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El objetivo de este trabajo es proveer información sobre las principales aportaciones que ha hecho el Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP) en materia de plagas y enfermedades forestales, durante sus primeros 35 años de existencia. El estudio se basa en una revisión bibliográfica que comprende el periodo desde la fundación del Instituto Nacional de Investigaciones Forestales, antecesor del INIFAP, hasta el presente. Destaca la aportación de ambos institutos sobre el conocimiento taxonómico, biológico y de control de insectos descortezadores de coníferas (Dendroctonus spp. e Ips spp.), moscas sierra de las coníferas (Zadiprion spp., Neodiprion spp. y Monoctenus spp.), así como de otros defoliadores del orden Lepidoptera y algunas plagas exóticas. En cuanto a enfermedades forestales, son notables los estudios de diagnóstico de los agentes causales de pudriciones y royas, principalmente hongos (Fusarium spp., Rhizoctonia spp., Cronartium spp, Colletotrichum spp.) y el diagnóstico, impacto y control de plantas parásitas, tanto en bosques naturales como en arbolado urbano y plantaciones. En los últimos años, sobresale la contribución del INIFAP con conocimientos que fundamentan la Norma Oficial Mexicana NOM-019-SEMARNAT 2017, alusiva a la prevención y control de insectos descortezadores; y el estado del arte sobre las moscas sierra de las coníferas. Este esfuerzo se ha dirigido, fundalmente, al diagnóstico y control de plagas y enfermedades forestales; sin embargo, los investigadores del INIFAP enfrentan el reto de generar información y tecnología que permita prevenir y mitigar los efectos del cambio climático en la salud de los bosques.

Driftwood in river catchments might pose a hazard for the safety of infrastructures, such as dams and river dwellers, and thus is often removed. Genissiat dam in France presents a case study where annually approximately 1300 tons of driftwood are removed to prevent driftwood sinking and to protect the dam infrastructure. Collected river driftwood is rarely studied for utilization purposes and is commonly combusted or landfilled. However, driftwood can be valorized for biochar production through pyrolysis or hydrothermal carbonization (HTC). This study follows a novel approach in characterizing river driftwood by identifying the different common genera present at Genissiat dam on the upper Rhone, France. Moreover, the research provides for the first time a comprehensive analysis of river driftwood different physico-chemical properties, such as moisture content, major elemental composition (CHNSO), HHV, and macromolecular composition (cellulose, hemicellulose, lignin, and extractives). The study shows that the transportation of driftwood through rivers can enhance its properties by reducing the bark content resulting in lower ash content. Results indicate that driftwood can be mixed and further processed as a feedstock regardless of their genera and type for biochar production by pyrolysis or hydrothermal carbonization.

The United Nation’s Decade on Ecosystem Restoration 2021–2030 aims to halt ecosystem degradation to achieve Sustainable Development Goals (SDGs) by 2030. In Malaysia, the concept of sustainable forest management (SFM) has been practiced since 1901. In this study, we evaluated the genetic diversity of the native dipterocarp timber tree Shorea acuminata in a rehabilitated area at Kenaboi Forest Reserve (Kenaboi FR). The rehabilitated area was formerly a degraded forest managed with the taungya restoration system for 50 years. All trees with diameter at breast height (DBH) of 5 cm and over were measured, tagged and identified in a one-hectare study plot. A total of 132 inner bark samples were collected for DNA extraction. Four SSR markers (Sle280, Sle392, Sle475 and Sle566) and two EST-SSR markers (SleE07 and SleE16) were used to analyse 95 good-quality DNA samples. Genetic diversity parameters including maternal contribution were determined for 75 samples. The genetic diversity of big trees (He = 0.656 ± 0.19) and small trees (He = 0.652 ± 0.17) were high and both were in genetic equilibrium, with Fis values of the big trees being 0.035 and small trees being 0.164. Clustering analysis based on Jaccard’s similarity values (at 95% confidence level) confirmed that big trees in the Kenaboi FR rehabilitated area had originated from genetically diverse seed trees of the Sungai Menyala Forest Reserve which were used as the planting stock for the taungya restoration system. Maternal contribution showed that the allele contribution of the small trees came from the planted S. acuminata trees within the study area. The high genetic diversity of small trees in this study provides strong evidence that the existing big trees would be suitable for a genetically diverse seed collection to rehabilitate other degraded forests. Sustainable forest management must emphasise genetic diversity in order to ensure the resilience of rehabilitated forest ecosystems.

The springtail, Tetrodontophora bielanensis, dwells in the litter and upper soil layers. This arthropod mainly inhabits humid litter and soil and prefers a cold climate. We determined the main factors influencing this springtail in forests at the landscape level in Krkonoše and site level in Orlické hory in the Czech Republic. We used passive trunk-tree traps. These traps are highly effective for sampling flightless fauna. We used 128 traps in Krkonoše and 17 traps in Orlické hory. The springtail was significantly positively influenced by the presence of Norway spruce (Picea abies) at the landscape level. Springtails’ abundance was, furthermore, influenced by the spatial distribution of the sampling sites. The negative influence of bark coverage and the presence of fungi, and positive influence of an increasing dimension of trees were significant at the site level. We argue for a more diversified management of mountainous forests with respect to forest history. This appears to be also important for mountainous forests in protected areas.

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.

Bark beetles vector symbiotic fungi and the success of these mutualisms may be limited by competition from other microbes. The outcome of fungal competition is strongly influenced by the physical and chemical conditions of the wood they inhabit. These conditions are in turn subject to climatic variation. In particular, wood moisture content (MC) influences fungal competition and, therefore, could help determine environmental suitability for thousand cankers disease (TCD) caused by Geosmithia morbida and its vector Pityophthorus juglandis. We conducted competition experiments in Juglans nigra wood that was naturally or artificially colonized by G. morbida and other fungi over a range of wood MC expected across prevailing United States climatic conditions. G. morbida outcompeted antagonistic fungi Clonostachys and Trichoderma spp. at Aspergillus spp. outcompeted G. morbida at low moisture in wood from Indiana. We fit a logistic regression model to results of the competition experiments to predict survival of G. morbida across the United States. Expected survival of G. morbida was highest in historical TCD epicenters and accounted for the low incidence and severity of TCD in the eastern United States. Our results also predict that under future climate scenarios, the area impacted by TCD will expand into the native range of J. nigra. Given its role in emergent forest health threats, climate change should be a key consideration in the assessment of risks to hardwood resources.

Tree damage is one of the destructive behaviors of the Asiatic black bear (Ursus thibetanus G. (Baron) Cuvier, 1823), and this type of damage causes great economic loss to the forest. A survey about Himalayan white pine (Pinus wallichiana (A. B) Jacks, 1836) damages was conducted at Kaghan Valley, District Mansehra, Khyber Pakhtunkhwa, Pakistan. Field surveys were carried out within five major sites of Kaghan Valley, including Manshi reserve forest, Kamal Bann reserve forest, Malkandi reserve forest, Noori Bichla reserve forest, and some Guzara forests. Line transects and diameter at breast height (DBH) methods were selected for data collection. Eighteen transects were placed in different sites of the valley. A total of (n = 201) affected trees were observed from eighteen transects, along with a total population of 1081 trees with the encounter rate (ER: 0.657) and the mean DBH is x¯ = 71.97 cm. Among total damages, the most severe (n = 39: 19.4%) were fully damaged with a greater encounter rate. Bark stripping was made during the late winter season and used as foodstuff when natural food is limited in the area. In severe cases, the bear-stripped bark encircles from the entire tree trunk, which results in the drying of trees and, finally, falls. Among all five sites, Manshi reserve forest was greatly affected, where the highest number (n = 76) of tree damage, and (n = 21) the entire diameter of trunks were damaged. People of the study area claimed that the black bear causes great forest damage, as well as crop destruction that leads to high economic loss.

En México, uno de los principales agentes de degradación forestal son los insectos descortezadores; entre ellos, Dendroctonus mexicanus es considerado uno de los más agresivos, ya que cada año afecta a varias especies de pino en México. El presente estudio tuvo como objetivo analizar la distribución temporal y espacial de esta especie, a partir de las bases de datos de las notificaciones forestales oficiales, entregadas a la Secretaría de Recursos Naturales (Semarnat) de 2009 a 2018. Las bases de datos se revisaron, analizaron y depuraron. Se correlacionó la variable área ecológica (norte, centro y sur) en la superficie afectada mediante un modelo de efectos fijos. Durante el intervalo de años en estudio, el escarabajo de la corteza se distribuyó en 25 estados de la república mexicana, principalmente en la Sierra Madre Occidental, Sierra Madre Oriental y Eje Neovolcánico Transversal. Los años con mayor número de registros fueron de 2012 a 2014, con presencia en bosques de pino-encino y encino-pino. Nuevo León, Chihuahua, Durango, Zacatecas y Michoacán tuvieron la mayor superficie afectada por D. mexicanus. Michoacán, Oaxaca, Durango, Estado de México, Nuevo León y Chihuahua fueron las entidades que presentaron una mayor cantidad de madera afectada por la plaga. El valor de la prueba global de F2,14 (efectos fijos) fue de 17.99, y el valor p fue de 0.0001. Entre las tres zonas analizadas existen diferencias altamente significativas en cuanto a la variable de respuesta.

Significance Amazonia is experiencing an increase in the frequency of extreme droughts and wildfires. However, the duration of their impacts on plant mortality and carbon stocks are poorly known, and it is unclear whether impacts are amplified in forests with a history of previous human disturbance. We show that plant mortality rates remain above baseline levels for over 3 y in forests affected by drought and 2.5 y in forests affected by both drought and fire. A history of human disturbance led to greater plant mortality in forests simultaneously affected by drought and fire. Our assessment of an area covering 1.2% of the Brazilian Amazon shows that regional drought and fires can have globally relevant impacts on the world’s carbon balance., With humanity facing an unprecedented climate crisis, the conservation of tropical forests has never been so important – their vast terrestrial carbon stocks can be turned into emissions by climatic and human disturbances. However, the duration of these effects is poorly understood, and it is unclear whether impacts are amplified in forests with a history of previous human disturbance. Here, we focus on the Amazonian epicenter of the 2015–16 El Niño, a region that encompasses 1.2% of the Brazilian Amazon. We quantify, at high temporal resolution, the impacts of an extreme El Niño (EN) drought and extensive forest fires on plant mortality and carbon loss in undisturbed and human-modified forests. Mortality remained higher than pre-El Niño levels for 36 mo in EN-drought–affected forests and for 30 mo in EN-fire–affected forests. In EN-fire–affected forests, human disturbance significantly increased plant mortality. Our investigation of the ecological and physiological predictors of tree mortality showed that trees with lower wood density, bark thickness and leaf nitrogen content, as well as those that experienced greater fire intensity, were more vulnerable. Across the region, the 2015–16 El Niño led to the death of an estimated 2.5 ± 0.3 billion stems, resulting in emissions of 495 ± 94 Tg CO2. Three years after the El Niño, plant growth and recruitment had offset only 37% of emissions. Our results show that limiting forest disturbance will not only help maintain carbon stocks, but will also maximize the resistance of Amazonian forests if fires do occur.*

Extensive areas of old forests have declined all over the temperate regions of Europe mainly due to extensive forestry. This is likely to have negative impact on bats that roost in trees, such as the western barbastelle Barbastella barbastellus. We investigated its selection of summer roosts in a commercially used landscape in southern Sweden. We captured and radio-tracked 14 bats and found 17 occupied roosts. Nine of the roosts, including two used by a maternity colony (ca. 30 females), were located between overlapping boards on the gables of barns. The remaining eight roosts, all used by single individuals, were under lose bark on thin trees (DBH = 0.2–0.35 m). All recorded roosts had entrances pointing downwards, were adjacent to deciduous trees providing protective darkness, and were in areas without artificial lighting. In the barns, the bats avoided the northern aspect, which is the lightest (sun sets in the NW and rises in the NE). Roost temperatures did not differ between tree- and barn roosts. Average ambient light intensity on emergence and return was 13.3 lux (SD = 10.1 lux). Roosts in trees and barns shared common physical characteristics, yet despite this both maternity roosts were located in barns, perhaps because such roosts had more space than available tree roosts. Our results suggest that in areas deprived of large trees and extensive old forest, barbastelle shows flexibility in roost selection, although they consistently avoid artificial lights of all kinds. An abundance of potential roosts in trees and buildings and absence of light pollution are therefore key elements in a holistic conservation program for this species.

The aim of the present work was to estimate the productivity and costs of timber harvesting and forwarding during the first commercial thinning of a Scots pine stand. Three harvesting models were introduced and compared: narrow trail, wide access trail, and schematic extraction. The analyzed harvesting equipment consisted of a track mini-excavator (34 kW) with a stroke harvester head (gripping range 4–30 cm), and a farm tractor coupled to a logging trailer with a hydraulic crane. Merchantable timber (roundwood with a minimum diameter of 5 cm inside bark) was harvested from a 25-year-old planted Scots pine stand growing on a grid of 1.4 m × 1.8 m. The study showed the productivity of the mini-harvester ranged from 3.09 to 3.47 m3/PMH15 (productive machine hours plus 15 min), and that of the forwarding equipment to be 4.07 m3/PMH15. The analyzed model of productivity as a function of tree volume and thinning intensity was statistically significant, but the intensity parameter was significant only on plots located along wide access trails (3.7 m) and insignificant on plots located along narrow access trails (2.5 m). The distance between trees was not found to be significant. The calculated net machine costs for the forwarding equipment and track mini-harvester were EUR 36.12 and 52.47 per PMH, respectively. An increase in the usage rate of the harvesting equipment to 80% would reduce the harvesting and forwarding costs to EUR 22.07/m3.

Apart from frugivory, we have limited knowledge of the ecological consequences of primate herbivory. We aimed to ascertain the effects of spring folivory and winter bark/bud herbivory by Japanese macaques (Macaca fuscata) on tree species and succession patterns of cool-temperate forests with heavy snow. To evaluate the impact of herbivory on individual trees, we assessed the growth and mortality of trees consumed by simulating herbivory on nine tree species over 4 years. Additionally, we assessed the cumulative impacts of bark/bud herbivory observed at the tree community level by monitoring the patterns of natural herbivory for almost a decade and evaluating the structure of tree assemblages in places with different cumulative impacts of herbivory. The results of simulated herbivory showed that the mortality caused by both spring and winter herbivory was limited (

The population densities of I. typographus and P. chalcographus inside the Carpathian Mountains increasing mostly because of the non-synchronized and divers management strategies. The growing loss of trees from one year to another indicates assessment to determine the influence of the current management practices (or the absence of such) on bark beetle densities. A comprehensive tree-year assessment were made inside the Apuseni Natural Park, with a surface of 75,784 ha, to assess the population density of bark beetles. High abundance of both species were detected from one year to another, both in managed and unmanaged forests, the latter explained by the presence of scattered wind falling trees which represent favorable places for oviposition. General linear modelling revealed that the effect of environmental variables (forest mean age, forest density, altitude and slope) on I. typographus density were only significant under management systems, and only forest age has significantly negative effect on bark beetles densities. Overall, we conclude that there is little difference in population between non-intervention and intervention areas and even over a relatively short period of time (2011–2013), the population of both species expanded, and new uninfected habitats were infected both in unmanaged and managed forests, therefore a synchronized management system has to be developed. Climate variables as temperature and precipitations has more significant effects on population density than management.

The 14C method is an approach used to determine the proportion of carbon derived from biomass and fossil fuel in the co-fired flue gas. Its accuracy is mainly limited by the deviations between the applied biomass fuels’ 14C activity reference value and virtual value. To enrich the theoretical basis of the 14C method when applied to a Chinese biomass and coal co-firing power station, this study performed field sampling experiments and established a new evaluation method based on domestic literature. Unlike previous studies, this study revealed that the 14C activity of biomass far away from fossil carbon sources was 0.7–1.3 pMC lower than the local atmosphere. The 14C activity laws between tree rings and barks, specifically between eucalyptus bark and poplar bark were different, due to different growth models and different bark regeneration cycles, respectively. According to the test results and renewal conclusions, this study proposed a reasonable idea for constructing the prediction equation of referential biomass fuels’ 14C activity. Following this equation, the biomass fuels’ 14C activities of biomass direct-fired power stations at different Chinese cities were obtained.

Microhabitat orientation and structure and the presence of conspecifics may strongly influence the choice of habitat. We studied how these variables influence retreat- and nest-site selection in gravid females of a globally successful invasive species, the Asian house gecko (Hemidactylus frenatus). When provided with various substrates (vertical and horizontal ceramic tiles, vertical and horizontal plywood tiles, horizontal bark over leaf litter, vertical bark over a log, and sand) gravid female geckos preferred to retreat to, and nest in, materials with crevices commonly found in urban habitats. When housed alone, gravid females most frequently retreated to vertical ceramic tile or wooden crevices, and 66.7% nested in vertical ceramic tiles. When housed with two other conspecifics, gravid females most frequently retreated to vertical ceramic tiles, but selected a wider range of nest sites. Overall, gravid geckos housed alone typically nested in the same substrates that they used as diurnal retreats; when housed in groups, however, females oviposited in locations different from those they selected as retreats. Thus, H. frenatus females use a wider range of substrates when conspecifics are present. Invasion success in this species might be driven, in part, by preferences for retreat and nest substrates that are common in human-dominated habitats.

Mixing tree species could be a silviculture model that allows early harvest of short-rotation trees, while longer-rotation crop trees remain in the stand. We examined the effects on growth ...

Salvage logging is one of most frequently applied management responses to forest disturbances world‐wide. As forest disturbances are increasing, so too is the application of salvage logging, yet its effects on ecosystems remains incompletely understood. In the Norway spruce (Picea abies (L.) Karst.) forests of Europe, salvaging of windfelled trees is inter alia applied to reduce the risk of bark beetle outbreaks (mainly Ips typographus L.). By preventing further disturbances, salvage logging can conserve live tree carbon (C) in forest landscapes. At the same time salvage logging reduces C stocks in detrital pools via the extraction of disturbed trees, its net effect thus remains unclear. We used the forest landscape model iLand to explore the effect of a wide range of salvaging intensities on (a) subsequent bark beetle outbreaks, and (b) landscape‐scale forest C stocks in a Norway spruce‐dominated production forest in Slovakia under past and future climatic conditions. Climate change resulted in a two‐ to three‐fold increase in bark beetle disturbances throughout the 21st century in our simulations. We found that removing >95% of disturbed trees can effectively buffer the effect of increasing disturbances, dampening bark beetle infestations and increasing live tree C. Total ecosystem C followed a U‐shaped pattern over salvaging intensity, with highest values in no salvage and 100% salvage scenarios. However, realistic rates of salvaging (

Studies of the diversity of economically valuable traits in forest tree species are of great interest not only for forest selection and practical silviculture, but also important as a general biological problem. Among the objects of attention of breeders, a special place is occupied by cone-bearing species such as Siberian stone pine. Its cultivation through the forest tree plantations for wood and for cone-bearing will allow in the future to reduce the damage for natural ecosystems significantly. The purpose of this work was to analyze the structure of diversity in growth and generative development of the Siberian stone pine crown on a specially created plantation, where a low level of natural selection makes it possible to more efficiently select for early reproduction, growth and seed productivity. This plantation is located in the south of the area (Western Siberia, south of Tomsk region). It was created from stone pine seeds of the local population, that were sown in 1977 as forest crops with standard density (0,75 х 3 м). At the age of 10, they were planted out at a distance of 8 x 8 m. The vegetative and generative development of 89 trees aged 40 years was analyzed. We used a retrospective method that allows reconstructing of the tree organogenesis and growth on the scars on the bark of the shoots. The start of sexual reproduction has been reconstructed; a comparative characteristic of the vegetative and generative development of the tree crown has been carried out. The results show that, in general, the initial idea of the dependence of the efficiency of selection on the conditions in which the trees were formed is confirmed. In the natural dense stands, many of the leader trees in cone-bearing, which we found in our study, could fall behind due to slow growth and did not live to reproductive age. On the plantation where sparse tree planting was applied, they survived and became the leaders in cone-bearing. Early start of reproduction, even under conditions of sparse tree planting, is positively correlated with the growth rate in the pre-generative period of ontogenesis (r = + 0.65). The level of variations in the generative development of trees was much higher than in the vegetative one. The abundance of male shoots in the crown and the relative length of the male generative zone of crown were determined primarily by the height of the trees. On the contrary, the active growth of the tree in height did not have a noticeable influence on the development of the female shoots and the female generative zone of crown. Contrasting differences in the traits of male and female crown development with growth traits are very interesting result, in our opinion. Tall trees with a narrow crown are most promising for pollen productivity breeding, since they have a longer male generative zone and because of this they have more male shoots in the crown. Trees with a broad crown are promising for seed production breeding. Although seed productivity is not in all cases a direct function of the size of the crown, but depends on the specific genotype of the tree. This is confirmed by the fact that in each group (high, medium and low trees) there are individuals of high-cone-bearing and low-cone-bearing, which is promising for seed production breeding in groups of different growth levels. Using the calculated relative traits «1 m2 of the area of the horizontal projection of the crown onto the ground surface» made it possible to select the best trees for seed production (combining the minimum size of the crown with the number of cones per unit area of the crown) and growth (combining greater height and narrow crown).For citation: Velisevich S.N., Popov A.V. Pattern of diversity in the vegetative and generative crown structure of the siberian stone pine on a seed orchard with sparse tree planting. Lesnoy Zhurnal [Forestry Journal], 2019, no. 5, pp. 35–47. DOI: 10.17238/issn0536-1036.2019.5.35Funding: This work is supported by the Russian Science Foundation under grant no. 18-16-00058. The article is published within the framework of implementation of the scientific journals development program in 2019, based on proceedings of XIX International conference of the young scholars “Forests of Euro-Asia – The Southern Ural” (August 25-30, 2019. Chelyabinsk).

Drought has promoted large-scale, insect-induced tree mortality in recent years, with severe consequences for ecosystem function, atmospheric processes, sustainable resources and global biogeochemical cycles. However, the physiological linkages among drought, tree defences, and insect outbreaks are still uncertain, hindering our ability to accurately predict tree mortality under on-going climate change. Here we propose an interdisciplinary research agenda for addressing these crucial knowledge gaps. Our framework includes field manipulations, laboratory experiments, and modelling of insect and vegetation dynamics, and focuses on how drought affects interactions between conifer trees and bark beetles. We build upon existing theory and examine several key assumptions: (1) there is a trade-off in tree carbon investment between primary and secondary metabolites (e.g. growth vs defence); (2) secondary metabolites are one of the main component of tree defence against bark beetles and associated microbes; and (3) implementing conifer-bark beetle interactions in current models improves predictions of forest disturbance in a changing climate. Our framework provides guidance for addressing a major shortcoming in current implementations of large-scale vegetation models, the under-representation of insect-induced tree mortality.

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.

The taxonomic composition has been explored and the geographical analysis of P. nigra has been carried out in the street plantations of the City of Uman. To assess the feasibility of introducing a particular species into a particular area, along with its adaptive index, the preservation of those economic and valuable features, which are in the area of natural distribution and due to which it is desirable to cultivate, is of particular importance. On the basis of age parameters of the diameter and height of individual specimens, the high resistance of plants to the complicated conditions of the urbanized environment was noted and the prospect of using the species was established, under the influence of numerous anthropogenic factors on it. The increased interest in introduced plants in landscaping is due to the fact that in urban environments they are more stable and more durable than local species. The results show that all investigated P. nigra plants have high viability indicators and belong to the first group of availability. The significance of acclimatization numbers proves the promise of the introduction of P. nigra and the success of acclimatization in urban environments. In assessing the decorative qualities of P. nigra, it was basically found to stand out on the background of other species with its compact oval or cone crown, dark grey with different shades of cracked bark and long dark green needles. Due to these qualities, it retains an attractive appearance throughout the year, even in the winter. On the basis of the obtained results, the total annual decorative index of the main features of P. nigra is 4 points. It is established that medieval trees dominate in the age structure of street plantations of the city of Uman. Young trees under the age of 10 are absent at all, which suggests a low level of works for landscaping. According to the results of the evaluation of the success of P. nigra introduction in the urbanized environment, it is classified in the first group of promising plants, the degree of successful acclimatization is good, which indicates the normal acclimatization of this plant in the area of introduction. Thanks to its high decorative qualities, as well as its durability and unpretentiousness to the growth conditions, P. nigra perfectly adorns the streets of the city. It is grown both as a solitaire, and in combination with other plant species.

Dolomite and a micronutrient fertilizer are routinely incorporated into a pine bark-based soilless substrate when producing containerized nursery crops, yet the effect of these amendments on phosphorus (P) is not well understood. The objective of this research was to determine the effect of dolomite and micronutrient fertilizer amendments on P partitioning among four P fractions (i.e., orthophosphate-P EOM non-orthophosphate dissolved P [NODP], total dissolved P [TDP], and particulate P (PPJ) and to model potential P species in leachate of pine bark substrate. Amendment treatments incorporated into bark at experiment initiation included (1) a control (no fertilizer, dolomite, or micronutrient fertilizer), (2) controlled-release fertilizer (CRF), (3) CRF and dolomite, (4) CRF and micronutrient fertilizer, or (5) CRF, dolomite, and micronutrient fertilizer. Phosphorus fractions in leachate of irrigated pine bark columns were determined at eight sampling times over 48 days. Amending pine bark with dolomite and micronutrient fertilizer reduced leachate OP concentrations by 70% when averaged across sampling dates primarily due to retention of OP in the substrate by dolomite. The NODP fraction was unaffected by amendments, and the response of TDP was similar to that of OP. Particulate P was present throughout the study and was strongly correlated particulate Fe and DOC concentrations. Visual MINTEQ indicated MnHPO4 and Ca-5(PO4)(3)(OH) were consistently saturated with respect to their solid phase in treatments containing CRF. Results of this study suggest amending pine bark with dolomite and micronutrients is a best management practice for reducing P leaching from containerized nurseries. Virginia Agricultural Experiment Station of the National Institute of Food and Agriculture [SCRI 2014-51181-22372]; Hatch Program of the National Institute of Food and Agriculture [SCRI 2014-51181-22372]; US Dep. of Agriculture; Horticultural Research Institute; Virginia Nursery and Landscape Association The authors thank Julie Brindley, Velva Groover, Anna Birnbaum, and Doug Sturtz for technical assistance, as well as Pacific Organics for donating pine bark for this research. Funding was provided by the Virginia Agricultural Experiment Station and the Hatch Program of the National Institute of Food and Agriculture (including SCRI 2014-51181-22372), the US Dep. of Agriculture, the Horticultural Research Institute, and the Virginia Nursery and Landscape Association. Public domain – authored by a U.S. government employee

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.

The southeastern U.S. is considered the “wood-basket” of the world where loblolly pine (Pinus taeda L.) plantations provide tremendous ecological and economic benefits to the region. These plantations are susceptible to various natural and anthropogenic abiotic and biotic stressors and disturbances. The southern pine engravers, Ips avulsus (Eichhoff), I. calligraphus (Germar), and I. grandicollis (Eichhoff), are considered secondary colonizers of stressed, damaged, and dying loblolly pines. However, they may undergo outbreaks and colonize live pine hosts if environmental conditions cause physiological stress to trees. In 2016, >230 concurrent Ips infestations >2 ha in size were documented in Georgia, U.S., reportedly due to severe drought. In these forests, prescribed burning is often conducted every 2–3 years to reduce fuel-loads, improve wildlife habitat, and manage understory vegetation. However, the effects of low-severity prescribed fire on active southern Ips infestations are unknown; fire may exacerbate or alleviate beetle outbreaks. Our objectives were to: (1) compare Ips infestations between burned and unburned sites to determine the short-term effects of prescribed fire on loblolly pine mortality; and (2) determine which site-level and tree-level variables were the best predictors of short-term levels of tree mortality. We monitored 838 pines on ten sites for eight months following prescribed fire in spring 2017. Overall, 69 (8%) trees died with 3.6 times higher tree mortality on unburned sites, and a higher probability of survival on burned sites. At the site-level, binomial logistic regression models including treatment (unburned versus burned) and time since burn were the best predictors of loblolly pine mortality. At the tree-level, model selection showed that treatment, crown mortality level (1–5), Ips activity level (none, low, medium, and high), and tree diameter provided the best predictions of mortality. Prescribed burning may thus help alleviate pest pressure and increase tree resilience in loblolly pine forests in the southeastern U.S.

Debarking systems and strategies are used to increase the value of woody biomass by separating wood and bark into two value-added product streams. Several debarking methods have been used for the removal of bark from wood. The selection of a debarking method is often based on the wood type and its end use. Debarking methods discussed briefly in this review include drum debarking, ring debarking, cradle debarking, chain flail debarking, high-pressure water jet debarking, compression debarking, and biodebarking. The performance of these debarking methods is highly dependent on operational parameters of machines, properties and type of woody biomass, and pretreatments. A universal applicable mechanistic model of the debarking process would be especially valuable for the development and optimization of debarking systems. In this respect, the competing objectives of high bark removal, low wood damage, high throughput, and low energy must be balanced against one another to arrive at a truly optimized approach. Wood-bark bond strength plays a vital role in impacting the effectiveness and efficiency of debarking technology. Thus, it is important to understand how mechanical properties of the wood-bark interface are influenced by different factors. Key factors that affect the wood-bark bond strength include MC, harvest season, wood species, temperature, and direction of applied load. The likely reason why MC affects the wood-bark adhesion strength is that the constituent elements of primary plant cell walls (cellulose, hemicellulose, and pectin) behave differently when they are exposed to water molecules. For example, there is negligible change in the length if cellulose microfibrils when exposed to water molecules. However, characteristics of hemicellulose and pectin behave differently than cellulose when they contact with water molecules. Also, the difference in the adhesion strength of wood-bark bond among varieties of woody plants is possibly due to the difference in density of cross linkages of homogalacturonan pectin by Ca2., and arabinan and galactan side chains of pectin. The relevance of this information to the debarking process is discussed.

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.

Since the global financial crisis, the Anglo-American banking sector has been hit by revelation after revelation of mis-selling, fraud, and collusion. In response, state managers in the US and the ...

Human activity is one of the three main drivers of environmental changes in the mountains. Its influence on mountain natural environment is characterized by great spatiotemporal diversity. In the Tatras human impact started in the 12 th -13 th centuries and was related to mining and animal grazing, followed by metallurgy in the 18 th century. These activities developed in the 15 th -16 th and with the climax in the 18 th -19 th , except for the animal grazing which continued till the 1960s-1970s. Since the second half of the 19 th century tourism developed intensively. More than 3 million people per year visit the Polish part of the Tatras nowadays. Human activities, prior to tourism, were accompanied by a strong forest and dwarf pine shrubs extraction. They affected mainly relief and vegetation cover. Erosion in the slopes was triggered or intensified after deterioration of vegetation cover by grazing. Anthropogenic landforms like pits, mine roads, mine channels are still recognizable in landscape. Lowering of the upper forest and dwarf pine limits and changing of a natural structure of the forest into a monoculture are among the main influences on vegetation. Indirect effects of the changed forest structure are problems with bark beetles and windthrows. The later have been strongly affecting slope morphodynamics. Tourism-related impact manifest in gradual anthropogenic erosion along hiking trails. It is the major type of human impact n the Tatras now. The historical human impact until the 1960s-1970s was indeed spatial in nature. Currently, it is of a linear character or point-focused, and is relatively constant regarding particular locations.

Culturally modified trees (CMTs) provide tangible evidence of long-term forest use by Indigenous peoples. In Northwest Coast cedar forests, this record rarely spans beyond the last three centuries because older bark-harvest scars have been obscured through taphonomic processes such as natural healing and decay. Thus, archaeological visibility and identification are hindered. Here, I recover chronologies of ancient forest harvesting using a post-impact assessment methodology of targeting old-growth clear-cuts in southern Nuu-chah-nulth territories on the west coast of Vancouver Island, British Columbia, Canada. Bark-peeling scars are identified and dated in cross section by growth-ring patterns of recently logged trees. Approximately half of all bark-peeling scars are “embedded” inside healing lobes, suggesting at least half of all such CMTs are effectively invisible in standing forests. Features in these post-impact surveys predated those discovered in conventional archaeological impact assessments by a mean of almost a century. Additionally, one of the oldest continually used cultural forests ever recorded, dating to AD 908, is found in the Toquaht Nation traditional territory. These findings uncover measurable frequencies of cedar-bark harvesting generations prior to the contact period and reveal the inadequacy of heritage protections for old-growth cedar stands.

This study aimed to analyse the evolution of the quality of different types of forest residues and wood waste used for energy generation in a cogeneration plant, located in the city of Lages, Santa Catarina, Brazil. 4937 samples were analysed belonging to a database coming from a historical series, since the beginning of plant operation (2005–2015). The evaluated properties were moisture content, ash content and calorific value of the biomass. The results showed the there was a gradual and steady increase in the use biomass for energy generation in the study region. The three types of forest biomass purchased and used for energy generation in higher amounts in a cogeneration plant were the industrial chip, the bark and the sawdust. The mix analyses enabled the perception that there was an improvement in the quality of fuel supplied to company, evidenced by the decrease in moisture and ash content and consequent increase in the net calorific value (mean value 6612.84 kJ/kg). The moisture content of mix is also below (mean of 56.60%) the threshold value (60%) and it has been declining over the plant operation period, indicating progress in the processing and treatment of biomass for energy generation.

Background Nest construction is a key element of avian reproductive behaviour and the result is often a complex structure that is used for incubation of eggs, which represents an extended phenotype. It is known that nest construction is a plastic behaviour but the extent to which plasticity is observed in a single species with a wide geographical distribution is largely unknown. This study sought to better understand variation in nest size and composition across a very wide geographical area. The hypothesis suggested that location would affect size but not composition of nests of the European Pied Flycatcher (Ficedula hypoleuca). Methods Nests and reproductive data were collected from seventeen study sites, spread over 6° of latitude and 3.3° of longitude on the island of Great Britain. Dimensions of nests were measured before they were deconstructed to determine the masses and types materials used in the outer nest and the cup lining. Results Geographical variation was observed in base thickness of nests but not many other dimensions. Nests varied in composition but were mainly made of leaf, moss, bark, grass, root and fern. Moss was used more to the north and east of the study area compared with more leaf mass towards the south and west. The species of leaf and bark used in the nests varied between geographical locations. Additionally, the use of leaves or bark from a particular tree species did not reflect the incidence of the tree species in the immediate territory. Conclusions This study showed that nest composition was affected by geographical location over a wide area. Variation between nests at each location was high and so it was concluded that differences in nest composition reflect individual selection of materials but evidence is such that it remains unclear whether this is deliberate to fulfil a specific role in the nest, or simply opportunistic with birds simply picking up materials with the appropriate characteristics as they find them outside their nestbox.

Accurate estimates of tree stemwood volume are a fundamental requirement for sustainable forest management. As jack pine (Pinus banksiana Lamb.) and black spruce (Picea mariana Mill. BSP) are the p...

Introduction: In the United States of America, forest pests are associated with climate variability. Such studies are scarce in Mexico. Objectives: To create a data base of historical outbreaks of bark beetles and analyze their relationship with drought. Materials and methods: Historical records of outbreaks of bark beetles were obtained from official documents in Mexico, Guatemala, and Honduras. Dendroclimatic indices were used as a climate proxy. The relationship between pest outbreaks and climate was analyzed with the Superpose Epoch Analysis (SEA). Results and discussion: A database of 120 years (1895-2015) of bark beetle outbreaks was created. The most frequent species were Dendroctonus mexicanus Hopkins, Dendroctonus frontalis Zimmermann and Dendroctonus adjunctus Blandford. A total of 106 records of outbreaks in 15 states of Mexico were recorded during the period 1903-2015; 16 outbreaks in Guatemala during the period 1895-2013, and 15 outbreaks in Honduras during the period 1962-2015. Historically, outbreaks were recorded in years with below-average precipitation (550 mm) and have increased since 1970. The SEA determined that bark beetle outbreaks in Mexico, Guatemala and Honduras were recorded during dry years (P 0.05) of NINO 3 and PDSI (Palmer Drought Severity Index) and significant negative indices (P Conclusion: A significant relationship was determined between bark beetle outbreaks and drought conditions for the last 120 years.

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.

On 17 September 2017, I observed two Clark’s Nutcrackers (Nucifraga columbiana) from 8–10 m distance as they cached seeds in a stand of dead Whitebark Pines (Pinus albicaulis) at 2500 m elevation on Saint Mary Peak in the Bitterroot Mountains of Ravalli County, Montana. Over 5 minutes, the nutcrackers created 14 caches in seven different multi-trunk tree clusters in an area of about 50 m2. All caches appeared to be single Whitebark Pine seeds, positioned 2–5 m (mostly 3–4 m) above ground in dead trees. Of the 14 caches, three were placed under loose pieces of bark on a trunk (one) or large limb (two), and the remaining 11 were in encrustations of American Wolf Lichen (Letharia columbiana) growing on branches of the dead trees. Nutcrackers are known to sometimes cache seeds above ground in trees during the late summer and autumn harvest of pine seeds, but usually not to the exclusion of other microsites. The ground at the Montana site was covered by 7–9 cm of fresh snow that fell the previous day, which may have encouraged the nutcrackers to place all of their seed caches above ground in trees.

One of the first steps for expedient management of black locust stands is the evaluation of biotic production of aboveground phytomass. The purpose of the article is to develop the standards for the evaluation of the trunk components of the aboveground phytomass of black locust stands within Northern Steppe of Ukraine. In the presented work, the method of collecting and processing by prof. P.I. Lakyda are used for the receiving of results. The statistical processing, correlation analysis and the search of regression dependences of components of black locust trunk phytomass from stands biometric indices are made. The paper presents the results of mathematical modeling of the trunk phytomass components – trunk wood, trunk bark and trunk in the bark, as well as their dependence on the basic stand biometric characteristics (average height, average diameter, relative density). The study was conducted on 20 temporary trial plots in the forest of Dnipropetrovsk Region, which are in the jurisdiction of the State Agency of Forest Resources of Ukraine. A working data array has been formed that characterizes the components of the phytomass of the trunk, which is necessary for assessing the biotic production of artificial forest stands. Statistical and correlation analyzes of experimental data have been performed to define the nature of the distribution of the parameters studied and to ensure the adequacy of mathematical models. In the obtained mathematical models, feedback is observed among the components of the phytomass of the trunk with the average diameter of the stands. The relative density of the stands is statistically significant at introducing it into the equation simultaneously with the average diameter and average height of the stands. The conversion coefficient (the ratio of the phytomass of the trunk in the bark to the total stock of trunks in the bark) is calculated. Its value ranges from 0.37 to 1.12. The fragments of normative tables for the evaluation of the components of the trunks phytomass of black locust artificial stands with a relative density of 0.9 are given. The resulting normative trunk phytomass provide an opportunity to assess ecological and energy potential and calculate the carbon deposit in artificial black locust stands of the studied region.

The aim of the present study was to propose two ways for calculating the final price to be paid to suppliers of forest biomass based on the energy content of the fuel. Moisture content (MC) and ash content (AC) were considered quality indicators for a co-generation plant located in Lages, state of Santa Catarina, Brazil. Two models are proposed for the three biofuels most acquired by the plant (wood chips, sawdust and bark): Model 1, based on the Net Calorific Value (NCV) estimated considering the moisture content (MC) and ash content (AC) of the biomass; and Model 2, with the AC discounted from the dry weight of the biomass and subsequent estimate of the NCV considering the MC. The final price corresponded to the calculation between the weight and estimated NCV, with the suggestion of a bonus and discount for materials of better or worse quality, respectively. A significant reduction in biomass weight occurred after the ash discount, especially in the case of bark, which had a high AC. The price paid for kJ of biomass proved to be more coherent than the price per ton, since the ash and water content of the material is taken into account.

Gunnison's prairie dogs, Cynomys gunnisoni, frequently utter a repetitive series (a ‘bout’) of alarm calls (called ‘barks’) in response to a variety of terrestrial predators. Previous work has suggested that the structure of barks is finely tuned in ways that provide highly specific information about the identity of the predator. We re-evaluated these findings by presenting individually marked adult females with taxidermy mounts of three terrestrial predators of prairie dogs: a coyote, Canis latrans, a bobcat, Lynx rufus, and an American badger, Taxidea taxus, as well as one control stimulus (a cardboard box). Significant variation among individuals was evident from analyses of 10 measures associated with the general pattern of barking (e.g. latency to begin barking, bout duration, average number of barks/bout, overall bark rate, interbout interval) and also from eight structural features of individual barks (e.g. frequency and duration measures of the fundamental frequency band). When controlling for the identity of alarm callers, we found little evidence for differences in these same variables in response to different stimuli. We conclude that, like several other species of ground-dwelling squirrels, Gunnison's prairie dogs have an individually distinctive alarm call that does not differ for different predators. Our results conflict with earlier claims of extreme specificity in the alarm calls of Gunnison's prairie dogs.

Pines constitute a major tree crop, providing an array of products to several industrial sectors, but still holding significant new and unrealized potential worldwide. Among non-wood pine products resin is one of the best known and most exploited. Resin is a complex mixture of terpenes produced by specialized cells dedicated to tree defense. Terpenes from resin find various applications in industry, including chemicals, pharmaceuticals, agrochemicals, food additives, and bioenergy. More recent potential uses of resin products are biodegradable batteries and as components in the manufacturing of green plastics. Besides resin, other non-wood products from pines include needles, cones and bark, which can be used for landscaping, as well as plant cultivation substrates, biofuels and bioherbicides. Additional applications include medium-density fiberboard ingredients, metal biosorption composites, and production of nanofibrillated cellulose. The availability of industrial quantities of renewable non-wood biomass is a topic of significance due to the depletion of fossil-based raw materials and the respective environmental impact of their use. In this review, current and emerging applications of non-wood pine products are discussed, highlighting the importance of fully exploiting these forest resources in a sustainable fashion for maximum revenue generation.

In connection with differences in a height and development in the different site types the features of forming of structural components of above-ground phytomass of spruces forests stands are considered and their formalization is carried out on the basis of regressive analysis in the most prevailing site types. Object of the study – spruces forests stands in the prevailing site types of Polonynsky Range of the Ukrainian Carpathians. A research aim is a design of dependence of above-ground phytomass of spruces forests stands from their assessments indexes. Materials and methods. The authors used research data obtained in the result of setting 28 temporary trial plots on the territory of Polonynsky range of the Ukrainian Carpathians in order to study the dynamics of above-ground components of above-ground phytomass of spruces forets stands. Trial areas are stopped up on operating requirements, and the evaluation of closeness of components of above-ground phytomass of coniferous forests stands is researched followed on methodology of prof. P. I. Lakyda. To assess spruces stands phytomass we used the value of material density in the absolutely dry state. Results and discussions. A general tendency for researched site typs consists in the increase of tree trunk phytomass with the increase of mean values of trunk height and trunk diameter. In moist mixed broadleaved forest (C3) conditions the values of index at relative stocking of 0.7 are changed from 7.8-13.4 t×he-1 to 251-267 t×he-1, and in moist broadleaved forest (D3) conditions an increase takes place at the analogical values of middle high of from 8.0-13.4 t×he-1 to 270-286 t×he-1. A difference in the values of wood trunk phytomass to diminishes with the increase of mean values of trunk height and trunk diameter: from 0.6-2.8 % to 6.7-6.9 %. The values of trunk bark phytomass grow from 1.85-2.74 t×he-1 to 29.0-30.1 t×he-1 in C3 conditions, and from 1.69-2.28 t×he-1 to 25.8-26.9 t×he-1 in D3 conditions. For wood branches phytomass characteristic is an increase of difference with the increase of assessments indexes: in C3 conditions of value are higher and prevail analogical idexes in D3 conditions and they estimations are from 6.4-7.6 t×he-1 to 62.7-66.0 t×he-1 in C3 conditions and are from 5.1-6.1 t×he-1 to 52.7-55.6 t×he-1 in D3 conditions. The bark branches phytomass in C3 conditions grows from 0.63-0.66 t×he-1 to 3.45-3.47 t×he-1, and in D3 conditions at the analogical values of middle high – from 0.59-0.60 to 3.37-3.39 t×he-1. The values of needle phytomass in C3 conditions grow from 2.19-2.60 t×he-1 to 33.86-34.57 t×he-1 and in D3 conditions – from 1.88-2.24 to 29.50-30.11 t×he-1. The least difference between the values of leaves phytomass of beech forests stands is observed in sapling stands. The increase of values of general above-ground phytomass is traced in C3 conditions from 18.8-26.9 t×he-1 to 380-401 t×he-1, and in D3 conditions – from 17.2-34.6 t×he-1 to 381-402 t×he-1. Part of difference between the values of general above-ground phytomass in limits degrees of height trunk diminishes with the increase of middle trunk diameter. Conclusions. The worked out models of dependences adequately describe empiric material with the high level of approximation and characterized by sufficient statistical authenticity. On the basis of equalizations of models the complex of tables of estimation of the investigated components of above-ground phytomass is worked out in absolutely dry state.

The ancestral knowledge regarding the use of the leaves and bark of the ceibo to heal wounds, sores, blisters and control the bleeding of wounds by cuts, is a practice that has been lost especially in the rural and marginal urban area of the Portoviejo canton, being this way we worked in the recovery of the ancestral knowledge regarding the use of the leaf and bark of the royal ceibo tree, using the experimental method to elaborate the remedy and the plaster, a qualitative research was applied through an interview 3 farmers who have ancestral knowledge about remedies based on royal ceibo. The results include the recovery of ancestral knowledge to develop a remedy healing wounds, sores, blisters, and bleeding controller, tested on 30 students who performed agricultural practices in the field, exposed to the sun and heavy work in the field, with cuts and minor injuries , in which the remedy was applied based on cooked leaves of ceibo, and in 2 cases of wounds with bleeding the remedy of leaves and a bark plaster was applied, managing to stop the bleeding with the washing and promoting the healing of the wounds.

The incidence of salvage felling is a significant indicator of stands‘ health and stability. Health is mainly indicated by biotic and anthropogenic factors, while abiotic effects are primarily an indicator of a stand’s stability. All these factors influence each other and subsequently they can result in salvage felling. For the Czech Republic, there have been relevant data for the period since 1964. Actually, recent data cover approximately 70% of the Czech Republic´s area in the twenty-year period assessed in this text. During this period, the volume of salvage felling amounted to 89.2 million m3 which represents 28.4% of total felling in this period. The largest share is caused by abiotic effects (18.6%), next by biotic agents (9.6%) and anthropogenic are only responsible for 0.2%. In the last two years, the volume of salvage felling caused by biotic agents was higher than the volume of salvage felling caused by abiotic and anthropogenic agents for the first time. In terms of biotic agents, almost the whole volume is represented by bark beetle wood as a result of spruce stands infestation by the European spruce bark beetle – Ips typographus (L.) and double-spined bark beetle – Ips duplicatus (Sahl.), and to a small extent also by other species of bark beetles on spruce, pine and occasionally other wood tree species. In the last three years, mainly the incidence of the Ips typographus L., has concentrated in North Moravia and Silesia. Currently, it is also spreading in South Moravia and Bohemia and in districts along the state borders with Austria and Germany, with the most serious situation in this region being the one in the Bohemian-Moravian Highlands.

Global climate change also influences the forest damaging agents occurrence and thus a forest health. Forest trees that are damaged by agents are in managed forests processed by salvage felling. The amount of an annual salvage felling represents the occurrence of a damaging agents occurrence in a certain year. In 2015, the area of forests in Slovakia reached 2.014 mil. ha. Within the 20 years (from 1998 to 2017), the total felling reached 162.52 mil. m3, out of this 47.99 % were ascribed to a salvage felling. Abiotic agents were the most damaging agents (42.28 mil. m3 of damaged wood), out of it a wind was the most important one. Biotic damaging agents were the second important group (32.165 mil. m3), whereas bark beetles on spruce were the most important. The third group and the less damaging one was anthropogenic agents group (3.555 mil. m3) with an air pollution as the most important damaging agent. There was no statistically significant difference in the volume of processed trees within salvage felling caused by abiotic and biotic damaging agents. However, these two groups caused significantly higher damages than the third group of anthropogenic damaging agents. There were two major wind damages, Alžbeta in 2004 and Žofia in 2014 with damaged wood 5.3 mil. m3 and 5.2 mil. m3, respectively. They occurred in southern, central and northern part of Slovakia. As damaged wood was not processed from strict nature conservation areas, the secondary damaging agents, mostly Ips typographus on Norway spruce reproduced as much that after some years it cumulatively reached or even exceeded damages from those two major windthrows episodes.

El cuachalalate, (Amphipterigium adstringens), es una especie arbórea de la selva baja caducifolia, cuya corteza se utiliza desde tiempos prehispánicos en la medicina tradicional. Por ser uno de los productos de mayor demanda en la herbolaria mexicana y de importancia económica para las comunidades que viven en este ecosistema, en el INIFAP desde 1989 se han realizado investigaciones para mejorar su manejo lo que permite actualmente su aprovechamiento sustentable y legal. Sin embargo, el proceso de distribución aún no se había abordado, por eso se llevó a cabo el presente estudio, cuyo objetivo fue identificar las zonas de abastecimiento, las rutas de comercialización, los agentes que intervienen en la cadena de producción y los márgenes de ganancia entre eslabones. Para lograrlo, se hicieron observaciones de campo y una serie de entrevistas. Los resultados indican que las principales áreas oferentes de corteza son el estado de Morelos, la Mixteca Poblana y el norte de la cuenca del río Balsas; con una recolección promedio de 57.5 toneladas al año. Se detectaron cinco canales de comercialización ,y en todos ellos el recolector recibe la porción más pequeña del precio final. El porcentaje que corresponde a los acopiadores varía entre 6 y 33%. El margen del detallista de 20 a 97%, el cual es mayor cuando el número de intermediarios disminuye y el producto se procesa. Si la corteza se envasa, los responsables reciben 70% del precio final; mientras que los laboratorios obtienen 73%, aunque sus costos son más altos.

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.

Natural forest comprises approximately 78% of New Zealand’s total forest area and their dead wood carbon pools contribute to the national carbon balance reported under the United Nations Framework Convention on Climate Change. We investigate the accuracy of coarse woody debris (CWD) carbon stock estimates obtained from periodic inventories of New Zealand’s natural forest. Dimensions and decay classes of standing-dead spars, fallen logs and stumps over 10 cm diameter were assessed in permanent plots during two inventory cycles (2002–07 and 2009–14). Carbon in CWD was estimated by multiplying CWD volume with species-specific mean wood and bark density, a density modifier based on decay class, and the carbon fraction. The measured change in CWD between inventories was obtained by subtracting 2002–07 from 2009–14 mean CWD carbon stocks. This measured change in CWD carbon stocks was compared with the modelled change derived by applying a decay model to 2002–07 stocks to determine the losses from decay and adding inputs from the tree mortality recorded between the two measurement cycles. Estimates of CWD carbon stocks from field measurements were 19.9 and 19.5 tC ha−1 in 2002–07 and 2009–14 respectively, with a statistically non-significant change of −0.4 ± 0.6 tC ha−1 (95% C.I.) over the period between measurements implying that CWD carbon is in a steady state. However, the modelling approach gave a significant increase of 2.5 ± 0.7 tC ha−1, implying that CWD stocks are increasing. It appears likely that the primary reason for the discrepancy between the direct measurement and modelling approaches is that CWD carbon stocks are substantially underestimated using current measurement protocols used in the inventory of New Zealand’s natural forest. If CWD carbon stocks in New Zealand’s natural forests are approximately in balance as implied by the direct measurement of CWD stocks, CWD inputs from mortality would have to be balanced by losses from decay. For this to be true, the CWD pool would have to approximate 35.4 tC ha−1 which is 78% higher than its measured value.

Extensive outbreaks of bark beetles have affected not only large parts of coniferous forests in the Northern Hemisphere, but also — largely absent from global attention — native pine forests of Central America. As such outbreaks frequently spark management debates among residents, land managers, forest owners and the public, the social acceptance of bark beetle control measures has become crucial for modern land management. However, the sociological and psychological determinants of the preference for specific bark beetle control measures outside protected areas remain unclear. To determine the acceptability of bark beetle control measures in El Salvador, we assessed how demographic variables, attitude towards the bark beetle, education, and self-reported knowledge affected the preference for different bark beetle control measures in a survey of government employees and local forest owners using a quantitative questionnaire survey. Cumulative link mixed models revealed that the general preference for control measures increased with increasing self-reported knowledge about the bark beetle but decreased with increasing level of respondent education and an increasing positive attitude towards the bark beetle. Respondents generally preferred beetle control measures on small areas than on large areas. Preferences for control measures did not differ between government employees and forest owners, with controlled burning and chemical control significantly less accepted than stand thinning or salvage logging. We discuss the most preferred control measures considering recent scientific evidence of their efficacy and conclude that the current bark beetle outbreak should be controlled through logging of pines weakened by fire in the short-term and by stand thinning in the medium-term to prevent further outbreaks.

Historical management practices could have a strong effect on the current status of forests and therefore affect the potential for outbreaks of forest pests. We tested whether forest management history and forest tending of Norway spruce affects the potential for bark beetle outbreaks after large disturbances. We also assessed the effect of the proportion of spruce under epidemic situations and different altitudes. For this survey we used long-term data on sanitary felling and forest inventory data. Forest management history was defined by the change in the forest compared to the natural forest composition and was divided into four classes of change in tree species composition. We compared the proportion of spruce and sanitary felling because of bark beetles with the different classes of change in tree species composition. Forest tending was analyzed by looking at how the proportion of realized cut in relation to the planned cut affected sanitary felling. The analysis was done with Bayesian modeling including both spatial autocorrelation and random effects. There was a strong association between the change in the forest tree species composition and the proportion of Norway spruce and sanitary felling because of spruce bark beetles. Interactions were observed between epidemic periods, the proportion of Norway spruce and altitude. Altitude had a negative influence and the proportion of Norway spruce had a positive influence on sanitary felling. During epidemic periods, sanitary felling was amplified at lower altitudes and in areas with a higher proportion of Norway spruce. Furthermore, there was a negative association between the proportion of realized cut in relation to the planned cut and sanitary felling in periods after abiotic stress. It is therefore suggested that monocultures of Norway spruce should be converted to mixed forests and that maintenance of the forest should be improved to increase resistance to bark beetle outbreaks.

Sharing practice amongst arboriculturists is potentially a very valuable process for identifying commonalities in approaches to tree management and to identify where further research is nee...