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This study investigated the impact of small rodents on young trees during three growing seasons (2018–2020) in the Czech Republic. Tree damage by small rodents, the quantity and quality of herbaceous plant biomass and the species composition of small mammals were monitored at two sites in European beech forest plantations. The number of trees damaged during three growing seasons correlated positively with fibre content and negatively with nitrogen content in herbaceous plant biomass. The importance of winter precipitation is reflected in the positive correlation with nitrogen content in herbaceous plant biomass. The observed tree-gnawing damage correlated positively with the abundance of one rodent species only—the bank vole. The highest damage occurred after the concurrence of a dry winter and a higher number of voles. Given current climate variability, this situation could become more common in the future. Gnawing may be a limiting factor for the successful restoration of trees with thin bark—in our case, European beech. In addition, the proportion of this woody species should be increased to achieve a more stable and closer composition in the Czech Republic.

Production forestry is known to reduce the naturally variable microhabitat pools in live trees and their biodiversity by tree removal and broad indirect effects of silviculture. However, the tree-scale processes are not known well enough for microhabitat management for the future. This study investigates how tree age affects the microhabitat occurrence in live trees, its effect modifiers, and explanatory value compared with tree diameter. We inventoried tree-related microhabitats on 879 live aspens (Populus tremula) and Norway spruces (Picea abies) of known age in 141 forests representing contrasting productive site conditions in Estonia. We analysed microhabitat incidence using logistic mixed models for significant tree-scale and stand-scale factors. Most microhabitat types appeared rare even in old trees, and the age effects had various patterns. Only 2% of trees bore five or more microhabitat types. Aspens and spruces had a similar microhabitat diversity before 80 years of age. Stand-level effects varied among microhabitat types but were less significant than tree-level effects; interactions were even rarer. Most effects found could be interpreted through known ecological processes; for example, humidity-dependent epiphytic growth; bark stripping by herbivores; pathogen effects in forests with distinct histories. In contrast, a reliable tree-scale prediction of microhabitat occurrence appears rarely possible; and depending on microhabitat type, either tree age or diameter can be a better predictor. We suggest that managing for tree-related microhabitats in production forests should combine facilitating ecological conditions for microhabitat formation, and early detection and retention of the trees with high microhabitat potential.

Forests have been decreasing in number and volume constantly since the oldest detectable date. Although human behaviors constitute the main responsible factor for this decrease, pests, such as insects, fungi, etc. also cause significant destruction in this respect. Approximately 50 harmful insect species are effective in our country's forests every year, and the control against these pests is carried out in about 500 thousand hectares of land. It is vital that authorities become aware of the threats occurring in forest areas, such as fires, insect outbreaks, etc., as soon as possible and initiate the control with the support of the public. There is a need to increase the level of knowledge and awareness of all segments of the society in this regard. On the other hand, tools, such as facilities established in forest areas, traps, and bird nests in forest areas to control pests, should also be protected, or at least not damaged by people living in the environment or by those somehow visiting these areas. In recent years, it has been observed that insects, which cause more damage to forests more than fires, have caused significant economic losses in forest enterprises. These harmful bark beetles cause great destruction and loss of wealth in spruce forests in Artvin region, which is one of the most damaged places in this respect. In this study, the province of Artvin where insect damage is experienced was selected. The methods of combating forest pests that damage spruce trees of the forestry organization working in the province of Artvin and their management methods have been examined and evaluated. The effects of the changes in the forest organization structure on the combat management and the situation in the legal legislation have been examined. In addition, a survey was conducted with 100 people to learn about the behavior and attitudes of the local people on this issue. Authorities must first act with the people of the area to be successful in protecting forests. People of the area should be informed about the control carried out by the forest administration, and their contribution should be considered. In this way, the level of success will increase in this control. In addition, a more effective forest organization structure is required for a successful control.

Ecologically and economically harmful wood borers and bark beetles, which have the capacity to expand geographically through the international log trade, require mitigations to prevent their spread. Detailed phenological knowledge of these pests across the wood-product supply chain can support systems approaches to phytosanitary risk management. Forest insect activity from 3.5 years of monthly, fortnightly, and daily sampling in recent clearfells from eight Pinus radiata plantation regions throughout New Zealand is presented. Phenology varied regionally with some species absent from specific regions. Insect activity declined with postharvest duration to a hypothesised background activity level that may be determined by landscape dispersal processes. Maximum temperature was the strongest predictor of flight activity with a 15 °C threshold that increased the probability of flight. Probability of a flight event was calculated for each species at monthly, fortnightly, and daily periods. Although wintertime activity was low, operationally effective temporal periods of low pest prevalence could not be defined on a monthly basis. Assurance of temporal periods of low pest prevalence as part of a systems approach will require additional supporting evidence of the relationship between forecast weather on short temporal scales (days), the probability of flight, and the relationship between low-level flight activity and the risk of wood product infestation by dispersing insects.

Seasonality influences the abundance and activity of forest insects. Harvesting during periods of reduced activity could minimise colonisation risk on logs and reduce the need for phytosanitary treatments. We describe the winter colonisation dynamics of Pinus radiata logs in operational harvest sites in New Zealand and assess the probability of log colonisation as a function of captures in flight interception traps. After 15 days, 3% and 1% of logs were colonised by Hylastes ater and Hylurgus ligniperda (Coleoptera: Scolytinae), respectively, and 1% by Xenocnema spinipes (Coleoptera: Curculionidae). The same three species were captured in traps. Our observations showed that logs exposed for ≥ 2 weeks are predicted to have a more than 1% probability of bark beetle colonisation, whereas logs removed from forests within 24 or 48 h had predicted colonisation rates of 0.13% and 0.26%, respectively. A positive relationship between trap capture and log colonisation was also observed. Average catches of 98% log colonisation. A positive relationship was also shown between log colonisation rates and temperature. A 12.3 °C temperature threshold predicted colonisation rates of 5, 50 and 95% with thermal sums of 10, 20 and 30 degree-hours, respectively. Models based on exposure time, trap catches, or environmental factors can estimate seasonal probability of insect colonisation, which aids identification of periods of low pest pressure when treatments could be avoided or reduced.

Long rotation period of trees and complex trading procedures of wood, are major impediments in spread of agroforestry. Thus, alternative for providing early return to farmers along with long term benefits of raising trees on their farmlands are necessary. Generally, ~ 25% of the trees can be used as timber while the other parts viz. bark, leaves, roots, branches etc. have limited use and are often burnt. In process, leakage of C sequestration potential of trees is reduced. But, tree twigs and leaves can be the potential source of bioactive compounds or secondary metabolites especially in arid region. Vegetation in arid regions possesses very special and unique chemicals which help them to adapt to prevailing harsh conditions. Water stress in these vegetation leads to production of high quantity of reactive oxygen species (ROS) which through a series of pathways eventually leads to higher production of certain special secondary compounds. These compounds, in nature improve defense mechanism of trees, but also have immense pharmaceutical, food, cosmeceutical, nutraceutical and agrochemicals value. They are locally used as folklore medicine but their commercial exploitation can provide short term benefits to farmers. Also, unlike bole, which can be exploited only once, these benefits from trees can be exploited many times during their growing period. Therefore, in this article research work on important secondary metabolites produced by major agroforestry systems of arid region of India has been reviewed along with their industrial applications.

Large sugar pine mortality was associated with recent growth and defense measures. Many old-growth pine forests across the western United States have encountered widespread and concerning increases in tree mortality attributed to increased competition and reduced vigor associated with prolonged fire exclusion that can make trees more vulnerable to bark beetles. We investigated the importance of growth and resin duct defense on recent mortality of large sugar pine (Pinus lambertiana) in a fire-excluded, mixed-conifer forest of the Sierra Nevada, in California, USA. Growth and defense were measured from tree rings for 33 pairs of live and dead sugar pine. The 10-year trend in basal area increment prior to sampling declined by 1.78 cm2 year− 1 in sugar pine that died and increased by 0.34 cm2 year− 1 in paired live sugar pine. The 10-year trend in resin duct total area showed declines of 0.0154 mm2 year− 1 in trees that died and increases of 0.0068 mm2 year− 1 in trees that survived. The most informative models of large sugar pine mortality included measures of both growth and defense. The top model included the trends of basal area increment and resin duct total area 10 years before mortality, and growth variability 5 years before mortality. In general, trends and variability in growth and defense over shorter time windows (

Norway spruce (Picea abies (L.) Karst.) is a major production tree species for the European wood industry. However, it is highly sensitive to bark stripping (BS) by red deer (Cervus elaphus L.), which causes large timber losses. Because the red deer population has increased over the last decades, a better understanding of the underlying causes driving BS is urgently needed. BS outbreaks are multifactorial: winter food shortage, local and regional deer abundance and stand properties (thermal and visual cover, and scarcity of herbaceous layers) have been found to drive BS rates. Although the influence of each of these factors is well studied, there is still no consensus on their relative contributions to BS or what mitigation strategy is best. In this study, we made use of a long-term, large-scale BS inventory (13 years over 2570 km2) to fill these gaps. We modeled winter and summer BS rates in response to the most explanatory variables, selected from a large set of environmental variables. Our results highlight the prevalence of deer abundance combined with high sensitivity of coniferous thickets and pronounced habitat selection by deer for these stands. Our findings show that the control of red deer populations is a key measure for reducing BS in Norway spruce stands.

Forests in the western United States are being subject to more frequent and severe drought events as the climate warms. The 2012-2015 California drought is a recent example, whereby drought stress was exacerbated by a landscape-scale outbreak of western pine beetle (Dendroctonus brevicomis) and resulted in widespread mortality of dominant canopy species including ponderosa pine (Pinus ponderosa). In this study, we compared pairs of large surviving and beetle-killed ponderosa pines following the California drought in the southern Sierra Nevadas to evaluate physiological characteristics related to survival. Inter-annual growth rates and tree-ring stable isotopes (∆13C and δ18O) were utilized to compare severity of drought stress and climate sensitivity in ponderosa pines that survived and those that were killed by western pine beetle. Compared to beetle-killed trees, surviving trees had higher growth rates and grew in plots with lower ponderosa pine basal area. However, there were no detectable differences in tree-ring ∆13C, δ18O, or stable isotope sensitivity to drought-related meteorological variables. These results indicate that differences in severity of drought stress had little influence on local, inter-tree differences in growth rate and survival of large ponderosa pines during this drought event. Many previous studies have shown that large trees are more likely to be attacked and killed by bark beetles compared to small trees. Our results further suggest that among large ponderosa pines, those that were more resistant to drought stress and bark beetle attacks were in the upper echelon of growth rates among trees within a stand and across the landscape.

The development of the mining industry has led to the appearance in many parts of the world of vast technogenic territories from which toxic heavy metals enter the environment and food chains. Physical, chemical, and biological methods of cleaning industrial land due to technological complexity and high cost are relatively little used on a large scale. Natural forest overgrowth of mining sites and the removal of heavy metals by woody plants can be an effective form of recovery. Therefore, the study of this process is of significant scientific and practical interest. The analysis of the annual growth in height and width of the annual rings of the stem of Scots pine (Pinus sylvestris L.) in 2004–2019 was made on the territory of the Uchalinsky mining and processing plant (South Ural, Russia) contaminated with heavy metals. Relatively high concentrations of copper and zinc were found in soils, roots, bark, young shoots, comparable to exceeding the maximum allowable concentrations. Despite the spatial uniformity of the heavy metal content in the stands, the tree samples significantly differed in terms of annual growth. Results suggest that the lack of nutrients and not stress from exposure to heavy metals is the main reason for relatively low growth rates on slopes of industrial wastes. It was confirmed by studying the annual growth in height of the undergrowth in habitats with different soil cover conservation. The data prove the relatively high potential of Scots pine for the natural recovery of industrial lands polluted with heavy metals by mining enterprises.

Key message Models for quantifying tree biometric properties, imperative for forest management decision-making, including height, diameter, bark thickness and volume were developed, and wood basic density was documented for dry Afromontane forests of south-central Ethiopia. Abstract Tree biometric properties such as height (ht), diameter at breast height (dbh), bark thickness (bt), volume and wood basic density (wbd) are imperative for forest management decision-making. For dry Afromontane forests in south-central Ethiopia, models for quantifying such tree properties are totally lacking. This study, therefore, aimed at developing models for ht based on dbh, for dbh based on stump height diameter (dsh), for bt based on dbh, for volume based on dbh, ht and crown width (crw), as well as documenting wbd data. Comprehensive and representative datasets were collected from Degaga–Gambo and Wondo Genet forests. The ht, dbh and bt modelling were based on 1345 sampled trees during forest inventories, while the volume modelling and wbd documentation were based on 63 destructively sampled trees from 30 species covering 87% of the total basal area in the study sites. Weighted least squares regression was applied for modelling and leave one out cross-validation was used for evaluation. The ht–dbh and dbh–dsh models performed well (pseudo-R2 = 0.72 and 0.98), while bt–dbh performed poorer (pseudo-R2 = 0.42). Models for the total tree, merchantable stem and branches volume were developed with different options for independent variables, where pseudo-R2 varied from 0.74 to 0.98, with smallest values for the branches models The models may be applied to forests outside the present study sites provided that the growing conditions are carefully evaluated. The species-wise wbd was ranging from 0.426 to 0.979 g cm−3, with the overall mean of 0.588 g cm−3. The wbd data will be useful for building up a national wbd database and may also be included in the Global Wood Density database. The study represents a significant step towards sustainable forest management including REDD + MRV practices in the dry Afromontane forests of south-central Ethiopia.

Veteran trees are keystone structures currently in decline worldwide. In Europe, veteran oaks (Quercus spp.) are important habitat trees for wood-living beetles. Still, we have limited knowledge of the drivers determining the composition of these communities and the relevant spatial and temporal scales for these drivers. We collected beetles from 32 hollow oaks in two regions in Southern Norway along a coast-inland gradient paralleling historical onset of oak harvesting. We focused on species with different host-association to oak and identified the relative importance of processes working on different spatial scales, ranging from tree-scale to region-scale, as well as effects of the coast-inland gradient. We found all the spatial scales to influence the species composition, with a response to the coast-inland gradient and differences between the regions for all beetle groups. The tree scale was the most important scale for species mainly associated with oak, generalist species and the overall species composition—with bryophyte cover on the stem, depth of bark crevices and amount of wood mould as the most important variables. The close surroundings and forest variables on the landscape scale was most important for the beetle species restricted to broadleaf trees. Our study confirmed established knowledge, but also revealed new relationships between oak-associated beetles and relevant drivers on the tree and regional scale. As important responses of species mainly associated with oak or broadleaf trees were concealed when analyzing the total community, care should be taken not to base management recommendations on such overall, general patterns.

Previous studies have shown that vocalizations of dogs can provide information to human companions. While acoustic signals of dogs have been intensively studied during the last decade, barking during hunting activities remains unstudied. The experiences of hunters indicate that owners can recognize what animal species has been found based on the bark of their dog. Such a phenomenon has never been tested before. We tested such an ability by comparing barks that were produced when dogs encountered four different animal species: wild boar, red fox, rabbit and fowl. Classification results of a discrimination analysis showed, that based on barks of dachshunds and terriers, it is possible to categorize towards which animal species barks were produced. The most distinctive barks were produced during encounters with the most dangerous of these animals, the wild boar. On the contrary, barks evoked by red fox encounters were classified similarly as those towards other smaller and non-dangerous animals like rabbits and fowl. Although the red fox represents a potentially dangerous species, the barking provoked was not classified with a much higher result than barking at animals that pose no threat. This might indicate that the key parameter could be the body size of the animal the dog meets. We further tested whether the degree of threat from the species of animal the dog encounters is reflected in the structure of the acoustic parameters based on the valence-arousal model. We found that barks produced in contact with a wild boar showed significantly lower frequency parameters and longest duration compared to other barks. According to these results, it seems that the variability of barking depending on the species of animal a dog encounters is an expression of the dogʼs inner state rather than functionally reference information.

In this work, we discussed the pathways and mechanisms responsible for transmission of nematode from bark beetles to pine trees and vice versa. The deterministic model, treated in this paper, seems quite robust in its qualitative behaviour. In order to check the fidelity of model and its implementation, we took the real data of pines which became infected in Korea from 2010–2019. Our model shows almost accurate estimate of infectious pine trees appeared in Korea. The severity of disease has been checked through the calculation of sensitivity indices of the contact parameter $$R_0$$ with respect to all the parameters. The results obtained by varying the parameters for infectious class of hosts and vectors have also been used to design effective control strategies to reduce the infection. Efficacy of controls has been shown through numerical simulations.

Detarium microcarpum Guill. & Perr. is a priority food tree species in West Africa, but its use pattern and conservation is little known across different sociocultural areas of Benin. In this study, we analyse the determinants of D. microcarpum traditional uses pattern and how these determinants influence the species’ conservation in Benin. Thus, 730 respondents were participated in semi-structure interview across the North and Central regions of Benin. The information related to local names, traditional uses of different plant parts, management systems and conservation of D. microcarpum was recorded from the respondents. Use value (UV), ethnobotanical use value (EUV) and organ use value (OUV) were calculated. These statistics were used to assess the structure and variability of traditional use categories of plant parts among the sociocultural groups, gender and age groups. Results indicated that local names were spatially structured and linked to local communities’ cultural origins, according to the recent human migration roads in West Africa. In total, 42 traditional uses of seven categories were gathered. UV in relation to sociocultural groups ranges from 7.62 (Idatcha and Fon) to 16.08 (Peulh and Lokpa); within the gender, UV ranges from 9.96 (women) to 11.15 (men); and within the age groups, UV ranges from 9.37 [18–30 years old] to 14.14 [65–100]. The species’ UV significantly depended on respondents’ sociocultural group, age and gender. Moreover, the age, gender and sociocultural groups significantly influenced the species’ use pattern. Ethnobotanical use value ranges from 0.35 (fodder) to 6.22 (traditional human medicine). OUV ranges from 2.62% (flower) to 42.38% (leaf). The various uses of the species’ roots, leaves and bark in traditional pharmacology and their high-quality firewood and tasty fruits determined the various local management systems. Thus, considering the current threats (intensive use of the roots, trunk, leaves and branches, and habitat degradation) conservation measures are needed to ensure the survival, conservation of distribution pattern and sustainable use of the species.

Uses, Knowledge, and Management of the Threatened Pepper-Bark Tree (Warburgia salutaris) in Southern Mozambique.Warburgia salutaris, the pepper-bark tree, is one of the most highly valued medicinal plant species in southern Africa. Due to its popularity in folk medicine, it is overexploited in many regions and is deemed threatened throughout its range. We identified cultural and social drivers of use, compared knowledge distribution, determined management practices, and explored local ecological knowledge related to the species in the Lebombo Mountains, Tembe River, and Futi Corridor areas in southern Mozambique. Stratified random, semistructured interviews were conducted (182), complemented by 17 focus group discussions in the three study areas. W. salutaris was used medicinally to treat 12 health concerns, with the bark being the most commonly used part. Knowledge of the species varied between the three areas, but not with respondent gender or age. Harvesting was mostly through vertical bark stripping (71% of informants). To promote sustainable use of the species, we suggest multiple conservation approaches, including the use of alternative species with the same application, substitution of bark by leaves, and increases in alternative sources of plant material through cultivation. Additional information on species demography, harvest impact, and post-harvest bark recovery rate area is required. Information obtained in this work can contribute to management guidelines and plans for the species in Mozambique.

Bark and ambrosia beetles (Scolytinae) are frequently introduced to new areas through international trade of wood and wood products. When novel host trees are encountered, they can be naive and susceptible to attack, enabling previously harmless scolytine species to become damaging, or the symbiotic fungi of ambrosia beetles to become pathogenic. Invasive Scolytinae are often only recognised after they have become harmful, so the early detection of such species is important for forest protection and management. The first nationwide survey of Scolytinae in Great Britain was conducted between 2013 and 2017, to determine the presence and distribution of previously undetected alien species. Study sites included pine, spruce and oak forests and forests near ports where wood and forest products are imported. Insect traps baited with ‘broad-spectrum’ lures were employed to maximise the diversity of scolytine species collected. Three recently established alien species were detected, Xylosandrus germanus, Gnathotrichus materiarius and Cyclorhipidion bodoanum; the latter two species are new records for Britain. All three species appear to be largely restricted to south-east England at present, and strikingly, all are ambrosia beetles. Current EU plant health regulations for wood importation and movement are limited in their effectiveness against ambrosia beetles, since bark removal does not typically destroy them. In the relatively cool summer climate of Britain, southern England appears to provide the most optimal thermal conditions for the establishment of invasive wood and bark-boring beetle species.

Wilt disease has become a threat to Acacia plantations in SE Asia. There are about 1.3 million ha of Acacia auriculiformis, A. mangium and Acacia hybrid plantations in Vietnam that require management of wilt disease caused by Ceratocystis manginecans. To identify options for management, we examined affect of pruning (tree age, pruning time and pruning technique) and site traits (altitude, slope and position) on disease expression from natural infections. Ceratocystis wilt disease and disease indices were more serious in younger than older pruned trees. Pruning in the rainy season resulted in heavier infection by Ceratocystis than pruning in the dry season. Decreasing bark tearing during pruning reduced the levels of infection and disease. Tip pruning of branches reduced disease compared to pruning close to the trunk. The interaction effects of terrain factors showed that A. auriculiformis and Acacia hybrid plantations were most severely affected when trees were planted in foot-hills, at altitudes below 300 m and on slopes below 15o. Results for the pruning time and pruning technique trials have application for reducing the impact of Ceratocystis wilt disease in Acacia plantations in Vietnam.

Timber quality is the main driver of timber prices and is strongly influenced by the competition a tree experiences until its day of harvest. Regulating competition is an integral part of silviculture, and therefore, deeper understanding of the competitor’s influence on timber quality is important. Since mixed forest stands and the share of broadleaved tree species have increased in the recent past because of a changed forest policy in several countries, effects of mixture types on timber quality are of increasing importance. In this study, we investigated the effects of intra- and interspecific competition on the internal timber quality of European beech (Fagus sylvatica L.). To analyze the effects of competition intensity and competitor species identity on the timber quality of 82 target beech trees, three different approaches were used: terrestrial laser scanning (TLS), a quality assessment on the standing tree by local district foresters, and a quality assessment of the sawn wood (boards) after harvesting. We investigated the relationship between external and internal quality features and additionally compared the different approaches to assess quality. We found that the present competitive situation was partly related to internal timber quality, with increasing competition leading to increased internal timber quality. We further observed more discoloration in timber of beech trees growing in mixture with other broadleaved tree species. We also showed that predicting discoloration is possible through the number of bark anomalies on the stem surface. Also, the external quality assessment of local foresters on standing trees predicted the internal timber features well. Finally, TLS appeared to be a valuable addition for assessing timber quality in situ.

The recent Californian hot drought (2012–2016) precipitated unprecedented ponderosa pine (Pinus ponderosa) mortality, largely attributable to the western pine beetle (Dendroctonus brevicomis; WPB). Broad-scale climate conditions can directly shape tree mortality patterns, but mortality rates respond non-linearly to climate when local-scale forest characteristics influence the behavior of tree-killing bark beetles (e.g., WPB). To test for these cross-scale interactions, we conduct aerial drone surveys at 32 sites along a gradient of climatic water deficit (CWD) spanning 350 km of latitude and 1000 m of elevation in WPB-impacted Sierra Nevada forests. We map, measure, and classify over 450,000 trees within 9 km2, validating measurements with coincident field plots. We find greater size, proportion, and density of ponderosa pine (the WPB host) increase host mortality rates, as does greater CWD. Critically, we find a CWD/host size interaction such that larger trees amplify host mortality rates in hot/dry sites. Management strategies for climate change adaptation should consider how bark beetle disturbances can depend on cross-scale interactions, which challenge our ability to predict and understand patterns of tree mortality., The 2012–2016 drought and western pine beetle outbreaks caused unprecedented mortality of ponderosa pine in the Sierra Nevada, California. Here, the authors analyse drone-based data from almost half a million trees and find an interaction between host size and climatic water deficit, with higher mortality for large trees in dry, warm conditions but not in cooler or wetter conditions.

Background Predictive models of post-fire tree and stem mortality are vital for management planning and understanding fire effects. Post-fire tree and stem mortality have been traditionally modeled as a simple empirical function of tree defenses (e.g., bark thickness) and fire injury (e.g., crown scorch). We used the Fire and Tree Mortality database (FTM)—which includes observations of tree mortality in obligate seeders and stem mortality in basal resprouting species from across the USA—to evaluate the accuracy of post-fire mortality models used in the First Order Fire Effects Model (FOFEM) software system. The basic model in FOFEM, the Ryan and Amman (R-A) model, uses bark thickness and percentage of crown volume scorched to predict post-fire mortality and can be applied to any species for which bark thickness can be calculated (184 species-level coefficients are included in the program). FOFEM (v6.7) also includes 38 species-specific tree mortality models (26 for gymnosperms, 12 for angiosperms), with unique predictors and coefficients. We assessed accuracy of the R-A model for 44 tree species and accuracy of 24 species-specific models for 13 species, using data from 93 438 tree-level observations and 351 fires that occurred from 1981 to 2016. Results For each model, we calculated performance statistics and provided an assessment of the representativeness of the evaluation data. We identified probability thresholds for which the model performed best, and the best thresholds with either ≥80% sensitivity or specificity. Of the 68 models evaluated, 43 had Area Under the Receiver Operating Characteristic Curve (AUC) values ≥0.80, indicating excellent performance, and 14 had AUCs Conclusions Approximately 75% of models tested had acceptable, excellent, or outstanding predictive ability. The models that performed poorly were primarily models predicting stem mortality of angiosperms or tree mortality of thin-barked conifers. This suggests that different approaches—such as different model forms, better estimates of bark thickness, and additional predictors—may be warranted for these taxa. Future data collection and research should target the geographical and taxonomic data gaps and poorly performing models identified in this study. Our evaluation of post-fire tree mortality models is the most comprehensive effort to date and allows users to have a clear understanding of the expected accuracy in predicting tree death from fire for 44 species.

Fires and insect outbreaks are important agents of forest landscape change, but the classification and distribution of these combined processes remain unstudied aspects of forest disturbance regimes. We sought to map areas of land characterized by homogenous fire regime (HFR) attributes and by distinctive combinations of fire, bark beetles and defoliating insect outbreaks, and how their distribution might change should current climatic trends continue. We used a 41-year history of mapped fires and forest insect outbreaks to classify HFRs and combined fire and insect disturbance regimes (HDRs). Spatially constrained cluster analysis of 2524 20-km grid cells used mean annual area burned, ignition Julian date, fire size and fire frequency to delineate HFR zones. Mean annual areas burned, affected by bark beetles, and affected by defoliators were used to delineate HDR zones. Random forests classification used climate associations of HDRs to project likely changes in their distribution. Eighteen HFR zones accounted for 30% of variance, compared to 27 HDR zones accounting for 59% of variance. Fire regime designation had low predictive power in explaining 23 homogenous insect outbreak regimes or the 27 HDRs. Climate change projections indicate a northward migration of current HDR zones. Conditions suitable for defoliator outbreaks are projected to increase, resulting in a projected increase in the total rate of forest disturbance. When describing forest disturbance regimes, it is important to consider the combined and possibly interacting agents of tree mortality, which can result in emergent properties not predictable from any single agent.

New measures for effective monitoring and controlling of bark beetle infestations are needed as a response to intensified outbreaks caused by the climate change. Various environmental factors affect tree health and susceptibility, as well as stand predisposition to bark beetles. European spruce bark beetle Ips typographus L. abundance and outbreak frequency in Finland has significantly increased during the last decade. The ability to identify sites under a high risk of infestation would facilitate adaptation to this new situation and help target limited forest health management resources. Accordingly, our goal was to investigate the importance of various stand, soil and topographic characteristics in the assessing predisposition of Norway spruce dominated urban forest in southern Finland to I. typographus infestations. Information on the environmental factors was assessed in the field in 2014 and derived from a digital elevation model. Ips typographus infestation intensity was classified into three infestation index classes based on tree-wise symptoms of resin flow, discoloration and defoliation. Cumulative logit link models were utilized for investigating stand-level infestation probability. The best explanatory factors were aspect, slope, site type and soil texture. Models with the highest cumulative probabilities for severe infestation were linked with eastern aspect, moderate steep slope and rich site type fertility (0.72) and eastern aspect, shallow soil and rich site type fertility (0.71). Higher soil C/N ratios with east aspect and rich site type fertility was associated with an increased risk of severe infestation in a third model. The lowest risk was associated with southern and southwestern aspects, fine soil texture, moderate site fertility and gentle slopes.

Owing to the continual attacks by pests particularly the bark-beetles (viz borers), there has been tremendous destruction of the forest resources. Beetle attacks are also responsible for severe production loss in commercial crops, thus leading to distress to farmers. In this paper, we have presented a novel approach to detect the pest attack in yielding cashew trees at early stage, i.e. to develop a portable unit. The preliminary analysis of bark samples (taken at height of 1.5 meter) shows a clear distinction between the good and infested trees. Also, the chlorophyll analysis performed on leaf samples shows the result for good and different stages of infestation as decrease in absorbance values of the leaf extract. The proposed design will indicate the status of a cashew tree by analysing the chlorophyll content of leaves and conductivity of bark, both of which will be utilised to make an ultimate confirmation.

Culturally modified red pine (Pinus resinosa) can be added to the long list of natural and artificial features that comprise the cultural landscape of the Boundary Waters Canoe Area Wilderness of Minnesota, U.S.A. This study provides historical context for the first cultural-modification dates derived from the dendrochronological evaluation of primary-growth, fire-killed red pine in the Border Lakes region. The tree-ring-based data are interpreted in the context of archaeological records, fur-trade era travel accounts, and ethnographic information to shed new light on the economy of the Border Lakes Ojibwe from the late 1700s to the early 1900s. Multiple lines of evidence from Lake Saganaga suggest that these culturally modified red pine were intentionally wounded in order to extract pitch, which was used to make the gum critical for constructing and repairing birch-bark canoes. Culturally modified red pine are a tangible artifact class that may serve to reframe modern perspectives on the critical role of the birch-bark canoe for transport in the historical Border Lakes landscape. These trees are living symbols of historical land-use patterns and are indicative of the strategic geography of the fur trade.

The social pseudoscorpion Paratemnoides nidificator is a common species in the Brazilian tropical savannah (Cerrado), where colonies are found under the bark of trees. In this environment, colonies hunt for large insects, subduing them by cooperative effort. Small insects are offered as food to nymphs, but large prey tends to be shared by colony members. We investigated the cooperative capture of large prey (Scarabaeidae beetles) by colonies of P. nidificator. During this process, some adults are involved in the immobilization and killing of prey. However, other adults stay as profiteers and do not offer help to subdue the prey. After prey immobilization, pseudoscorpions perform a hierarchical food share in which the attackers begin sucking the prey. These individuals favor the nymphs, offering them the prey and protection during feeding. Profiteer individuals are the last to feed on the carcass. In P. nidificator, obligatory parental care probably favors the evolution of behavioral strategies that prioritize the feeding of juveniles. This mechanism can provide better-quality food for the attackers but offers food to all colony members.

Tomicus minor Hartig (Col., Curculionidae, Scolytinae), occurring on Pinus sylvestris L., is a species which demonstrates high reproductive capability on weakened stands, accelerating the process of forest death. In protected areas, T. minor is regarded as a sensitive bioindicator that reacts to decline in the health and vitality of forests. Although there have been many publications concerning T. minor, no precise method has yet been given for estimating its population so as to enable the monitoring of forest vitality and assessment of the role played by T. minor in the forest ecosystem. The aim of the present work is to develop a statistical method for estimating populations of T. minor, requiring minimum work and interference with the forest ecosystem and permitting the computation of estimation errors. Research was carried out in the years 1992–2011 in pine stands aged over 80 years, growing in a variety of habitats and situated at varying distances from sawmill timber yards. Attack density of T. minor was measured on trap logs made from uninfested living trees. The population of T. minor on the trap logs was described using a multiple linear regression model with two explanatory variables. Among the features investigated, the T. minor population was found to depend significantly on the number of egg galleries on the fifth metre of the trap log counted from the thinner end (p 0.5), confirming the high accuracy of the developed model.

The two storms Vivian (1990) and Lothar (1999) left an area of roughly 9000 ha of fully damaged protection forests in Swiss mountain regions. Given this huge dimension, questions arose on how to manage these areas to keep the protection gap, i.e. the time period with reduced overall protection against natural hazards, short. Quantifications are presented for the stability of lying logs left in place, the frequency of post-disturbance mass movements, and the tree regeneration in windthrow areas. The average height above ground of unsalvaged lying logs decreased from 2.1 m shortly after disturbance to 0.8 m 20 years later. In the period 1990–2014, the number of avalanches in windthrow areas was markedly small, and annual rates of shallow landslides and debris flows in windthrow areas did not differ from rates in comparable undamaged forested areas. Regeneration density rarely exceeded 4000 stems ha−1 20 years post-windthrow at elevations above 1200–1500 m a.s.l. Mean height of tallest trees reached 5.6 m in areas that were cleared and 6.5 m in those left unsalvaged. Trees planted post-windthrow were 1.0–2.4 m taller than naturally regenerated ones. Practitioners rated the protective effect to be acceptable 24 years post-disturbance in only 5 out from 16 observed windthrow areas (31%), with planting trees as the main cause of success. We conclude that in protection forests the regeneration speed after disturbance rarely meets practitioner’s expectations in terms of both stem density and stand structure. However, leaving woody debris from wind disturbance in place proved to replace protective effects for an astonishingly long time. An intensive management with salvage logging, planting and even technical constructions seems therefore only inevitable on windthrown areas where risks seem too high based on hazard, damage potential and possible spread of bark beetles to nearby protection forests. A management alternative applicable to many other cases of windthrown protection forests is to plant trees between lying stems.

Key message The dog detection allows timely removal by sanitation logging of first beetle-attacked trees before offspring emergence, preventing local beetle increases. Detection dogs rapidly learned responding to synthetic bark beetle pheromone components, with known chemical titres, allowing search training during winter in laboratory and field. Dogs trained on synthetics detected naturally attacked trees in summer at a distance of > 100 m. Context An early detection of first beetle-attacked trees would allow timely sanitation felling before offspring emergence, curbing local beetle increase. Aims We tested if detection dogs, trained off-season on synthetic pheromone components from Ips typographus, could locate naturally bark beetle–infested spruce trees. Methods Indoor training allowed dogs to discriminate between the infestation odours (target) and natural odours (non-target) from the forest. Odour stimuli were shown by chemical analysis to be bioactive at extremely low-levels released (−4 ng/15 min) in the laboratory. Results Detection dogs, trained to recognise four different synthetic pheromone compounds in the wintertime, were able to detect naturally infested spruce trees unknown to humans the following summer. The dog-handler pairs were able to detect an infested spruce tree from the first hours of beetle attack until several weeks after first attack, long before discolouration of the crown. Trained sniffer dogs detected infested spruce trees out to ≥ 100 m, as measured by GPS-collar tracks. Conclusion Dog-handler pairs appear to be more efficient than humans alone in timely detecting bark beetle infestations due to the canine’s ability to cover a greater area and detect by olfaction infestations from a far longer distance than can humans.

Bark beetle outbreaks in the Rocky Mountains caused substantial tree mortality starting in the late 1990s, and continued into the 2000s, with the most severe mortality occurring from 2002 to 2012. Over the same time period, concentrations of dissolved copper in the Big Thompson River (BTR), Colorado, USA, increased significantly and are high enough to negatively affect aquatic life. We examined correlations between dissolved copper and tree mortality in the BTR. Two sites, one consisting of water from the western side of the continental divide and one consisting of water from the eastern side, demonstrated a positive relationship between percentage tree mortality and dissolved copper. The relationships were similar except that the best relationship occurred with a 3-year lag between tree mortality and subsequent dissolved copper levels at the eastern site and with a 5-year lag at the western site. The differential time lag is potentially the result of different levels of carbon in the soil in the watersheds associated with each site because carbon can affect copper mobility. Our results suggest that bark beetle-induced tree mortality may contribute significantly to dissolved copper levels in the BTR.

Fuel reduction treatments have been widely implemented across the western US in recent decades for both fire protection and restoration. Although research has demonstrated that combined thinning and burning effectively reduces crown fire potential in the few years immediately following treatment, little research has identified effectiveness of thinning and burning treatments beyond a decade. Furthermore, it is unclear how post-treatment disturbances such as a bark beetle outbreak affect fuel treatment effectiveness. We evaluated differences in surface and canopy fuel characteristics and potential fire behavior metrics between fuel reduction treatments (no-action or control, burn-only, thin-only, thin+burn) implemented in ponderosa pine (Pinus ponderosa Lawson & C. Lawson)−Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco)-dominated forests that were subsequently affected by a mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak after treatment. Experimental units were measured in 2002 (immediately following fuel treatment) and in 2016 (14 years after treatment and at least 4 years following a beetle outbreak). We found that beetle-altered thinning treatments (thin-only and thin+burn combined) had less fuel (i.e., 34% and 83% lower fine and coarse woody debris loading, respectively) and lower crown fire potential (i.e., 47% lower probability of torching and 42% greater crowning index) than corresponding unthinned treatments (control and burn-only). There was no post-beetle-outbreak effect of burning treatments (burn-only and thin+burn combined) on surface fuel loading, but burning reduced crown fire potential (i.e., 37% greater crowning index) over unburned units (control and thin-only) 14 years after treatment. Additionally, we determined the relative impacts of fuel treatments and the bark beetle outbreak on fuel and crown fire potential differences and found that bark beetle-caused tree mortality inflated differences between controls and thinned treatments (thin-only and thin+burn) for surface fuel loading and probability of torching, but diminished differences between these treatments for canopy fuel loading, canopy bulk density, and crowning index. Despite the differential effects of bark beetle-caused tree mortality in the treatments, our study suggests that the effects of fuel treatments on mitigating crown fire potential persist even after a stand-transforming insect outbreak, especially when thinning and burning are combined.

Snags are used as habitat by several organisms, including bark- and wood-boring beetles, which contribute to snag decomposition and facilitate subsequent snag colonization by other organisms. However, snags seldom occur in young managed forests. This study examines how snag characteristics and spatial arrangement affect bark- and wood-boring beetle colonization and survival in spruce plantations subjected to commercial thinning, thinning with biomass removal and thinning with snag creation where a few clumps of trees were girdled. To this end, we documented the volume of snags, their characteristics and the number of beetle emergence holes in their basal section. Beetle colonization and survival to adulthood in snags was ~33 times greater when expressed per unit area in plantations supplemented with clumps of girdled trees than in other thinning regimes where low densities of beetle emergence holes per hectare were documented. Snag diameter at breast height, snag species and thinning treatments influenced the number of emergence holes per snag. Positive spatial autocorrelation between the abundance of emergence holes per snag was detected but no other spatial effect was noticeable. This work suggests that vertical deadwood is a limiting factor for bark- and wood-boring beetle colonization within plantations and challenges current thinking about the effect of thinning on beetle communities that was developed from window trap studies. These results underline the importance of large diameter snags for beetle conservation within managed forests and demonstrate that tree girdling during thinning entries is a viable method for creating snags to enhance beetle colonization and survival.

A pet that goes missing is among many people's worst fears: a moment of distraction is enough for a dog or a cat wandering off from home. Some measures help matching lost animals to their owners; but automated visual recognition is one that - although convenient, highly available, and low-cost - is surprisingly overlooked. In this paper, we inaugurate that promising avenue by pursuing face recognition for dogs. We contrast four ready-to-use human facial recognizers (EigenFaces, FisherFaces, LBPH, and a Sparse method) to two original solutions based upon convolutional neural networks: BARK (inspired in architecture-optimized networks employed for human facial recognition) and WOOF (based upon off-the-shelf OverFeat features). Human facial recognizers perform poorly for dogs (up to 60.5% accuracy), showing that dog facial recognition is not a trivial extension of human facial recognition. The convolutional network solutions work much better, with BARK attaining up to 81.1% accuracy, and WOOF, 89.4%. The tests were conducted in two datasets: Flickr-dog, with 42 dogs of two breeds (pugs and huskies); and Snoopybook, with 18 mongrel dogs., Comment: 17 pages, 8 figures, 1 table, Multimedia Tools and Applications

Context Growing evidence suggests that climate change could substantially alter forest disturbances. Interactions between individual disturbance agents are a major component of disturbance regimes, yet how interactions contribute to their climate sensitivity remains largely unknown. Objectives Here, our aim was to assess the climate sensitivity of disturbance interactions, focusing on wind and bark beetle disturbances. Methods We developed a process-based model of bark beetle disturbance, integrated into the dynamic forest landscape model iLand (already including a detailed model of wind disturbance). We evaluated the integrated model against observations from three wind events and a subsequent bark beetle outbreak, affecting 530.2 ha (3.8 %) of a mountain forest landscape in Austria between 2007 and 2014. Subsequently, we conducted a factorial experiment determining the effect of changes in climate variables on the area disturbed by wind and bark beetles separately and in combination. Results iLand was well able to reproduce observations with regard to area, temporal sequence, and spatial pattern of disturbance. The observed disturbance dynamics was strongly driven by interactions, with 64.3 % of the area disturbed attributed to interaction effects. A +4 °C warming increased the disturbed area by +264.7 % and the area-weighted mean patch size by +1794.3 %. Interactions were found to have a ten times higher sensitivity to temperature changes than main effects, considerably amplifying the climate sensitivity of the disturbance regime. Conclusions Disturbance interactions are a key component of the forest disturbance regime. Neglecting interaction effects can lead to a substantial underestimation of the climate change sensitivity of disturbance regimes. Electronic supplementary material The online version of this article (doi:10.1007/s10980-016-0396-4) contains supplementary material, which is available to authorized users.

This study was conducted to evaluate the performance of six stem taper models on four tropical tree species, namely Celtis luzonica (Magabuyo), Diplodiscus paniculatus (Balobo), Parashorea malaanonan (Bagtikan), and Swietenia macrophylla(Mahogany)in Mount Makiling Forest Reserve (MMFR), Philippines using fit statistics and lack-of-fit statistics. Four statistical criteria were used in this study, including the standard error of estimate (SEE), coefficient of determination (R2), mean bias (), and absolute mean difference (AMD). For the lack-of-fit statistics,SEE, and AMD were determined in different relative height classes. The results indicated that the Kozak02 stem taper model offered the best fit for the four tropical species in most statistics. The Kozak02 model also consistently provided the best performance in the lack-of-fit statistics with the best SEE, and AMD in most of the relative height classes. These stem taper equations could help forest managers and researchers better estimate the diameter of the outside bark with any given height, merchantable stem volumes and total stem volumes of standing trees belonging to the four species of the tropical forest in MMFR.

Mary-Anne Lea travels to remote coastal regions to study marine animals for insights into conserving their species. Mary-Anne Lea travels to remote coastal regions to study marine animals for insights into conserving their species.

International audience; AbstractKey messageWe provided a precise quantitative analysis of the factors at the origin of bark damage during harvesting operations and developed a model able to predict them accurately. The major factors were the distance of trees to skid trails, the intensity of removals, the harvesting system as well as the interactions between the distance of trees to skid trails with harvesting systems, the average skidding distance, the tree species and tree height.• ContextDuring timber harvesting, trees in the remaining stand may suffer bark damage resulting from tree-felling or log manipulation. Although a multitude of case studies and empirical observations provide qualitative and quantitative information with respect to the potential causal factors, the basic quantitative relationship between major factors of influence and the resulting degree of bark damage remains largely unclear.• AimsThe objective was to provide a precise quantitative analysis of impact factors explaining the occurrence of bark damage during harvesting operations.• MethodsThree different modelling approaches were tested: boosted regression tree (BRT), a generalised linear mixed effects model (GLMM) and Bayesian Markov chain Monte Carlo generalised linear mixed models (MCMCglmm).• ResultsThe major factors with a significant impact on the occurrence of bark damage were the distance of trees to skid trails, the intensity of removals, the harvesting system and the interaction term between the distance of trees to skid trails with harvesting systems, average skidding distance, tree species and tree height.• ConclusionThe final model includes the relevant major factors impacting on the infliction of bark damage during practical harvesting operations. Furthermore, it discriminates well with respect to the occurrence of bark damage, and it provides managers with a rational and conclusive tool for optimising harvesting operations.

This study aims to develop a series of robust and efficient methodologies, which can be applied to understand and estimate firebrand generation and to evaluate firebrand showers close to a fire front. A field scale high intensity prescribed fire was conducted in the New Jersey Pine Barrens in March 2013. Vegetation was characterised with field and remotely sensed data, fire spread and intensity was characterised and meteorological conditions were monitored before and during the burn. Firebrands were collected from different locations in the forest and analysed for mass and size distribution. The majority were found to be bark slices (more than 70%) with substantial amounts of pine and shrub twigs. Shrub layer consumption was evaluated to supplement the firebrand generation study. Bark consumption was studied by measuring the circumference variation at several heights on each of three different pine trees. The variation was in the same order of magnitude as the bark thickness (1–5 mm). Testing and improving the protocol can facilitate the collection of compatible data in a wide range of ecosystems and fire environments, aiding in the development of solutions to prevent structural ignition at the Wildland Urban Interface.

Silvopastoral systems have been increasingly adopted in Brazil, often supported by public policies, such as the federal government’s “Low Carbon Agriculture” program. These systems integrate diversification, income generation and environmental protection. However, predation of mature trees by cattle can be a problem, causing large economic losses. As the causes of this predation are not precisely known, few alternatives are available to prevent or reduce damages. The present study aimed to evaluate the vulnerability of Eucalyptus grandis, E. saligna, E. pellita, E. dunni, E. urophylla, E. urograndis (clones I144, I224, C219 and H13) and the clone COP 1277, an E. grandis × E. camaldulensis hybrid, to predation by cattle. Damages caused by chewing leaves and bark and breaking branches and trunks were evaluated in a silvopastoral system comprised of Brachiaria decumbens, cattle and Eucalyptus spp. The cattle showed a marked selection of E. grandis and E. urograndis I144 clone. The eucalyptus types least prone to damage were E. pellita and E. urograndis H13 clone.

Process-orientated, unmanaged forest remnants are not sufficient for halting the loss of forest biodiversity. Thus, integrated biodiversity-promoting management for forest inhabitants is needed. Microhabitats, such as tree cavities or bark pockets, are essential for the preservation of saproxylic species and of critical importance for endangered ones. This study investigates (1) which factors trigger the formation of microhabitats at both the individual tree and aggregated plot level, and (2) whether the co-occurrence of microhabitats differs between managed (=logged) and unmanaged forests. Relationships between the occurrence of 17 microhabitat types and individual tree features (e.g. light availability, and tree vitality) and plot characteristics (e.g. stand density index and stand age) in 398 plots dominated by Fagus sylvatica or Pseudotsuga menziesii in Germany and the USA were studied using random-effects logistic and normal regression modelling. Separate analyses were performed for German beech forests, German Douglas-fir forests, and the US Douglas-fir forests. Our results show that (1) tree diameter in breast height (DBH), tree vitality and branchiness or epicormic branches are highly related with the occurrence of one or more microhabitats on individual trees in managed and unmanaged beech and US Douglas-fir forests. In managed German Douglas-fir forests, vitality is not a predictor for the occurrence of microhabitats on a tree, but tree density and the maximum age of trees in a stand in addition to DBH and branchiness have an effect. Time since last management is not a statistically significant predictor for the presence of microhabitats at the tree level, but it is for German beech at the plot level. In Douglas-fir-dominated forests both in Germany and in the USA, the stand density index was the only common predictor at the plot level. (2) Unmanaged German beech and Douglas-fir forests exhibit more statistically significant and positive correlations with microhabitat groups than managed stands, implying that the presence of one microhabitat group on a tree is associated with the presence of other microhabitat groups. We finally conclude that measures for supporting microhabitat inhabitants in managed forests are scale and species dependent (tree versus plot level; beech versus Douglas-fir-dominated forests). Trees that carry microhabitats seem to have similar features independently of forest management. At the plot level, density management may trigger the accumulation of microhabitats. Our results indicate that in forest management, it is possible to consider the factors influencing the formation of microhabitats and implement adequate forest practices to advance their formation.

There are increasing demands on silvicultural practices to reduce the adverse impacts of harvesting. Damage to residual trees caused by ground-based skidding was assessed in stands with low [3.4 stems per hectare (sph), 14.36 m3/ha], medium (5.2 sph, 21.61 m3/ha), and high (7.1 sph, 25.95 m3/ha) harvest intensities. Skidding was conducted using a cable skidder. After the skidding operation, a field survey was conducted to collect data on all residual trees (species, dbh, height) and on tree wounds (size class, location, intensity of damage). It was hypothesized that increased harvest intensity leads to increased injury rates. The treatment with the highest harvest intensity was found to cause the highest percentage of damage and the largest stem wounds. The most common types of damage were stem wounds to the cambium layer and bark scrapes. In all three harvest intensity treatments the probability of individual tree damage decreased as skid-trail cross slope decreased and distance to skid-trail edge increased. It is concluded that harvesting intensity should be limited to 5 trees/ha during each harvesting operation to reduce extent of tree damage and thus future financial loss.

Native Sami people have lived for thousands of years in northern Fennoscandia, subsisting on reindeer herding, hunting, fishing and gathering of wild plants. Harvesting inner bark from Scots pine (Pinus Sylvestris L.) was a common practice and traces of this resource use are still evident in old forests. In this study we analyzed trees with bark-peelings in a nature reserve in northernmost Sweden to assess the magnitude and spatiotemporal patterns of inner-bark harvesting. We found that the same inner-bark harvest locale was used repeatedly, in nearly every decade from the late 16th to the late 19th century and that harvest levels varied greatly over time. The harvest levels we observed were surprisingly low, in comparison to levels suggested in other studies, and indicate that inner-bark was used as a supplementary health food during early spring when game meat was naturally lean, rather than being used as bulk food year-round.

Economic Importance of the Medicinal Plant Trade in Sierra Leone. This study identified, quantified, and evaluated the economic importance of the medicinal plant trade in Sierra Leone so that recommendations for conservation could be made. We carried out a quantitative market survey. We interviewed 120 vendors in three major cities and all vendors in two towns near a national park. Apart from the semistructured interviews, specimen samples were collected and identified, prices noted, and sales units measured. More than 40 species were traded in urban markets, nine species being the most frequently traded in all three cities. Only two plants were traded in the towns: Xylopia aethiopica (Dunal) A.Rich.and Garcinia kola Heckel. Most plants were traded in the form of dried bark or leaves. It was estimated that at least USD 64,000 are being annually traded in informal markets in major cities, the nine species most frequently traded contributing most of the retail value. Little information was found on import/export figures. Results from this study indicate that the trade of certain medicinal plants could be promoted as an alternative livelihood strategy for edge communities of protected areas. However, more information is needed on harvesting techniques, source and abundance of the species traded.

Detailed knowledge on habitat requirements is a key to successful conservation actions. The marbled jewel beetle Poecilonota variolosa (Buprestidae) has a wide global distribution but populations are often scarce and typically fragmented. In Sweden it is monophagous on aspen Populus tremula and is classified as near threatened on the Swedish Red List due to its rapid population decline. This study aimed to investigate habitat preferences and regional-scale distribution patterns of P. variolosa in southern Sweden in order to suggest conservation measures. Aspen trees in four study areas in the province of Smaland were surveyed for exit holes during late summer 2011. The occurrence and number of exit holes (both new and old ones) per tree were compared between study areas and habitat types, and were related to the sun exposure and bark thickness of individual trees. Further, the occurrence of new and older exit holes was related to tree sun exposure and bark thickness. The most preferred habitat types were aspens on clear-cuts, followed by roadside aspens, aspens in pastures, and aspens in closed forest. Thick bark and high sun exposure were consistently significant as predictors for both occurrence and number of new exit holes per tree. The majority of exit holes were located towards south. Our results indicate several useful management measures: to retain aspen on clear-cuts, to cut alongside roads and around some selected coarse aspens in closed forests and in pastures.

The commercial feasibility of sawmilling depends on the expected volume and value of sawn planks. Models that predict the volume of sawn timber of a particular quality and produced from logs of known characteristics are therefore very useful. The objectives were to study variation in sawing yield and to obtain models that predict lumber volume and grade recovery on the basis of easy-to-measure predictor variables of saw logs. Forty-six oak trees growing in Galicia (NW Spain) were felled and cut into logs. The logs were visually graded and sawn mainly into quartersawn planks, which were dried, planed and visually graded for structural purposes. The total volumetric sawing yield was 47.6 %. The sawing yield for planks of structural dimensions (cross-section, 70 × 120 or 70 × 170 mm) was 43.4 %, but decreased to 8.4 % for structural sized and quality grade beams because of wane and biotic damage in many pieces. Log grade did not significantly affect sawing yield in the sample analysed, despite the wide range of diameter over bark at the smallest end in the sampled logs (22–77 cm). The sawing pattern affected total sawing yield (F = 4.913; p value = 0.001) and the sawing yield for structural planks (F = 6.142; p value = 0.0002); radial sawing with one cut and live sawing of half logs provided the highest yields. Three models were proposed for estimating sawn volume in timber products, with the small-end log diameter over bark as the predictor variable and R adj 2 between 0.31 and 0.78 (p value

The sea contains large amounts of resources that are sometimes considered as waste. Such material includes the waste generated by the fish-processing industry and seaweed that is washed up on shores. In this study, these waste products were windrow composted, along with pine bark as a source of carbon and aeration. The final mix proportions were 20 % seaweed, 20 % fish waste, and 60 % pine bark (v/v). After 10 weeks, stable, well-structured, hygienic compost, which was rich in organic matter and nutrients and had a low metal content, was obtained. Tests for maturity, hygiene, and phytotoxicity, along with a detailed physical and chemical characterization, showed that this compost can be used as an organic amendment and/or growth substrate for use in ecological agriculture. The only limiting feature was the high salinity, which could easily be lowered prior to composting the material.

We construct dry weight equations for hybrid aspen growing on former farmland in Sweden. Dry weight equations for fractions of hybrid aspen trees were also made. We estimated biomass production in 24 stands. The stands were located in Sweden at latitudes ranging from 55 to 60° N. The mean age was 18 years (range 15–23), the mean stand density 1090 stems·ha−1 (range 378–2374), and the mean diameter at breast height (over bark) 178 mm (range 85–244 mm). Soil types in the hybrid aspen stands were mainly clay (21 stands), tills (2 stands) and other (1 stand). The mean total standing dry weight above stump level (≈ 200 mm) for the hybrid aspen stands was 135±53 t·ha−1 with a range of 42–219 t·ha−1. In addition to estimating conventional dry weights of trees and tree components, basic density, specific leaf area (SLA), projected leaf area (PLA) and leaf area index (LAI) were estimated and were in agreement with published figures.

Salvage logging—the removal of dead trees in disturbed forest stands—has been controversially discussed. We investigated the impact of bark beetle attacks and subsequent salvage logging on insectivorous bats in a temperate mountain forest. We quantified bat activity (25,373 min counts; 32 plots) using batcorders during 221 all-night surveys in stands killed by bark beetles, with dead trees removed or not, and in vital, single- or multi-layered mature forest stands. We analysed the differences in activity of all bats in general and of bats of foraging guilds (open habitat, forest edge, closed habitat) in these habitats using a generalized linear Poisson mixed model, with plot and observation as random factors, and temperature and habitat as fixed factors. Only open-habitat foragers were slightly more active in salvage-logged stands than in bark-beetle-affected stands; they generally benefited from an open forest canopy, whereas closed-habitat foragers did not. Our results indicated that: (1) bats are less affected by salvage logging after a disturbance of a magnitude typical for European forests, probably because enough roosts are present in surrounding areas, (2) habitats for open foragers are improved by bark beetle infestation and (3) bats are poor bioindicators of negative impacts of salvage logging after natural disturbance in forests with a composition typical for Central Europe.

Kose, Nesibe/0000-0001-5766-0526; Yurtseven, Huseyin/0000-0003-2469-9365 WOS: 000301788100001 Rockfalls can cause serious damage to people, property, facilities and transportation corridors. Furthermore, rockfalls are major hazards in mountain areas with negative impacts on individual trees and forested ecosystems. We conducted a study of rockfall events on 117 mapped (91% of total trees in the stand with > 1.3 m in height and > 5 cm diameter at breast height) Turkish fir trees (Abies bornmuelleriana Mattf.) in a stand within the KayaarkasA +/--Top double dagger ular Village, Inebolu district, Kastamonu province of Turkey. The study site of 0.35 Ha is located on the transition zone of frequently passing rockfall fragments (similar to 40 cm in diameter) generally causing healable injuries. Parameters of trees and injuries were recorded and analysed as to injury number, height and size. Bivariate correlation analysis were used to investigate the relationships between: a) diameter at breast height and number of injuries per tree, b) diameter at breast height and total injury size, c) the number of injuries and total injury size and d) the number of injuries per tree and distance from the source of the rockfall area. Results indicate that the average height of injury, average number of injuries and average injury area to be 81.3 cm (STDEV: 49.8), 7.46 (STDEV: 4.4) and 628.6 cm(2) (STDEV: 678.2), respectively. In total 84% of all injuries were recorded within 160A degrees sector at the upslope side of trees and callus tissue that had closed wounds was observed in 79.1% of all injuries. Furthermore 14.5% of injured trees had callus tissue in the process of closing wounds while 6.4% of injuries had not formed any callus tissue. The most common injury types were bark and wood injuries. Bivariate correlation analysis indicated strong relationships between diameter at breast height and the number of injuries (r(s) = 0.524), injury number and total injury area (r(s) = 0.653) and distance from rockfall area and injury numbers relations (r(s) = -0.518). A weaker relationship was found between diameter at breast height and total injury area (r(s) = 0.363). These results indicate that bigger trees are more prone to rockfall injuries. As expected, trees further from the rockfall area seem to be less prone to rockfall injuries. From our results, it can be inferred that the protection of people and property can be increased through the maintanance of forest in areas immediately below areas prone to rockfall. This stand is still managed in selective forest management system. In order to protect the settlement at the deposition zone it has to manage for protective goals with uneven-aged and multilayered stand structure.

The present study broadly focused on medicinal plant species collected from wild by the villagers for different purposes in the upper catchment of Dhauli Ganga in Nanda Devi Biosphere Reserve (NDBR), in the central Himalaya. A schedule based survey was conducted during the years 2003–2005 in 15 villages of Chamoli district part of the NDBR. Information was collected from collectors, vaidya (medicine man) and those dealing with domestication and marketing of the medicinal plants. The aim of the study was to understand the prioritiesed medicinal plants, their mode of collection and document their ethnobotanical uses by the Bhotiya tribal communities, in this world heritage site. During the survey, 50 medicinal plants belonging to 31 families and 44 genera were documented. Out of these, 70% were harvested from the wild, 22% were cultivated and 8% were cultivated as well as wild harvested. Of the cultivated species, 8% were found growing in the kitchen gardens and 14% in the agricultural fields. However, 42% of the plants had their roots and rhizomes used followed by leaves (26%), seeds (10%), seed and leaf (8%), bark and whole plant (6%) and flower (1%). Most plants were reported to be used for rheumatism (16), followed by stomach disorder (14), cold and cough (11), and jaundice (9). Thirty three plants species were reported to have more than one therapeutic uses, while 17 species were reported to be used against single ailment. The distance of villages from road head was one of the factors contributing to the decline in the medicinal plant population in their natural habitats. The availability of medicinal plants increased with increase in distance from road head and also the peoples’ dependence on them. Documentation of the traditional knowledge will help in conservation of knowledge and also opportunity for using it for future training and use. The result of this study will help in promoting sustainable cultivation and implementation in conservation protocol of those species, which are in the verge of extinction in this region.