose leaves are used as foliage in Colombia. This palm has been used for more than 30 years; but there is no information about its life history or conservation status. Our objective was to characterize the life history of this palm and population dynamics of a natural population as a first step to assess the effect of leaf harvesting. More than 1600 palms were monitored from June 1999 to March 2000; we measured growth, mortality, and reproductive success. Population dynamics were evaluated using a Lefkovitch matrix model, and elasticity analysis. Results indicate that G. orbignyana grows at a rate of 1.98 ± 0.047 leaves/year, the palm has a long lifespan, and growth and reproduction are related to light conditions in the forest. The density of this palm is high (108–311 palms/100 m2), which is explained in part by its capacity to continue growing after damage, and to respond to the frequent gap formation in the forest. The population is growing (λ = 1.074, CI = [1.046–1.099]). Survival transitions account for 77% of population growth, a value that is higher compared to other understory plants. Because of the high density, the recovery capacity of these palms, and the correlations found between individual and population performances with forest dynamics, we hypothesize that G. orbignyana behaves as an opportunistic species taking advantage of forest gaps. This palm is a promising non-timber forest product (NTFP) with a high profile for further exploitation, although we recommend that harvesting regimens should consider time of recovery and forest dynamics. Without these considerations mortality could increase in all classes, which will compromise population persistence. Further studies should accurately estimate the recovery time after defoliation as well as to characterize forest dynamics identifying its most important features for population growth.

This study follows the 20-year period of a forestry innovation—the share-holding integrated forestry tenure (SHIFT) system—its adoption, diffusion, adaptation and transformation in Sanming Prefecture, Fujian Province of the People’s Republic of China. Our research suggests that the adoption of this innovation in forest management institutions and technologies tends to follow the familiar “s” curve. However, the prevailing patterns in the social, economic, cultural, and biophysical environments that encouraged the adoption have changed overtime as it moved to an adaptive phase. The need for flexibility and resiliency in forestry strategies is necessary if the goals and objectives promised by innovation are to be sustained. SHIFT was initiated as an innovative rural development program of “private-like” forest management, where villagers became shareholders in the community forestry operation and obtained employment through a system of tenure contracts. SHIFT has proven to be an effective system for the regeneration and protection of Sanming’s forests. Changing conditions in the social, economic, cultural, and biophysical environments of Sanming have undermined the value of the shareholding system and the benefit distribution of tenure contracts. However, villager confidence in the SHIFT system remains positive as direct dividend benefits have been replaced by those accrued through the harvest of non-timber forest products and a new household tenure contract to supply individual household forest product needs.

The harvesting of non-timber forest products has been proposed as an alternative to timber harvesting that can increase rural income while having a reduced impact on forest structure. However, surprisingly little is known about the biological consequences of harvesting these products. We conducted a 3-year experiment in which we simulated the stem harvesting of the Amazonian plant Ischnosiphon polyphyllus, which is used by traditional and indigenous populations in the Amazon for the construction of baskets, mats, and other handicrafts used in manioc cultivation. We found that plant mortality is limited in all except the most extreme harvesting treatments. However, we also found that plants recuperate extremely slowly from experimental harvesting. These results suggest that current harvesting strategies may not be conservative enough to ensure long-term population survival.

In order to evaluate the extractive use potential of Desmoncus orthacanthos , various matrix models were employed to assess population structure and dynamics. To this end, populations of this liana palm were investigated in southern Quintana Roo, Mexico, at two localities showing contrasting fragmentation levels arising from different land use regimes. In one case continuous forest (CF) are maintained under forestry management, while in the other (fragmented forest, FF) isolated forest patches remain inside of a matrix of crop and livestock lands. Three forest conditions: mature forest (MF), young forest (YF) and forest edge (FE) were nested in each fragmentation level. Results showed that more plants were encountered under FF situations than under CF conditions; however, no differences were noted in exploitable shoots (i.e., total numbers and lengths) when both were compared. Under forest conditions, number and length of exploitable shoots did not differ between FE and MF populations, however these values were smallest in YF populations. Intrinsic population growth rates ( λ ) were lower under FF than under CF, as reflected by periodic matrix values of 0.964 and 1.594, respectively. With respect to forest conditions, λ for FE> λ for YF> λ for MF and periodic matrix values were 1.441, 1.193 and 1.075, respectively. Elasticity analyses for annual matrices showed that the demographic process having most influence on variations in λ was (periodic matrix values) permanence (43–63%), followed by growth and retrogression (15–22% and 14–23%, respectively); fecundity had the lowest influence in changes of λ -values (8–13%). Analyses of the simulated extraction of shoots ≥5 m suggested that FE and CF populations might support harvest rates of 40% per year, since λ >1; however, simulation of harvest rates as low as 20% in other populations always resulted in λ λ , especially for FE populations; simulations combining shoot extraction with the addition of juveniles suggested that high levels of harvest may be possible, even while maintaining λ >1; but only if sound forest management is practiced and agricultural fires are restricted. This work showed the value of matrix models for analyzing populations dynamics in establishing sustainable use strategies for D. orthacanthos as opposed to static evaluation of population numbers.

Aerial roots from hemiepiphytic Heteropsis (Araceae) vines have long been used in Amazonia as a strong flexible material in construction and making handicrafts. Commercial demand for this product known in Brazil as “titica” has increased in recent decades for making wicker furniture. We conducted inventories, harvests and experimental root cutting in the Alto Rio Guama Indigenous Reserve in the eastern Brazilian Amazon to investigate several aspects of titica ecology, root biology, and harvest impact to estimate root harvest potential in a range of intact and disturbed forest areas. The average density of host trees with titica roots in relatively undisturbed upland “terra firme” plots with light to moderate forest use was 371 trees/ha with 115 of these having commercially harvestable roots. These areas had an average of 0.9 commercially harvestable roots and 2.4 non-harvestable roots per host tree generating a titica root density of 1332 roots/ha with 26% of these being commercially harvestable. Titica plants did not show a positive preference for particular types of host trees, but the number of titica roots per host tree did increase with host tree size. The vines were virtually absent from forest areas subject to periodic flooding, a common palm tree found near small streams, and on pioneer tree species in patches of secondary forest recovering from a fire that occurred almost 20 years ago. Experimental cutting of mature titica roots showed that harvesting can have a severe impact on root survival. In the two treatments, where at least half of mature titica roots per host tree were cut 4 m above the ground, an average of 63% cut roots died and only 16% showed some regrowth after 7 months. The roots that did start to grow back had an average of 1.7 new roots arising from them, but each cut root had only one commercial quality root to replace it. These commercial quality roots were growing at an average of 220 cm per host tree per year. The high mortality and slow regrowth following root harvest indicate that many decades will be needed in between intensive titica harvests in one area. Options for managing titica harvests include reducing the percentage of roots removed per plant, setting up blocks of forest that would be harvested in succession, and in some cases integrating titica harvests into long-term timber cutting cycles.

The radial growth of mature cork oak trees ( Quercus suber L.) was studied for 9 years, between two consecutive cork harvests, by measuring monthly diameter stem growth with dendrometers in southwestern Portugal. The average tree annual diameter increment was 0.95 cm per year but significant inter-annual growth differences were observed. Diameter increments were higher in the year following the cork harvest (1.44 cm), and decreased more or less regularly until the end of the cycle (0.41 cm). Smaller annual diameter increments could be related to climatic factors such as drought periods with low winter rainfall. Tree growth was seasonal with radial growth in March–November and dormancy in November–February. On average, the radial growth rate attains a maximum value in June–July and decreases sharply in summer. The growth pattern and seasonality were very similar in all trees and independent of the tree diameter. The results obtained may be used as background information in management systems for cork oak stands, i.e. for optimizing the duration of cork production cycle in relation to the thickness of cork planks, the timing of cork extraction and the development of growth curves.

The shortage of forest products and unsustainability of current land use practices experienced by many hillside farmers in the Caribbean is associated with increasing rates of conversion and degradation of remaining natural forests. This pressure could be alleviated by the establishment of trees in community/farm forests or more integrated agroforestry systems. Indigenous tree species are largely untried for these applications and represent an underexploited resource that may offer a good combination of tolerance of local environmental conditions, together with potential to restore degraded environments. These needs were addressed in the Blue Mountains of Jamaica in a study that combined: eliciting local people’s knowledge about the utility of tree species for a wide range of products and services, assessment of the ecological characteristics of the tree species, and testing the establishment and growth of selected species over three and a half years in on-farm environments. Detailed interviews were conducted with 16 male and 11 female local respondents. Together they reported on the uses of 80 taxa of trees and shrubs, 43 of them indigenous (each respondent naming, on average, 19 taxa). All but one of the trees already present on farmland were exotic, but the majority of respondents were interested in planting more trees. The overall local valuations of each of the species were calculated for 10 uses. Timber and fruit were the highest rated individual uses but, for planting, multipurpose tree species were valued most highly. The respondents were familiar with most, but not all, of the indigenous species that have been recognised as having high commercial timber value. Farm environments on the southern slopes of the Blue Mountains are subject to significant drought as well as frequent disturbance from fire. Fifty-eight tree species indigenous to the montane forests were assessed for their potential suitability for growing in this environment by two indices of their distribution and three of their ecology. Their potential for timber production was also assessed in terms of their maximum size and wood density. Twenty-four of these species (together with one other indigenous timber species and the most highly valued exotic multipurpose tree species) were selected for a species elimination trial with a blocked structure replicated in two sites. After 42 months the species were strongly differentiated in terms of their rates of survival (from 0 to 48%), diameter growth (from 1.7 to 5.1 cm increment over the 42 months for the montane forest species), height growth (84–258 cm increment) and crown and stem form. Performance of most species in the trial could be explained post hoc by selective reference to their distribution and ecological traits in the natural montane forests. However, none of the traits taken alone provided accurate predictions of species’ performance in the trial. The best prediction was provided by a classification of species’ regeneration type with pioneer species tending to do better and shade-tolerant species worse, however there were many exceptions. No relationship was found between species’ performance in the trial and their altitudinal range, abundance in southern slope forest, in secondary forests or on landslides, or their growth rate or maximum stem density in mature forest stands. From the combination of local valuation and trial performance 10 species are recommended for more detailed testing. Of the undomesticated indigenous species, Juniperus lucayana and Clethra occidentalis are particularly recommended, and it is suggested that Turpinia occidentalis, Cinnamomum montanum, Viburnum alpinum, Dendropanax arboreus, Podocarpus urbanii and Prunus occidentalis also be considered because of their good combination of establishment and utility. In addition, from the analysis of ecological characteristics a further 19 species (11 already known to be valued for their utility) are recommended for an additional trial.

We demonstrate how tree stem properties may be linked to the properties of sawn timber through simulation of the structural growth of the tree and of the sawing of the stem into pieces subjected to quality grading. In this context, the growth and development of individual Scots pines ( Pinus sylvestris L.) is presented in terms of the three-dimensional structure of the tree crown as determined by the influence of local light conditions on branch growth, with implications for the distribution of the properties of the stem and wood such as stem form and knots. The three-dimensional distribution of these properties allows one to saw the stem into logs and further into sawn pieces which can be graded based on quality. The part of the stem to be cut into logs is defined by the height of the stump (felling height) and the diameter of a stem fulfilling the minimum top diameter for a log acceptable for sawing. The stems are characterised by means of the number of logs obtainable for sawing, the length of the logs, the top and butt diameters of the logs, their volume and their taper. The wood is characterised for sawing mainly in terms of the occurrence of knots and their size and quality (sound, dead). The sawing algorithm checks the knots in terms of diameter and quality and calculates the grade and value of each piece. This procedure is repeated log by log, and a summary of the sawing is made covering the whole stand, with a report on the total yield and value of the sawn timber obtained from each stand. The performance of the sawing simulator was demonstrated with the example computations on sawing for Scots pine trees. As a result, the quality of sawn timber was found higher in an unthinned stand than in the thinned stands. On the other hand, the sawing yield from individual 100-year-old tree from the thinned stand was larger than from a tree of the same age in an unthinned stand, because of its larger size.

In spite of the importance of cork and cork oak stands in the Portuguese forest and economic scenarios, little research work has been done with this species over the years. The main objective of this study is to define a system of prediction equations to assess air-dried cork weight using dendrometric variables of the tree as predictors. These equations can be used at an intermediate age of the cork production cycle, which is usually of 9 years, or at the year of the stripping process, with 9 years old cork. Several alternative models were developed, from simpler models, using variables easy to gather in the field, to more complex ones that maximise the prediction ability. The development of the weight prediction equations was based on data gathered on three stands located in a region located in the centre/south Portugal, the Coruche county, with average aptitude regarding cork production.

Increasing demands for non-timber forest products and their commercial extractions can result in harvesting methods that maximize short term economic gains with little attention to long term ecological consequences. We assessed the ecological impacts of harvesting techniques used by an indigenous group, the Soligas, on the non-timber forest products they extract from the forests of Biligiri Rangan Hills, south India. Specifically, we examined patterns of resource availability of two non-timber tree species, Phyllanthus emblica and P. indofischeri, and how the current fruit harvesting techniques influence fruit yields, and susceptibility of trees to infestations by hemiparasitic plants of the Loranthaceae family. We also assessed how hemiparasite infestations affect fruit production and growth rates of Phyllanthus trees. There was considerable variation in fruit production in both species of Phyllanthus from one fruiting season to the next. The Soligas harvest an average of 86% (±17.72%) of the fruit yield on a per tree basis in P. emblica and 94.17% (±6.9%) in the case of P. indofischeri. At the population level, 64.75 and 86.6% of the fruit productivity is harvested in P. emblica and P. indofischeri, respectively. However, not all individuals or populations are harvested. Harvesting techniques used resulted in cutting of 15% of P. indofischeri trees and 5% of P. emblica trees. The current harvesting techniques used by the Soligas reduce fruit production in P. emblica in the following year (R2=0.27,p=0.03). Furthermore, the Soligas selectively harvest fruits from trees that have larger fruit crop sizes in both species. Individual trees that carried a greater load of hemiparasites produced significantly lower fruit yields (P. emblica: r=−0.32,p Current harvesting techniques used by the Soligas have negative impacts on trees of Phyllanthus spp., as do infestations by hemiparasites. Current fruit harvesting strategies and techniques used by the Soligas focus on maximizing the economic returns by adopting methods of extraction such as lopping of branches and cutting of trees. Such practices can ultimately decrease the rates at which the populations grow, thereby making the extraction of Phyllanthus fruits unsustainable. Adopting more sustainable methods of harvesting appears to be one viable solution to the current ecological problem facing the conservation of Phyllanthus trees in the forests of Biligiri Rangan Hills.

Palm leaves are an important source of roof thatch for rural communities in many parts of the tropics. Often leaves are harvested from wild populations, and as a non-timber forest product may promote local commitment to forest conservation. Nevertheless, reports suggest that at least some wild populations are declining due to over-harvesting. In Amazonian Ecuador the understory palm Geonoma macrostachys Mart. is often the preferred species for thatching. Here we explore the limits to sustainable harvesting of this species combining ethnobotanical data on the use of this species by the Huaorani indigenous group with ecological data and transition matrix modeling. We find that due to severe light limitation there seems to be little scope for sustainable harvesting of this species from old-growth forest. Instead high rates of sustainable harvesting could probably be achieved in semi-open anthropogenic habitats, e.g. agroforestry systems or young secondary forests. We also find that harvesting scheme has a strong impact on sustainable harvesting rates; if only adults (leaf length 100–223 cm) are harvested, while subadults (leaf length 35–99 cm) are left unharvested, two to three times as much leaf material can be harvested per area (at a fixed density) as when subadults are also harvested.

In Finland, yields of forest berries are a way of measuring the forest’s value as a recreation environment. Berry picking is also an activity of direct economic value. When planning forest management, the effect of silvicultural treatment on berry yields should also be assessed. With the assistance of current forest planning methods, the best method for this assessment is to apply numerical models. This study utilised expert modelling in order to determine the dependence of cowberry and bilberry yields on the characteristics of the site and the tree stand. The modelling technique applied uses the results of paired comparisons of stands, with respect to berry yields, as the dependent variable, and measurable site and stand characteristics as independent variables. Compared to the Analytic Hierarchy Process, the method does not require a complete set of paired comparisons of stands, which means that many stands can be evaluated without unreasonable efforts. The predictions correlated logically with site and stand characteristics and were in line with earlier models.

Widespread commercial harvesting of wild edible mushrooms from the forests of the Pacific Northwest United States (PNW-US) began 10–15 years ago. A large proportion of suitable forest habitat in this region is managed by the Forest Service (US Department of Agriculture) and Bureau of Land Management (US Department of the Interior). These lands are managed under an ecosystem management philosophy that entails multiple-use, sustainable forest product harvesting, resource monitoring, public participation in forest management issues, and holistic planning. Managing the harvest of edible mushrooms engages every aspect of this management philosophy. We examine a variety of issues raised by mushroom harvesting and how these issues interact with forest ecosystem management choices. We discuss regulations currently being used by managers to conserve the mushroom resource while further information is gathered, unique challenges and considerations inherent to sampling fungi, and current research and monitoring activities in the Pacific Northwest. Although current scientific evidence suggests that harvesting likely will not harm the resource in the short term, no statistically-based monitoring information exists about the cumulative impacts of intensive and widespread commercial harvesting over long-time periods. We outline a three pronged approach to long-term monitoring of the resource: (1) tracking harvest quantities in areas with intense commercial harvests; (2) sampling productivity in areas with no mushroom or timber harvests; and (3) conducting research to model the relations between forest management and mushroom productivity. Public participation and a broad collaboration among public land management agencies, private forest landowners, forest managers, researchers, and research organizations will make this approach cost effective and the results widely applicable.

We examine the financial aspects of three silvicultural systems to encourage the sustainability of valuable hardwood species in mixed-dipterocarp forests of southwest Sri Lanka. We compare the net present value (NPV) of the current forest management approach (diameter limit harvests) with shelterwood harvests that promote light hardwood timber species. In this analysis, we also consider the potential of enrichment planting various precious timber (Diospyros quaesita — calamander), and non-timber forest product (NTFP) species (Caryota urens — fishtail palm; Elettaria cardamomum var. major — cardamom; Calamus zeylanicus — rattan) in conjunction with timber harvests. Two real (inflation adjusted) discount rates were used, 4 and 6%, respectively. Results show that when real discount rates are low (4%), and advance regeneration is present, NPV is highest for the one-cut shelterwood (US $9983 ha−1). At a high discount rate (6%), reflecting the current short-term concession system and unstable rights to harvest, and where no advance regeneration was present, the diameter limit system (US $7173 ha−1) was the optimum. On sites with advanced regeneration, the one-cut shelterwood system is clearly preferable. For all but rattan, shelterwood treatments provide higher NPVs for NTFPs than diameter limit cuttings primarily because of the higher light regimes and more growing space made available early in the rotation. The value for tea cultivation (US $26,000 ha−1) far exceeds the value of managing these lands for timber alone, explaining the dramatic expansion in tea plantations on private lands. However, our results suggest that managing these lands for a combination of timber and enrichment plantings of NTFPs (US $23,000 ha−1) can be comparable to tea plantations. By managing for NTFPs and timber, forest managers have new opportunities to solve the old problems of high-grading and land-use conversion.

Cork, a unique biological material, is a highly valued non-timber forest product. Portugal is the leading producer of cork with 52% of the world production. Tree cork weight models have been developed for Southern Portugal, but there are no representative published models for Northern Portugal. Because cork trees may have a different form between Northern and Southern Portugal, equations developed with southern data do not always predict well in the North. An analysis of eight tree variables revealed the interaction between tree circumference (outside bark at 1.3 m) (CSC) and debarking height ( H DEB ) to be the best predictor variable. A nonlinear exponential function was chosen over a simple linear function due to a slight curvature exhibited in the plot of weight over CSC× H DEB . The paper concludes with a section on construction and use of confidence intervals about the mean and individual predictions from the nonlinear regression, plus a method to place bounds on an aggregate estimate for a stand.

Flood plains comprise over 12% of the lowland Peruvian Amazon, and they are economically important in agriculture, fishing, hunting, forestry and extraction of other forest products. Some special features of the flood plains are outlined and their implications for land-use are interpreted. A close interaction exists between terrestrial and aquatic ecosystems, implying that management needs to consider effects on both systems. By nature the flood plains are adapted to large perturbations, indicating that rough management interventions can be carried out, but only a limited proportion of each habitat is disturbed by nature at a time, suggesting that simultaneous profound large-scale interventions in certain habitats should be avoided. The high fertility of flood plain soils and periodical sedimentation hint that the risk of soil nutrient depletion is limited. The flood plain production potential is relatively high, although it varies much according to patterns of flooding and drainage, stressing the need to provide information on the geographic variation in these environmental factors. The culture and organisation of flood plain inhabitants is dynamic, and a patron system dominate in many economic activities. Few regulations control the access to and use of the flood plain natural resources, and no permanent tenure rights can be issued for flood plain land. This emphasises the need to promote adapted organisations and institutions, and to develop a land tenure system fostering incentives for management working on a long-term perspective. It was found that sustained timber production in the natural flood plain forests can have net present values (NPVs) up to US$ 250 per ha without accounting for growth enhancing effects. On the average the extraction value of non-timber forest products (NTFPs) was low, but certain habitats generated high economic benefits constituting a major part of the economy of many flood plain households. Domestication has a high potential and agroforestry is already widespread, but effects of flooding, bad drainage and risk of erosion by the river current are impediments to successful intensive land-use systems. Socio-economic distortions can be risked if land suited for agricultural subsistence production is gradually taken over by agriculturalists focusing on large-scale commercial production.

The traditional harvest of non-timber forest products (NTFP) in Peten, Guatemala, provides a model for integrated conservation and development programs. Conservation International and El Cruce a Dos Aguadas (El Cruce). and agricultural community in the Maya Biosphere Reserve in Northern Peten, have created a new NTFP, called Gatherings™ which is a potpourri composed of seeds, flowers and leaves. Gatherings™ is promoted on international and domestic markets as a sustainably extracted natural product whose sale provides a direct incentive for local producers to conserve their forests. The purpose of this investigation is to test the ecological sustainability of extraction of the natural dyes used to color the potpourri ingredients and to present the following eight-step method for testing the sustainability of NTFP harvesting: (1) delineate current supply area; (2) determine current supply; (3) estimate the growth and yield of target species; (4) determine the current demand; (5) compare short-term supply and demand and evaluate management options: (6) assess secondary ecological effects of harvesting; (7) repeat the process for future time periods; and (8) summarize the analysis. Using this method, we found that two of the dyes are likely to be over-harvested within 10 years, and that the harvest of the third could be increased substantially without endangering the dye-producing species. When we summarized the analysis, we found no evidence to conclude that the current production of Gatherings™ directly benefits the forests of El Cruce. However, the goodwill created by this project has contributed to a new conservation initiative; a Land Management Area which has been proposed by the community to Guatemala's National Protected Areas Council (CONAP) and which contains a 13 273 ha forest reserve.

Lac, a natural resin produced by the lac insect Kerria lacca, is an important income-generating non-timber forest product in India. It is expected that the potential for lac production could increase with India's recent changes in forest policy which encourage the natural regeneration of degraded lands. A review is presented on improved management systems of lac production on Butea monosperma which is the most important lac host tree in India and is prevalent in degraded areas of the sub-Himalayan plains.

This paper reviews environmental accounting and the new household economics (NHE) as important new developments for forest economics, and particularly for assessing non-market and non-timber forest products. The concept of adjusting the national accounts for forest depletion has received a lot of attention, but forest-based household services, like outdoor recreation in developed countries or fuelwood in developing countries, may have greater impacts on the national accounts. NHE is an econometric approach for valuing forest-related household services like these. In general, the NHE allows complete estimates based on revealed preferences for the production, supply and demand of goods and services that some households produce and consume internally. Complete estimates are critical in economies where household services dominate market production and consumption, and where market observations alone would be partial and would misguide policy decisions. Therefore, household services are the important area of application for both environmental accounting and NHE. Applications of each hold special promise for our understanding of the forestry activities of subsistence households in developing countries.

Wild edible mushrooms are important as dietary products in the rural communities of Mexico, and provide additional income during the rainy season. The present study was carried out during the summers of 1990 and 1991 in two Christmas tree stand plots near the town of Topilejo, in Distrito Federal, Mexico, to determine the natural production of wild edible mushrooms. The relationships between production, dasometric and soil characteristics were established; the best emergence came under open canopy.

Malawi's 3.6% rate of annual deforestation is among the worst in the world. Wood fuel consumption and agricultural land conversion are the primary causes. This paper examines the historic evidence and develops a conceptual model of deforestation and the response to it, especially by small-holders and the Forestry Department. The model features indigenous stock and growth, as well as reforestation with new seedlings largely delivered by the Forestry Department. The empirical evidence is sparse and of uncertain reliability. Nevertheless, a cautious specification of the model suggests that smallholders are most responsive. They rapidly reforest in response to economic scarcity, especially where their tenure is secure. Continuing smallholder reforestation activity may be highly dependent on Forestry Department capacity to deliver seedlings and extension services. Continuing deforestation in Malawi will be strictly a function of agricultural land conversion. It will not be due to fuel wood or other wood product demands.

The objectives of this paper were to define, measure and explain differences in the comparative advantage of countries which trade forest products. The theory of Heckscher, Ohlin and Vanek was used, which led to a direct relationship between a country's net trade, its endownment in resources, and its domestic income. From these equations an index of revealed comparative advantage was derived and used to rank countries in the early 1980s for major groups of forest products. This ranking led to country groupings which suggested a definite relationship between the comparative advantage of a country, its endowment in forest and other resources, and domestic demand. This relationship was tested formally with an empirical model based on the Heckscher-Ohlin-Vanek equations. This simple model explained a large part of the variation in the net trade of total forest product, roundwood, sawnwood, panels, pulp, and paper, in the early 1960s and 1980s. In general, there was a strong positive relationship between net trade and the level of domestic demand, reflected by income. For some commodities, especially logs, this relationship had become stronger between the early 1960s and 1980s.