Forestry Sciences

In 1933, Joaquim Vieira Natividade established an experimental field with oaks and related genera at Mata Nacional do Vimeiro, Portugal. This experimental area includes the only Portuguese plots with the hybrid Quercus x hispanica hybrid ‘Lucombeana’ (Quercus cerris x suber) with seeds obtained from the Cambridge Botanic Gardens.In 1962-1965, their offspring were included in this area.Those plots integrate an ex situ forest genetic resources, representing a unique population for understanding the structure, function and evolution of the genome (genomics) and its gene expression (transcriptomics). In all progenies, with approximately 60 years, it is evident the segregation for several phenotypic characteristics, specifically in the cork formation and in the leaf shape. Based on that, two projects were developed with this plant material. The first was focused on finding out the molecular basis responsible for the variation in cork and the other on association genetic studies.The aim o...

RESUMO -Este estudo teve por objetivos: quantificar o estoque de madeira para a produção de carvão e serraria em uma floresta de eucalipto; quantificar o estoque de carbono nos diferentes compartimentos da floresta; e avaliar economicamente alternativas de manejo, com vista à inserção de povoamentos florestais no mecanismo de desenvolvimento limpo e na venda de créditos de carbono. Para isso, realizou-se um inventário florestal em uma plantação de Eucalyptus grandis, com 6 anos de idade, no Município de Viçosa, Minas Gerais. Após as análises, verificou-se que: a) o fuste é o componente da árvore que mais contribui, em média, para o total de carbono da parte aérea (81,84%), seguido por casca (8,05%), galhos (7,74%) e folhas (2,57%); b) 47,7 toneladas de carbono por hectare estão estocadas na parte aérea das árvores; 14,71 nas raízes e 8,72 na manta orgânica, totalizando 71,13 toneladas de carbono por hectare; c) a produção de madeira somente para a venda de créditos de carbono, sem considerar o seu uso final, é economicamente viável, segundo critérios quantitativos de avaliação do projeto, se a tonelada de carbono for comercializada a preços maiores que US$ 10,07; e d) a venda de créditos de carbono torna o empreendimento ainda mais atrativo economicamente, sobretudo porque a receita é auferida no início do projeto.

At present, the production of wood composites mainly relies on the petrochemical-based and formaldehyde-based adhesives such as phenol-formaldehyde (PF) resins and urea-formaldehyde (UF) resins, which are non-renewable and therefore ultimately limited in supply.

Influence of wild ungulates on forest regeneration: overview for Switzerland Terminal shoots of tree saplings are part of the diet of chamois, roe and red deer, which in turn can affect forest regeneration. We investigated the current extent of browsing influence on the Swiss forest and the existence of regional differences. Our overview includes all available, regionally assessed data on the influence of roe deer, chamois and red deer in Switzerland, i.e. data of the fourth Swiss National Forest Inventory (NFI 2009/13) and data from the cantons derived from 1) representative sample plot inventories, 2) surveys in selected forest areas and 3) assessments by expert opinion. In the time period between approx. 2009 and 2014 no larger region of Switzerland stood out with respect to browsing influence. On the level of the ungulates home range or forest districts we found large differences in the browsing impact, but on at least two-thirds of the assessed forest area of Switzerland browsi...

A combined wood impregnation process including impregnation with a chromium-free wood preservative and oil treatment was evaluated with regard to leaching of copper during the oil process. Two different experimental setups make up the balance of copper content in oil, wood samples and condensate water, also taking different fixation times and process durations into account. Copper is sufficiently fixed after 24 hours, and leaching of copper into the oil is low. Increasing the oil process time does not lead to increased leaching. The hot oil treatment of impregnated wood under vacuum atmosphere is a fast drying method without major negative consequences for the impregnated copper. Prozessimmanente Kupferauswaschung während eines kombinierten Holzschutzverfahrens Zusammenfassung Ein kombiniertes Holzimprägnierverfahren, das eine Imprägnierung mit einem chromfreien Holzschutzmittel und eine anschließende Ölbehandlung miteinschließt wurde im Hinblick auf die Kupferausswaschung während des Ölprozesses untersucht. Zwei unterschiedliche Versuchsaufbauten bilanzieren den Kupfergehalt im Öl, in den Holzproben und im Kondensat unter der Berücksichtigung von verschiedenen Fixierungs-und Prozesszeiten. Nach 24 Stunden ist das Kupfer ausreichend

Forests on the northern slopes of the Rigi Mountain in central Switzerland ("Rigi-Nordlehne") have a key protective function against rockfall, erosion, landslides, flooding and debris flows. Forest management endeavours to guarantee that these forests can maintain their role in the long term. Thus multi-story canopies are favored, being resistant and resilient to natural disturbances such as windthrow. In addition, the mixture of tree species should conform to the guidelines of the national project "Sustainability and success monitoring in protection forests" (NaiS). However, at the present time an imbalance in tree species is evident in the regeneration layer, due to the considerable impact of browsing by wild ungulate populations in these beech and fir forests. To predict future mixtures of tree species, the spatially explicit model of forest development Rigfor was developed and applied to simulate and compare two scenarios of forest dynamics. The scenario "current browsing" suggests that silver fir cannot regenerate and that regeneration of maple and beech is greatly hindered. In the scenario "reduced browsing", however, a species mixture conforming to the national guidelines can be achieved in the regeneration layer. The simulations show that the amount of beech timber decreases whichever the scenario, while for the larger fir trees in diameter classes above 35 cm no changes are to be expected in the coming decades. However, from 2082 onwards a continuing high browsing rate would lead to the elimination of nearly all silver fir trees at the pole stage and in the long run silver fir may be completely eradicated from these stands.

The paper presents the proposals of improvement of the forest management planning principles aimed at efficient acquisition of data on the condition of forests and projected economic priorities with special emphasis on Natura 2000 areas, timber production for energy purposes, development of new techniques and technologies, carbon dioxide sequestration and climate changes. KEY WORDS forest planning, improvement of forest planning principles, sustainable development Directions of improvement of the forest management principles for pursuing sustainable forest economy

Papaya is a major fruit crop in tropical and subtropical regions worldwide. It has long been recognized as a nutritious and healthy fruit rich in vitamins A and C. Its small genome, unique aspects of nascent sex chromosomes, and agricultural importance are justifications for sequencing the genome. A female plant of the transgenic variety SunUp was selected for sequencing its genome to avoid the complication of assembling the XY chromosomes in a male or hermaphrodite plant. The draft genome revealed fewer genes than sequenced genomes of flowering plants, partly due to its lack of genome wide duplication since the ancient triplication event shared by eudicots. Most gene families have fewer members in papaya, including significantly fewer disease resistance genes. However, striking amplifications in gene number were found in some functional groups, including MADS-box genes, starch synthases, and volatiles that might affect the speciation and adaptation of papaya. The draft genome was used to clone a gene controlling fruit flesh color and to accelerate the construction of physical maps of sex chromosomes in papaya. Finishing the papaya genome and re-sequencing selected genomes in the family will further facilitate papaya improvement and the study of genome and sex chromosome evolution in angiosperms, particularly in Caricaceae. Keywords Carica papaya. Comparative genomics. Genome sequencing. Sex chromosomes A contribution to the Special Issue ''The genomes of the giants: a walk through the forest of tree genomes'' Communicated by A.

The forest tree breeding strategies used in Scandinavian and Baltic countries are discussed as regards breeding intensity and breeding systems, methods used for mating, testing, selection, and creation of propagule populations. Types of selection strategies and possible use of genetic estimates for evaluation of gain in tree breeding are discussed. Depending on species, the concepts and methods of tree improvement vary from country to country. First breeding cycle in most countries started with selection of plus trees, generating open pollinated or polycrossed progenies, long-term testing and backward selection. The subsequent breeding cycles or recurrent breeding are based mostly on recombination via open pollination or double-pair mating and on mixed forward selection model under Multiple Breeding Population System or Conventional unstructured system. Implications and options for Lithuanian forest tree breeding activity are presented in the light of this overview. Recurrent long-term breeding combined with gene conservation and based on Multiple Population Breeding System with open pollinated progeny testing would best suit breeding of most forest tree species in Lithuania. More intensive breeding options with double-pair mating can be used for Scots pine and silver birch and in combination with clone tests for Norway spruce. Number of subpopulations, the size of initial material, and intensity of forward selection will be chosen based on the economic importance of each species.

Species composition estimated from forest resource inventory (FRI) was validated using field data collected in 136 stands in Nipissing Forest (Ontario, Canada). FRI- and field-based species composition matched in 54% and 56% of cases using stand count and area coverage, respectively. Possible causes of discrepancy between FRI- and field-based species composition are discussed. Low level of agreement between FRI and field data indicated a need for more extensive studies on FRI validation prior to its use for forest management planning. Key words: forest resource inventory, FRI, forest unit, photo-interpretation, timber cruise

Aim: To calibrate a model of the relationship between bio-proxies (pollen, phytoliths and d 13 C of soil organic matter) and woody cover, measured as the leaf area index (LAI). This relationship, applied in palaeosequences, enables reconstruction of past savanna tree cover. Location: The samples are from tropical Africa. Modern soil samples are from the Central African Republic and past samples are from sediments of lakes in Senegal and Congo. Methods: We analysed the pollen and phytolith content and stable carbon isotope values of 17 soil samples taken from three short transects in the Central African Republic; LAI was measured on the same transects. The indices used were the AP/NAP ratio of arboreal (AP) to non-arboreal (NAP) pollen, the D/P ratio of ligneous dicotyledons (D) to Poaceae (P) phytoliths, and the d 13 C of soil organic matter, i.e. the 13 C/ 12 C ratio. Results: A multi-proxy model was calibrated. The best model included only a combination of pollen and phytolith as proxies, excluding organic matter d 13 C because of its long mean residence time in the soil. The model was then applied to two palaeosequences in Africa, and a time series of relative LAI changes was obtained, providing new information about vegetation changes. Conclusion: This model can be applied in palaeosequences to reconstruct relative time series of LAI in African savannas and can help interpret vegetation changes quantitatively. This approach is complementary to the description of pollen and phytolith assemblages. Bentaleb, I.

Os modelos polinomiais são mais difundidos no meio florestal brasileiro na descrição do perfil de árvores devido à sua facilidade de ajuste e precisão. O mesmo não ocorre com os modelos não-lineares, os quais possuem maior dificuldade de ajuste. Dentre os modelos não-lineares clássicos, na descrição do perfil, podem-se citar o de Gompertz, o Logístico e o de Weibull. Portanto, este estudo visou comparar os modelos lineares e não lineares para a descrição do perfil de árvores. As medidas de comparação foram o coeficiente de determinação (R²), o erro-padrão residual (s yx), o coeficiente de determinação corrigido (R²ajustado), o gráfico dos resíduos e a facilidade de ajuste. Os resultados ressaltaram que, dentre os modelos não-lineares, o que obteve melhor desempenho, de forma geral, foi o modelo Logístico, apesar de o modelo de Gompertz ser melhor em termos de erro-padrão residual. Nos modelos lineares, o polinômio proposto por Pires & Calegario foi superior aos demais. Ao comparar o...

El uso de agentes biológicos en la producción en vivero ha aflorado como un elemento que permite no sólo mejorar la calidad morfológica y fisiológica de las plantas, sino que también posibilitar un mayor éxito en el ámbito silvicultural de una plantación. Estos agentes biológicos requieren de un ambiente óptimo para crecer, asociarse y reproducirse. El objetivo de este estudio fue determinar la dependencia del pH y el medio de cultivo en el crecimiento in vitro de distintas cepas de Suillus luteus y Scleroderma citrinum asociadas a Pinus radiata y Eucalyptus globulus, respectivamente. El estudio se realizó en condiciones controladas de temperatura y humedad, disponiendo los inóculos en placas Petri con diferentes medios cultivo, evaluando parámetros de crecimiento y biomasa a los 38 días para S. luteus y 105 días para S. citrinum. Los resultados indican que tanto el medio de cultivo, el pH del medio, así como las cepas de cada especie estudiada, son determinantes en las respuestas d...

Urban forests are increasingly acknowledged as important areas for producing ecosystem services and maintaining ecosystem processes. In response, municipalities throughout North America have been adopting long-term plans to support strategic management of the urban forest. These plans have the potential to shape the urban forest for decades to come. Most management plans emphasize the planting of native trees, to improve ecological integrity and ecosystem services, and acknowledge the need for resident stewardship to help meet urban forestry goals. Residents’ support and action is crucial, since the majority of urban trees are located on residential property, yet it is unclear what residents’ attitudes and actions are regarding native trees. Using a case study of four municipalities in southern Ontario, Canada (two that have management plans that call for more native species plantings and two that do not), researchers administered a survey that explored residents’ attitudes and acti...

Our research seeks to expand the concept of urban environmental stewardship to include the everyday stewardship practices of urban nontimber forest products foragers. Ethnographic data from 58 urban foragers and 18 land stewards in the city of Seattle (USA) revealed that foragers reported using a variety of practices to enhance and minimize negative desirable species and their habitats. Many of these practices were identical to those practiced by restoration volunteers in formal programs and align with Seattle Parks Department management objectives. Foragers actively sought to learn more about what practices are sustainable; many mentored others in sustainable harvesting practices. Most foragers emphasized the importance of treating plants and their environment with respect. The land stewards voiced some concerns about foraging in city parks, but most were cautiously supportive of opening up the parks to foragers. The study results suggest that an opportunity exists for park managers to develop alliances with foragers so as to leverage foragers' everyday stewardship practices and accomplish some of their park restoration objectives. Doing so will require park managers to acknowledge the positive contributions that humans can to make novel ecosystems and foragers to develop or strengthen selfregulation norms.

Key message Hypocotyl semi-dwarfism in BP was only due to less cell number. Daylight was required to inhibit cell division in the mutant. ABA, IAA and cytokinins would be involved. Abstract Coffea arabica 'Laurina' is a natural mutant of Coffea arabica 'Bourbon' (B) and is known under the trade name 'Bourbon Pointu' (BP). Under daylight, the laurina mutation leads to pleiotropic effects, including semi-dwarf hypocotyls. At the opposite, semi-dwarfism of BP seedlings disappeared under darkness conditions. The first step was to describe the morphological impact of the mutation in seedlings growing under daylight by comparison with seedlings growing under darkness. As the hypocotyl length was mainly affected, the second step was to investigate histological modifications in the organ comparing B and BP seedlings growing under daylight. Result of this investigation indicated that the mutation does not impact on cell length. Moreover, cytometry analyses showed absence of endoreduplication. Actually, the mutation influenced the cell number and this effect appeared before the 40th day after sowing. The length difference of hypocotyls between B and BP was due to lower cell number in BP, indicating possible involvement of phytohormones. Investigations showed the decrease of cytokinin and auxin levels in BP compared to B, while the cytokinin/auxin ratio remained constant in both varieties. By contrast, abscisic acid content increased in BP. Concurrently these results indicate the lowering of cell division, due to the mutation. Keywords Coffea arabica 'Laurina' Á Hypocotyl semidwarfism Á Cell division Á Auxin Á Cytokinin Á Abscisic acid Communicated by F. Canovas.

Designing a fuel-sampling program that accurately and efficiently assesses fuel load at relevant spatial scales requires knowledge of each sample method’s strengths and weaknesses. We obtained loading values for six fuel components using five fuel load sampling techniques at five locations in western Montana, USA. The techniques included fixed-area plots, planar intersect, photoloads, a photoload macroplot, and a photo series. For each of the six fuels, we compared (1) the relative differences in load values among techniques and (2) the differences in load between each method and a reference sample. Totals from each method were rated for how much they deviated from totals for the reference in each fuel category. The planar-intersect method, which used 2.50 km of transects, was rated best overall for assessing the six fuels. Bootstrapping showed that at least 1.50 km of transect were needed to obtain estimates that approximate the reference sample. A newly developed photoload method,...

This study shows how information from routine inventory data can be used to predict juvenile tree height growth for trees ≤1.3 m using simple competition measures derived from such data. Actual 5year height increment is predicted by using: (1) the competition of the remaining overstorey, (2) the intra-and interspecies competition among the regeneration itself and (3) a modifier for the edge effect on incident light. For situations where no regeneration information is available, predictions were made of the occurrence of regeneration during the last 5 years using artificial neural networks. The results indicate that the probability of juvenile trees and the probability of a tree species per unit area are predictable with neural networks. The juvenile tree height growth analyses demonstrate that overstorey and inter-or intraspecific competition among the regeneration as well as the modifier for the edge effect on incident light were important to ensure accurate model predictions.

Recent enhancement of the pool of known molecular markers for avocado has allowed the construction of the first moderately dense genetic map for this species. Over 300 SSR markers have been characterized and 163 of these were used to construct a map from the reciprocal cross of two Florida cultivars 'Simmonds' and 'Tonnage'. One hundred thirty-five primer pairs amplified 163 usable loci with 20 primer pairs amplifying more than one locus. 'Tonnage' was heterozygous for 152 (93%) loci, whereas 'Simmonds' was heterozygous for 64 (39%). Null alleles were identified at several loci. Linkage maps were produced for both reciprocal crosses and combined to generate a composite linkage map for the F1 population of 715 individuals. The composite map contains 12 linkage groups. Linkage groups ranged in size from 157.3 cM (LG2) to 2.4 cM (LG12) and the number of loci mapped per group ranged from 29 (LG1) to two (LG12). The total map length was 1,087.4 cM. Only seven markers were observed to have segregation distortion (α ≤ 0.05) across both sub-composite (reciprocal) maps. Phenotypic data from traits of horticultural interest are currently being collected on this population with the ultimate goal of identifying useful quantitative trait loci and the development of a marker-assisted selection program.

It is known that dilute acid hydrolysis of cellulose results in yields not exceeding 60 65% of the potential glucose. All the models presented in the literature are based on the sequence cellulose ~ glucose ~ degradation products. The underlying assumption of this sequence is that the unconverted cellulose retains its chemical integrity with the extent of the hydrolysis reaction. In this paper we show that the unconverted cellulose is indeed modified during the hydrolytic treatment and cannot be chemically identified as cellulose as the reaction proceeds. This obviously limits the glucose yields and results in a major modification of the reaction sequence via dilute acid hydrolysis. Thermogravimetric analysis (TG), differential scanning calorimetry (DSC) and diffuse reflectance infrared (DRIFT) have been used to study the structural and chemical changes of the cellulosic residues as a function of the extent of hydrolysis.

The flora of the deciduous forests at the base of the north Estonian limestone escarpment is species rich, with an exceptionally high number of rare bryophyte species. Relationships between species richness of bryophyte and herb layers and biotic and environmental conditions were studied, using General Linear Mixed Models. Human disturbance (waste deposit, tree damage etc) was significantly negatively correlated with species richness of both plant layers. Soil nitrogen content was negatively and soil water retention positively correlated with bryophyte species richness, while herb richness was unrelated to soil factors. After eliminating the effects of environment, negative correlations in species richness and cover between the bryophyte and herb layers were discovered on finer scales (1 m 2 ), referring to biotic interactions. This relationship was obscured with the simple correlation analysis. On the other hand, the positive correlation in species pools between the bryophyte and herb layers (0.1 ha) was insignificant. The species pools of both bryophyte and herb layers were significantly positively correlated with the species richness of the tree layer. In summary, bryophyte and herb layer richness responded differently to environmental conditions, but human disturbance significantly decreased the richness of both layers. Due to the uniqueness and small area of these forests we recommend protection and restoration of disturbed sites. Nomenclature: Ingerpuu et al. (1994) for bryophytes, Leht (1999) for phanerogams. Abbreviation: GLMM = General Linear Mixed Model.

Estimates of tree age are important for making management decisions on the tree hollow resource because hollows suitable for fauna occur with greater frequency in older trees. The methods used to age trees vary with the practicalities of obtaining wood samples and the quality of the wood samples available. Ring counting is commonly used on smaller sample sizes when complete wood samples are available. When wood samples are incomplete, a combination of ring counting and extrapolation is often used. When no wood samples are obtained, growth models are generally used to estimate tree age. This paper uses all three methods, including three different growth models, to examine the accuracy of ageing trees. Simple regressions between tree age and diameter at breast height (over bark, dbh) provided the most accurate growth models at a site. Age estimates obtained from such models, however, had unacceptably large errors when few trees were used or when variable growth rates occurred. Under these circumstances, smaller errors margins were obtained from using a model based on tree dbh and site attributes than when averaging growth rates across sites. The estimated error in tree age estimates when using ring counting and extrapolation was about 10% of the tree age. The error of extrapolation increased with the amount of wood sample that was missing. Error margins were large for the oldest trees (average ± 42.4 y for trees > 350 y old) but less than ± 15 y for most (73%) of the trees estimated to be 100-300 y of age. These middle-aged trees are often the most useful to study when examining the rate of hollow production in eucalypts. Therefore, age estimates acquired in this way are generally accurate enough to be useful for making management decisions regarding the tree-hollow resource in production forests.

Conduziu-se este trabalho, com o objetivo de desenvolver uma metodologia de zoneamento ambiental para identificar áreas onde plantios de eucalipto possam ser desenvolvidos sem restrições ambientais e legais, utilizando o Município de Vassouras, no Estado do Rio de Janeiro, como estudo de caso. Foram considerados dados do meio físico, legislação ambiental, presença de áreas urbanas e o plano diretor municipal. Foram identificadas como zonas restritivas as áreas de preservação permanente, conforme a lei 4.771 de 1965 e suas alterações; as unidades de conservação e zonas de expansão industrial estabelecidas pelo plano diretor municipal; fragmentos florestais da mata atlântica e regiões próximas dos núcleos urbanos. Vassouras possui um território de 552 km², destes, aproximadamente 144 km² não apresentam nenhum tipo de restrição legal para o plantio de eucalipto, dos quais 97% estão atualmente ocupados por pastagens subutilizadas. Aproximadamente 93 % das áreas sem restrições apresentam...

L’agroforesterie consiste en l’association dans l’espace ou dans le temps d’un ligneux (arbre, palmier, liane) avec une ou plusieurs espèces annuelles ou pluriannuelles. Les systèmes agroforestiers se caractérisent ainsi par le degré de complexité des associations végétales qui les composent, et par leur structure spatiale, décrite en termes de strates verticales et de répartition horizontale (occupation des sols). Ces systèmes sont très variés, allant de l’association d’une culture pérenne plantée en lignes avec des cultures intercalaires à des systèmes complexes associant une multitude d’espèces végétales pérennes, pluriannuelles et annuelles dans une architecture multi -strates proche de celle d’une forêt naturelle, ces derniers systèmes étant communément appelés agroforêts. Ces sys-tèmes agroforestiers sont alors des plantations paysannes combinant des cultures de rente pérennes (hévéa, caféier, cacaoyer, cocotier…) avec d’autres plantes utiles comme des arbres à bois, des arbre...

Few long-term studies exist with integrated vegetation and soil composition data, coupled with detailed environmental driver records. Can changes in community composition in an upland grassland be identified by revisitation after a 40-year period and allow the main environmental drivers of change to be identified? Location: Snowdon, Wales, UK. Methods: Changes in plant community and soil composition were assessed by resurveying an upland Agrostis-Festuca grassland in 2008, 40 years after the original survey. PCA and ecological indicators were used to determine changes in plant community composition. Redundancy analysis (RDA) allowed the impact of soil chemical composition on the vegetation community to be assessed. Results: A significant shift in community composition was found between years. A 35% reduction in species richness and an increase in the grass:forb ratio, suggest significant ecosystem degradation. Indicator values suggest acidification of the community with an increased acidity preference of species recorded in 2008. However, soil pH measurements showed that soil pH had increased. RDA suggested that the main shifts in species composition were correlated with an increase in pH and a reduction in soil exchangeable base cation concentration. Clear ecosystem responses to climate, land-use change or nitrogen enrichment were not observed. Conclusions: Shifts in vegetation and soil composition are clearly identifiable after 40 years. The shifts in community composition are consistent with ecosystem degradation due to acidification during the period between surveys. Ecological indicator values and soil chemical composition displayed differing degrees of change. Whilst soils appear to be recovering from historic effects of sulphur deposition, vegetation community composition changes appear to lag behind those in soil chemistry.

Many developing southeast Asian governments are not capturing full rent from domestic forest logging operations. Such rent losses are commonly related to institutional failures, where informal institutions tend to dominate the control of forestry activity in spite of weakly enforced regulations. Our model is an attempt to add a new dimension to thinking about deforestation. We present a simple conceptual model, based on individual decisions rather than social or forest planning, which includes the human dynamics of participation in informal activity and the relatively slower ecological dynamics of changes in forest resources. We demonstrate how incumbent informal logging operations can be persistent, and that any spending aimed at replacing the informal institutions can only be successful if it pushes institutional settings past some threshold.

Oak decline is insufficiently described problem. Declining oaks are in various age and the most commonly observed symptoms of the disease include growth inhibition and buds mortality. The dieback occurs periodically, mainly because of the impact of abiotic factors (drought, frost and the lowering of the groundwater level). In this complex phenomenon the biological factors, including numerous species of Chromista (Chromalveolata) and fungi play important role as well. The list of pathogens responsible for the dieback includes numerous species of Pythium and Phytophthora, as well as Biscogniauxia, Discula, Pleurophoma, Botryosphaeria and Diplodia. Among other organisms responsible for the oak decline are fungi belonging to Fusarium species. The aim of this study was to investigate the species composition of pathogens colonizing the dying oak buds including undeveloped or dying shoots obtained from Łomża, Rudka and Czarna Biało− stocka forest districts (eastern Poland). Sampling of sym...

Juniperus trees were examined in a plantation located in Horning State Farm, near Plattsmouth in eastern Nebraska, USA. Trees were grown from seeds collected from 131 openpollinated families within 39 seed-zones in eastern redcedar (J. virginiana L.) and 25 open-pollinated families within 14 seedzones in Rocky Mountain juniper (J. scopulorum SARG.) from their native ranges in the Great Plains of USA. The plantation was established in spring 1980 to examine genetic variation among genotypes for resistance to Cercospora blight caused by Pseudocerospora juniperi (ELLIS and EVERH.) SUTTON and HODGES, comb. nov. (formerly Cercospora sequoiae var. juniperi), a major disease that threatens juniper survival east of the Rocky Mountains. All plantation plots were inoculated with P. juniperi in 1982, 1984, 1985, and 1986. Infection was scored in 1987. Kabatina tip blight caused by Kabatina juniperi SCHNEIDER and V. ARX, which occurred naturally, was scored also. Between the two juniper species, we found significant differences in survival and resistance to both diseases (P<0.05). All traits differed among seed-zones and among families within seed-zones of eastern redcedar (P<0.01). With Rocky Mountain juniper, variation was significant among seed-zones for survival (P<0.01), and among families within seed-zones for Cercospora blight and survival in 1994 (P<0.05). Heritabilities and genetic correlations were high for both disease resistance traits in eastern redcedar. Geographic patterns of genetic variation were identified; seed sources from southeastern collection sites of lower elevations tended to exhibit higher resistance to both diseases than seed sources from northwestern collection sites of higher elevations. Disease resistance traits were not correlated with height growth (ȊrȊ<0.20, P>0.05) for either species. The relationship between Cercospora blight resistance and survival in 1994 was significant (r = 0.59, P<0.05). Results indicate that Cercospora blight resistance in eastern redcedar can be improved by selecting resistant seed sources or families for direct reforestation programs or future breeding programs in eastern Nebraska. Additionally, Kabatina tip blight levels were lower on genotypes selected for resistance to Cercospora blight. Moreover, because resistance to Cercospora and Kabatina blights can be selected independently of height growth and survival, there is apparently no need to sacrifice growth and survival characteristics.

Between April 2000 and March 2007, the Canadian Ecology Centre – Forestry Research Partnership funded, directed, or catalyzed approximately 145 projects. Most of these focused on knowledge and data acquisition, providing a solid foundation for a series of sensitivity and gap analyses to determine whether a long-term goal of enhancing productivity on 6 forest management units in Ontario was achievable, and more importantly, sustainable. A research strategy provided the focus for knowledge and data acquisition and the partnership facilitated integrated research, development, transfer, and implementation. Here we provide an overview of this effort, which is expected to position forest managers of the 6 forests to apply an adaptive management process to increase understanding of the response of their forests to various forest management policies and practices in the future. The strategy and approach described could be useful to other jurisdictions aiming to more closely integrate forest...

This paper investigates the productivity and optimal rotation for economic timber management of Eucalyptus urophylla S.T Blake clones being planted in Northeast Vietnam in Fluvic Gleysol and Ferric Acrisol soils. In the first section of the paper, timber yield functions for all eucalyptus monoculture clones and seedlings are identified. Next, the biological optimum rotation period for maximizing sustained yield is calculated based on the yield functions for each soil type. In the last section, the economically optimal rotation (EOR) lengths for all clones and seedlings planted in the two types of soil are calculated using a modified Faustmann model. The results indicate that eucalypts in Fluvic Gleysol will produce larger timber yields than in Ferric Acrisol. Among the clones commonly planted in Northeast Vietnam, eucalyptus clones U16 and PN14 can yield the largest timber volumes in Fluvic Gleysol and Ferric Acrisol, respectively. Our EOR model reveals that EOR lengths of eucalyptus plantations in Northeast Vietnam are longer than the biological rotation time by 1-3 years under the governmentally subsidized credit scheme for rural households. If growers borrow from commercial and private entities, such rotation period will be substantially shortened and negative site values will appear in a number of cases. Nevertheless, wherever eucalyptus clones are economically qualified, their EOR length is longer than what is currently practiced. To capture the highest profits from eucalypt plantations, growers should extend their current farming business cycle of 7 years to 14-18 years under the subsidized credit scheme and to 10-12 years under the commercial borrowing interest rate. As increasing land use profitability is of great concern across the region, these findings are of practical importance for Vietnamese farmers in choosing clones, land lots, and economic optimal rotation for their farming businesses.

Methylal (7.6 g) and phosphorus pentoxide (2.84 g) were added to a stirred solution of eugenol (6) (1.64 g) in chloroform (20 ml, dried over phosphorus pentoxide) [cf. the method for the methoxymethylation of alcohols described by ]. After 2 h the reaction mixture was poured into ice-T. Iliefski et al.: Lignin-Related Cinnamaldehydes 479 Holzforschung / Vol. 57 / 2003 / No. 5

The aim of this work was to isolate a lectin from Myracrodruon urundeuva heartwood and to evaluate its antimicrobial activity against bacteria and fungi that attack plants, including woods. The lectin was isolated from heartwood through affinity chromatography on a chitin column monitored by hemagglutination assay. The lectin inhibited Gram-negative and Gram-positive bacteria and was more effective than antifungal Cercobin in growth inhibition of phytopathogenic fungi. The detected antimicrobial activity reveals the possible role of the lectin in the resistance of M. urundeuva heartwood against deteriorative biological agents. The M. urundeuva lectin is the first bioactive peptide found in heartwood, probably stored as a chemical protection against biodegradation.

RESUMO -O trabalho foi desenvolvido visando avaliar os parâmetros da pulverização em culturas arbóreas. A eficiência e a deposição de gotas sobre o alvo são importantes para elevar a rentabilidade na produção de madeira, diminuindo os riscos ambientais, e para a saúde do aplicador, aumentando a eficácia no combate de pragas e doenças. O objetivo deste trabalho foi avaliar os parâmetros operacionais de um pulverizador pneumático para aplicação em florestas adultas de eucalipto, através do estudo da densidade de gotas, da porcentagem de cobertura, do diâmetro da mediana volumétrica, do coeficiente de homogeneidade, da amplitude relativa e da uniformidade de distribuição volumétrica da calda. O pulverizador utilizado mostrou-se eficiente para a aplicação de agrotóxicos em árvores adultas de eucalipto. Observou-se que todos os tratamentos avaliados apresentaram densidade e tamanho de gotas satisfatórias para a pulverização. Quanto aos parâmetros porcentagem de cobertura, deposição e uniformidade de distribuição volumétrica, os melhores resultados ocorreram quando foram utilizados os índices volumétricos de 27 e 20,2 mL m 3 de dossel. O índice volumétrico de 20,2 mL m 3 de dossel foi o indicado para pulverização.

A comparison is made between a big-leaf model (i.e., without details of the canopy profile) and two multilayer models (i.e., with details of the canopy profile) to estimate daily canopy photosynthesis of a sugar maple (Acer saccharum Marsh.) stand. The first multilayer model uses the distribution of leaf area by leaf mass per unit area (LMA) classes, the observed relationships between the parameters of a photosynthesis--irradiance curve and LMA, and the relationship between relative irradiance and LMA to estimate canopy photosynthesis. When compared with this model, the big-leaf model underestimates daily canopy photosynthesis by 26% because of an assumed proportionality between photosynthetic capacity and relative irradiance, a proportionality that is inconsistent with our data. The bias induced by this assumption is reduced when the big-leaf model is compared with the second multilayer model which, in addition to the assumptions made for the first multilayer model, accounts for the sunlit and shaded fractions of leaf area. The residual bias is almost eliminated when the big-leaf model is run using a weekly averaged irradiance. It is likely, however, that this is the result of a compensating bias that, in this particular case, compensates for the initial bias introduced by the proportionality assumption. It is also shown that canopy photosynthesis can be represented by spatially inexplicit multilayer models that use leaf mass per area as a covariable to describe leaf characteristics and environment. Such models represent an interesting alternative to the biased big-leaf approach.