Phytophthora ×alni and Phytophthora lacustris associated with common alder decline in Central Portugal

Since the early 1990s, an emerging disease induced by the highly aggressive oomycete Phytophthora ×alni has caused widespread alder decline across Europe. In parallel, P. lacustris, a recently described species associated with riparian habitats, has been subject of increasing interest. A field survey conducted in 2014 showed high mortality rates in alder stands located in the riparian gallery along two rivers in Central Portugal. The pathogens isolated from necrotic alder stem base during this study were identified as P. ×alni and P. lacustris. This paper is the first to report the occurrence of P. lacustris in Portugal and presents the first finding of P. ×alni affecting mature trees in natural ecosystems located in Central Portugal.     

The unexpected northward migration of some species of insects in Central Europe and the climatic changes

From 1974 to 1983 a stable and considerable northward expansion of range (200 to 700 km) of some southern insects was detected. One of the most important causes of this phenomenon appears to be that winters were mild for several years. These data on expansion, involving several groups of insects, illuminate studies on the effects of the warming-up of the climate. The expansion range observed caused considerable economic problems, requiring regional and international remedial actions.

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Zusammenfassung Zwischen 1974 und 1983 konnte bei einigen südlichen Insektenarten eine ständige und wesentliche Nordexpansion (200–700 km) festgestellt werden. Eine der wichtigsten Ursachen des Phänomens scheint die Milde der Winter der letzten Jahre zu sein. Die Beobachtungen bestätigen einige sich mit Klimaerwärmungen befassende Studien. Die Expansion führte zu beträchtlichen wirtschaftlichen Sorgen und löste Gegenmaßnahmen auf internationaler Ebene aus.

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With 6 figures and one table     

Present and forecasted xeric climatic limits of beech and sessile oak distribution at low altitudes in Central Europe

• Introduction   

Xeric (trailing) forest range limits are particularly vulnerable to impacts of predicted climate change. Regional modelling studies contribute to the identification of potential local climatic threats and may support appropriate management strategies.     

北欧和中欧的原木价格

据《木材资源季刊》了解,由于制材部门对原木的需求量下降,2012年欧洲原木价格总体低于2011年。欧洲大陆的许多制材厂由于木材市场渐弱而被迫减产。北欧国家的原木价格下跌最严重,而东欧的价格却非常稳定,甚至在2012年底有小幅上涨的趋势。以美元计算,西欧大多主要原木市场的原木价格在过去2年里呈走低趋势,但是由于美     

Sustainable management of planted forests: some comparisons between Central Europe and the United States

Following the introduction of planned forestry and the regular high forest system more than 250 years ago, forests in Central Europe became increasingly shaped by plantation silviculture. Many natural woodlands were replaced by planted forests, and forest plantations are still being established through afforestation of extensive land areas. Nowadays, forests are managed for many different purposes, including wood production, recreation, ecological, cultural, and amenity values, biodiversity, and soil and groundwater protection. This brings new challenges to forest management and silviculture. To reach a sustainable forestry, in the sense of Brundtland (WCED 1987), we are now reshaping European forestry toward a more nature oriented silviculture. Maybe forestry in the United States and elsewhere can benefit from the mistakes made in Europe during the last two centuries and take a shortcut toward sustainable forestry.     

Involvement of Phytophthora spp. in chestnut decline in the Black Sea region of Turkey

Chestnut blight caused by Cryphonectria parasitica is a serious disease of Castanea sativa in the Black Sea region of Turkey. During disease surveys, dieback and decline symptoms were observed on trees without apparent blight and ink disease symptoms. Black necroses, similar to those caused by Phytophthora infections, were noted on some of the chestnut coppices and saplings in one nursery in Ordu and led to an investigation into this disease complex. Only symptomatic plants showing dieback symptoms were investigated. Soil samples together with fine roots were collected from two directions, north and north‐east, approximately 150 cm away from the main stems. Phytophthora spp. were baited with young chestnut leaves. Three Phytophthora spp., P. cambivora, P. cinnamomi and P. plurivora, were identified from 12 soil samples collected from 73 locations, while from the nurseries, only P. cinnamomi was obtained. Phytophthora cinnamomi was the most common species, obtained from seven locations in five provinces and from four nurseries having similar symptoms mentioned above in different locations. Phytophthora cambivora and P. plurivora were less frequently obtained, from three to two stands, respectively. Phytophthora cinnamomi and P. cambivora were the most aggressive species when inoculated at the stem base on 3‐year‐old chestnut saplings, killing six saplings of eight inoculated in 2 months. The three Phytophthora species were first recorded on chestnut in Black sea region of Turkey with the limited samples investigated in a large area about 150 000 ha chestnut forest.     

Incidence of Phytophthora species in oak forests in Austria and their possible involvement in oak decline

A survey on the occurrence of Phytophthora species in oak ecosystems in Austria was conducted from April to May 1999 and in June 2000. The investigations were carried out at 35 study sites distributed throughout the zone of oak forests in eastern Austria. Four oak species, including Quercus robur, Q. petraea, Q. cerris and Q. pubescens were considered in the survey. Rhizosphere soil samples were taken from sample trees, which consisted of healthy and declining trees as indicated by their crown transparency. Young oak leaflets were used as baits to recover Phytophthora species. The assemblage of Phytophthora spp. detected in Austrian oak forests consisted of five species, including Phytophthora quercina, P. citricola, P. gonapodyides, P. europaea and P. syringae. P. quercina and P. citricola were isolated from 11 and seven sites, respectively, and were thus the most common and most widely distributed species. The three other species were recovered only sporadically. P. citricola could be separated into two morphologically and genetically well‐characterized types (A and B). Phytophthora species, in particular the common P. quercina and P. citricola occurred on sites showing a wide variety of soil types, soil textures and moisture classes. There was mild evidence for connection between deteriorating crown status and the presence of Phytophthora spp. Furthermore, significant differences in contents of magnesium, as well as calcium, aluminium, nitrogen and carbon at different soil depths (0–10, 10–20 and 20–40 cm) were detected between Phytophthora‐infested and Phytophthora‐free sites. The results of the present study provide circumstantial evidence that Phytophthora species are involved in oak decline at certain sites in Austria.     

Analysing the Development of Small-Scale Forestry in Central and Eastern Europe

The current state and future prospects and challenges of small-scale forestry in Czech Republic, Hungary, Latvia, Lithuania, Poland, Romania, Slovakia, Slovenia and Ukraine are examined, and Q-methodology for stakeholder evaluation of forest sustainability and pro-market reforms is applied to an example from Ukraine. Small-scale forestry already provides multiple benefits to the countries in transition. However, these countries differ according to the maturity of the reforms, and the continuing process of transition is being delayed in some of them due to institutional weaknesses, e.g. the authority of government with insufficient involvement of rural communities in decision-making. The necessity of linking international and national sustainable forestry policy to management practices at a local level is especially evident in the countries where bottom-up small-scale adaptive forestry is only starting to catch up with the top-down sustainable forest management principles. The paper highlights the necessity of reconciliation of scientific and conventional knowledge for delivering sustainability objectives to small-scale forestry at a local level. It demonstrates that the social and economic pillars of sustainable forestry reform are of a particular importance for successful performance of small-scale forestry in the countries in transition, as is active involvement of stakeholders and local communities in decision-making and policy implementation.     

Causes of illegal logging in Central and Eastern Europe

A study has been undertaken to investigate the extent to which poverty is a determinant (final cause) of illegal logging, and to identify valid short-term policy variables for the control of illegal logging in Central and Eastern European (CEE) countries. The study identifies the main features of illegal logging and forest-related and rural-related conditions in the CEE region, and uses principal components analysis and cluster analysis to obtain a typology of the CEE region according to the above conditions. Regional differences within Lithuania and Romania are specifically examined. The analysis reveals that the occurrence of illegal logging is explained by poverty, but also by the reform on land ownership and by weak law enforcement. Implications of these results for policies to cope with the illegal logging phenomenon are discussed.     

Recent growth changes in Western European forests are driven by climate warming and structured across tree species climatic habitats

Key message

Recent growth changes (1980–2007) in Western European forests strongly vary across tree species, and range from +42% in mountain contexts to ?17% in Mediterranean contexts. These changes reveal recent climate warming footprint and are structured by species' temperature (?) and precipitation (+) growing conditions.

Context

Unprecedented climate warming impacts forests extensively, questioning the respective roles of climatic habitats and tree species in forest growth responses. National forest inventories ensure a repeated and spatially systematic monitoring of forests and form a unique contributing data source.

Aims

A primary aim of this paper was to estimate recent growth changes in eight major European tree species, in natural contexts ranging from mountain to Mediterranean. A second aim was to explore their association with species’ climatic habitat and contemporary climate change.

Methods

Using >315,000 tree increments measured in >25,000 NFI plots, temporal changes in stand basal area increment (BAI) were modelled. Indicators of climate normals and of recent climatic change were correlated to species BAI changes.

Results

BAI changes spanned from ?17 to +42% over 1980–2007 across species. BAI strongly increased for mountain species, showed moderate/no increase for generalist and temperate lowland species and declined for Mediterranean species. BAI changes were greater in colder/wetter contexts than in warmer/drier ones where declines were observed. This suggested a role for climate warming, further found more intense in colder contexts and strongly correlated with species BAI changes.

Conclusion

The predominant role of climate warming and species climatic habitat in recent growth changes is highlighted in Western Europe. Concern is raised for Mediterranean species, showing growth decreases in a warmer climate with stable precipitation.

     

中欧地区阔叶木需求强劲，但周边地区需求疲软

在对5月底参加在科隆举办的家具展的阔叶木贸易商的采访表明,欧洲阔叶木市场的情况反映整体经济状况。西班牙的代理商和进口商表示目前低贸易量的状况仍将持续。意大利代理商也表示目前的贸易情况不容乐观,由于国内市场消费量及在国外市场竞争力的下降,重要家具销售面临较大压力。相反,德国进口商对市场的前景表示乐观,而担心产品的供应量低于需求量。英国进口商表示年初市场状况比较合理,但市场的前景面临严     

Phytophthora alticola and P. boodjera associated with decline of young Eucalyptus smithii trees in Uruguay

Eucalyptus production mainly destined to cellulose pulp production has expanded strongly in the last 30 years in Uruguay. Eucalyptus smithii has recently emerged as a promising species for cellulose pulp production. However, an average of 40% of young trees die during the first and second summer of post-planting. In this study, 32 Phytophthora isolates were obtained from 132 E. smithii young trees with root and collar rot symptoms, confirming the association of Phytophthora to E. smithii decline. Based on phylogenetic analysis of ITS, TUB2, cox1 and HSP90 gene regions and phenotypical characteristics, two species belonging to the genera Phytophthora clade 4 were identified, P. alticola (96%) and P. boodjera (4%). Tested isolates of both species significantly reduced both shoot and root dry weights of inoculated E. smithii seedlings compared to control plants. To our best knowledge, this is the first time that P. alticola and P. boodjera are recovered from young symptomatic E. smithii trees in commercial plantations as well as the first time these species are found in the Americas.     

Root and aerial infections of Chamaecyparis lawsoniana by Phytophthora lateralis: a new threat for European countries

Phytophthora lateralis has been isolated from root and collar lesions in Port‐Orford Cedar (POC) trees (Chamaecyparis lawsoniana) in north‐western France (Brittany). These trees, planted in hedgerows, displayed symptoms similar to the typical symptoms of POC root disease. Until now, the disease has been found outside of the nurseries only in western North America. Aerial symptoms, not associated with root or collar infections, were also observed, and P. lateralis was isolated from branch lesions. Similar symptoms were previously observed only in one POC root disease site, located in the Pacific coast of Oregon where climatic conditions are similar to those occurring in Brittany. The reported aetiology as well as the morphological characteristics (deciduous sporangia) of P. lateralis suggests that this species could be air‐dispersed, as described for P. ramorum, a closely related species. This outbreak of P. lateralis in Brittany in farming landscapes associated with the aerial spread of this pathogen represents a new threat for European countries.     

Diplodia corticola and Phytophthora cinnamomi: the main pathogens involved in holm oak decline on Caprera Island (Italy)

Since 2008, severe and widespread tree decline and mortality has been observed at the main growing Quercus ilex L. (holm oak) forest on Caprera Island, Italy. To clarify the symptomatology and aetiology of this phenomenon, field surveys and isolations from symptomatic trees were carried out in summer 2010. Affected trees exhibited crown thinning, branch dieback, sunken cankers, epicormic shoots, exudates on branches and trunk, root losses and sudden death symptoms. Four fungal species belonging to Botryosphaeriaceae family, namely Botryosphaeria dothidea, Diplodia corticola, D. seriata and Neofusicoccum parvum, were isolated from cankers on trunk and branches, whereas three species of Phytophthora, namely P. cinnamomi, P. cryptogea and P. gonapodyides, were isolated from fine roots and rhizosphere soil samples. Isolates were identified using both morphological analysis and DNA‐based techniques. Pathogenicity trials on holm oak seedlings showed that all the isolated species are pathogenic. D. corticola proved to be the most aggressive species. Our results provide the first evidence for a combined involvement of D. corticola and P. cinnamomi in the aetiology of holm oak decline in Italy and suggest that these pathogens are not only important contributing factors in the onset of long‐term tree decline, but also may cause the rapid devastation of extensive oak ecosystems.     

Studies on the Health of Beech Trees in Surrey, England: Relationship between Winter Canopy Assessment by Roloff's Method and Twig Analysis

Trees and saplings of all sizes (total 229) were studied atthree amenity sites in Surrey representing mixed woodland, beechhigh forest and open parkland. Roloff's winter assessment ofthe twig pattern of growth demonstrated an underlying differencebetween the sites, which was consistent with an associationbetween greater deterioration and more exposure to climate extremesand pollutants. Trees showed deterioration with age but prematureageing was seen in 35–50-year-old parkland trees. Withinthe woodland the more exposed trees had worse scores. Quantitative twig analysis was carried out on twigs from theupper canopy of 19 trees and saplings. In the most severelysuppressed trees yearly growth declined from the 1976 drought.Subsidiary shoot development was markedly reduced in such treesand there were high numbers of distorted and acute angled shoots.The latter two characteristics increased with age with younghealthy trees having very few of these types of shoots, buttwo 35-year-old trees in open parkland showed premature ageingwith larger numbers of such shoots. Twig analysis defined categories of twig pattern according toage and deterioration levels. There was generally good correlationbetween these categories and the Roloff twig canopy score beforeanalysis or with canopy scores of similar sized neighbours.Objective criteria suggested for future studies were: (1) measurementof annual primary shoot growth; (2) total secondary shoot lengthrelative to a standard primary shoot length; (3) mean numberof subsidiary shoots per year; and (4) proportion of shootsgrowing at 40° or less.     

How geographic and climatic factors affect the adaptation of Douglas-fir provenances to the temperate continental climate zone in Europe

European Journal of Forest Research - The contribution of Douglas-fir (Df) to European forests is likely to increase as the species is a potential adaptation option to climate change. In this...     

Determining the climatic suitability of Eucalyptus dunnii for plantations in Australia,China and Central and South America

Climatic conditions within the naturaldistribution of Eucalyptus dunnii were determinedusing interpolated relationships developed forAustralia. Climatic interpolation relationships forAfrica, Central and South America and China as well asAustralia were then used to examine locations where E.dunnii has been successfully grown in trials and todetermine the species' climatic adaptability outsideits natural range. The original climatic profile wasrevised and maps were produced to show climaticallysuitable regions in Australia, China and Central andSouth America.     

A survey of the skidder fleet of Central,Eastern and Southern Europe

European Journal of Forest Research - As a generalization, harvested timber is extracted from forests either as trees or stems by skidders or as logs by forwarders. Coupled with harvesters,...