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The invasion of the Asian chestnut gall wasp Dryocosmus kuriphilus (ACGW) in Europe has caused serious biological and economic impacts on chestnut stands that have been partially solved with the introduction of the biological control agent Torymus sinensis. However, information concerning tree‐ring growth during the ACGW epidemic has been lacking so far. Using dendrochronology techniques, we analysed the impact of the ACGW on tree‐ring growth and the capacity of the chestnut tree to recover when biocontrol was achieved in seven sites covering the area of first detection and subsequent spread of the ACGW in Europe. In each site, a non‐target control species (i.e. trees not attacked by the ACGW) has been included as a reference in the analysis. Results show a reduction in the tree‐ring increment by 60% on average during the ACGW epidemic. Such effects were higher in the magnitude and longer in the duration when compared to other stresses such as insect defoliation or extreme summer droughts. Synthesis and applications. Marked reductions in radial growth were evident in the years of ACGW attack regardless of the age of the chestnut coppices. Since most of the trees only recovered to an almost normal growth rate after 3–4 years of biocontrol by T. sinensis, an immediate release of the antagonist at the first ACGW appearance is highly recommended. The consequences and perspectives of ACGW's attacks on the quality of the timber produced are also discussed.

The goal of this study is to assess the impact of different thinning approaches for coppice conversion into high forest of Turkey oak stands in Italy. The stand structure and the tree/shrub diversity were analyzed in 27 long-term monitoring plots from 7 experimental trials in the Colline Metallifere district (Tuscany, Central Italy) to verify the consistency of the original cultivation goals with the current stand structures. Three different approaches were applied from 1969 onwards: thinning from below, selective thinning, and no-management. Three indexes of specific diversity (Specific Richness, Shannon index and Importance Value) and two indexes of vertical diversity (Vertical Evenness and Coefficient of variation of tree height) were used to analyze and compare the outcome of management practices. The results showed a significantly higher dimensional variability and basal area, and a more complex vertical diversity in control plots and in the plots subject to selective thinning, as compared with plots subject to thinning from below. Tree species richness was high in all plots, independently of the thinning type applied. Based on our results, we suggest Turkey oak-dominated transitory stands to be initially managed by thinning from below, which is easy to be implemented and economically feasible. Selective thinning may be applied later with the aim of promoting sporadic but valuable tree species and increasing tree species diversity.

Traditional thinning and stand silviculture had positive effects on tree stability, stand efficiency and tree growth if compared to the lack of management. Nevertheless, the tree oriented silviculture has proven to be a type of management best meets the multifunctionality pourpouses required by forests today. In Italy beech high forests are generally managed with traditional thinning from below ascribable to stand silviculture; in the last decades tree oriented silviculture, an innovative management system is spreading in Europe. The aim of the study is to compare two thinning types applied in two localities of central Italy, in beech stands deriving from shelterwood system, aged 45-50 years: stand silviculture (SS), tree-silviculure (TS) and control (C). All trees were periodically measured in order to assess growth, mortality and production from 2008 onwards. Crop trees DBH, selected for each silvicultural approach, was annually measured while, an evaluation of the stem quality, crown development and stability were carried out between the 1st and last thinnings. Differences in vertical and horizontal diversity stand structures were assessed. Results pointed out similar growth rate at stand level; while a superior growth in diameter, in dimension of the crown and stability of the crop trees were observed in TS. The TS has proven to be the management option that best meets the multifunctionality required by forests today.

The potential ecological envelope of silver fir (Abies alba Mill.) based on its present distribution suggests a high suitability for moist rather than warm and dry environments. This contrasts with paleoecological evidence reporting its former presence at low elevations under meso-Mediterranean conditions. In this study, we evaluated the growth performance of silver fir at low elevation (20–60 m a.s.l.) under meso-Mediterranean climatic conditions in Tuscany (central Italy). We conducted a dendroecological analysis on Abies alba trees along a geomorphological gradient (from depression to upper slope conditions). Climate-growth relationships were assessed by means of correlations, response functions, pointer years, and superposed epoch analysis. Silver fir was found to grow and regenerate well in these stands mixed with evergreen (e.g., Quercus ilex L.) and thermophilous deciduous Mediterranean tree species (e.g., Q. cerris L.). Summer drought was the most growth-influencing factor, with immediate (i.e., current season) negative impacts on tree-ring widths (TRW). No significant impacts were observed in the four years following extreme summer droughts, but the TRW series (which started between the 1930s and 1950s) showed a growth decline since the mid-1990s that is likely drought-related. Our results show that, provided there is a sufficiently large soil water holding capacity, silver fir provenances exist which are able to withstand Mediterranean summer droughts, can naturally and regularly regenerate in these systems, and may even dominate over typical meso-Mediterranean species. As long as annual precipitation is not too low (i.e., >850 mm) and summer drought conditions not too extreme (i.e., less than three months), silver fir has thus the potential to thrive under warm Mediterranean conditions., Forest Ecology and Management, 498, ISSN:0378-1127, ISSN:1872-7042

Il contributo al convegno-incontro tecnico, riportata le più recenti esperienze di ricerca sui modelli colturali dell'arboricoltura da legno del pioppo, in alternativa alla monocoltura clonale che attualmente domina l'orientamento dei pioppicoltori, soprattutto nella Pianura Padana, con negative conseguenze ambientali e di sostenibilità produttiva

Site conditions and forest management affect dendrometric parameters of chestnut (Castanea sativa Mill.) coppices, but there is modest knowledge on the effect of stand dendrometric characters on physical and mechanical wood characteristics. The aim of this study was to verify these relationships in chestnut coppices that were 12–14 years old. Wood density, compression and bending strength, shrinkages were measured on shoots of five different stand in a vulcanic site in Monte Amiata (Central – Italy). Investigated stands differ in number of stools/ha and dominant height, diameter/basal area of the shoots. The main difference in the physical characters among the stands is density. The initial results of the study showed that physical, mechanical wood characters are more dependent by the shoot than by the site. There is a positive relationships between the number of stools/ha and density and a negative one among shoot dominant height and basal area with wood density. Spectroscopic profile by FTIR has not showed relevant differences among the stands. Wood anatomy has showed the breakpoint at cellular level.

The management of Italian chestnut coppices has gradually been suspended after World War II, causing a widespread overaging of the concerned stands. In recent years, the renewed interest in coppice wood products increased the need of a solid knowledge on the most suitable restoration practices of overaged coppices. In this context, a key issue is assuring a qualitative and abundant seed regeneration of the chestnut tree (Castanea sativa Miller) in order to substitute overaged stools. Open questions still exist however on the role of the standards (trees released after coppicing) and, in particular, on their interaction with the post-coppicing establishment of seed regeneration. In order to clarify these aspects, we applied different coppicing systems in overaged chestnut coppices so as to create a gradient of residual coverage ranging from full coverage left (no intervention) to simple coppicing (all trees cut, no standards released). The impact of different treatments on chestnut regeneration has been then assessed through field surveys in the second and fifth year post-coppicing, respectively. Chestnut seed regeneration promptly and abundantly established to guarantee the replacement of dead stools also in the simple coppicing. The post-coppicing pulse of chestnut seed regeneration mostly originated from the existing annual seed bank and it was concentrated in the first two years after the intervention, whereas seed inputs by standards or by adult trees at the forest edge played a secondary or negligible role from the third post-coppicing year onwards. Thus, the presence of standards did not benefit regeneration. Rather, it displayed a marked depressive effect on the growth rate of young chestnut seedlings and, under significant shading conditions, enhanced the establishment of shade-tolerant tree species. From a silvicultural point of view, simple coppicing of overaged chestnut coppices represents a valuable management option combining a rapid establishment of natural seed regeneration of chestnut with the resprout and development of the most vigorous stools.

Thinning intensity is an important factor affecting forest structure and density and influencing tree growth. The main objective of the study is to evaluate how the different intensity of thinning can influence, in the short and long term, the productivity and intrinsic water use efficiency (WUEi) of Quercus robur L., a widespread European species. Three thinning types of different intensity were applied in 14-year mixed plantation of Quercus robur L. growing with Alnus glutinosa (L) Gaertn., a N-fixing species, with an initial density of 625 trees/ha. A multidisciplinary approach was applied, coupling the tree-ring analyses with the measurements of stable isotopes of carbon and oxygen. Findings highlighted how the different conditions of light and competition, determined by the type and intensity of thinning, triggered different responses of Q. robur species in terms of growth and WUEi. Data suggested that the moderate selective thinning (31% reduction of total biomass) was not able to reduce the high competition for resources among individuals: this condition negatively influenced the trees growth. The presence of the N-fixing species, left after the thinning, was not able to counteract the negative effect of competition. A negative effect on productivity was recorded with the geometric thinning (62% reduction of total biomass). Indeed, this treatment resulted in an increase of asymmetry of the canopy (0.90 vs 0.83, respectively in pre- and post-thinning period), due to the partial crown competition from one side and with a consequent limitation of the photosynthetic activity of the trees. Finally, the very high selective thinning (75% reduction of total biomass) resulted to be the most appropriate management practice, as it guarantees positive effects both in terms of growth and intrinsic water use efficiency. The post thinning conditions determined high photosynthesis rates, an increase of productivity and a limited water loss.

[Key message]: The adoption of new silvicultural methods and approaches requires an understanding of the differencesbetween those and“old”or“conventional”approaches, along with extensive training to break previous knowledge bias., [Context]: Forestry is in transition towards ecosystem-based management, and new silvicultural approaches are appearingworldwide. However, the adoption of an alternative silvicultural approach is difficult in practice., [Aims]: We analyzed the effect of forestry background and demographic variables (gender and age) of 24 raters on the application of thesystemic approach (SA) and the conventional approach (CA) in the Northern Apennines (Italy) and compared this with tree markingperformed by experts., [Methods]: Data were analyzed as raters’departures from experts’selections at the stand and the individual tree level. Theprobability of tree selection was also calculated., [Results]: At the stand level, raters with forestry background performed the SA as if they were marking for crown thinning,whereas the CA was less intense than experts’crown thinning. Non-foresters differentiated poorly between the SA and the CA. Atthe individual tree level, background and gender affected tree selection., [Conclusion]: The adoption of the SA as a silvicultural system may be conditioned by previous knowledge. The differencebetween SA and CA remains unclear when it comes to non-foresters. Gender was a more important variable than age in selectingwhich trees would be harvested., LIFE+ PProSpoT (Policy and Protection of Sporadic tree species in Tuscany forests, LIFE09 ENV/IT/000087).

Aim of study: To verify the short rotation coppices (SRC) aboveground biomass production; to define the best planting intra-row spacing for walnut and poplar growth and wood production, with the last goal to assess the possibility of obtaining competitive yields in comparison to those produced by traditional monocultures. Area of study: Po Valley, municipality of Meleti (Northern Italy). Material and methods: A randomized block design with three replications was applied for the experimental design. The growth-monitoring activities started in 2009 and have continued for 5 years on the SRC, 10 years on poplar clone ˈI-214ˈ, whereas on common walnut they are still going on but only data concerning the twelfth year are reported in this work. The normality of distribution was evaluated for growth and yield data of species in the SRC model; all data were analysed with ANOVA; growth data were included in a linear mixed model analysis to evaluate the effect of age, spacing and their interaction, and the effect of SRC rows on growth and yield of poplar and walnut. Main results: After 5 years of cultivation under SRC system, biomass yields obtained from the poplar clone ˈAF2ˈ were 39.9 Mg ha-1, from the elm 31.9 Mg ha-1 and from the plane 14.8 Mg ha-1. After 10 years high timber production was obtained from poplar clone ˈI-214ˈ (average volume 98.2 m3 ha-1). After 12 years, walnut trees reached a diameter at breast height (DBH) of 17.8±0.2, 18.9±0.2 and 18.7±0.3 cm, respectively, for planting distances of 6, 7 and 8 m, and showed diameter increments of 1.5-2.0 cm yr-1. With these growth rates, walnut can reach a merchantable dimension within 25-30-years. Research highlights: Polycyclic wood plantations are a recent arboriculture model able to produce, on the same site, different assortments using various crop trees characterized by different growth rates and turnovers. This new type of mixed plantation is more environmentally sustainable compared to monoculture and allows diversification of production, obtaining continuous wood yields over the years (5, 10, 20, 30 years).

Coppice silviculture has a long tradition in Italy. Societal demands have led to the development of forest management techniques for integrating wood production with other kinds of forest uses and regulations have been issued to limit forest degradation. In Italy, 35% of the national forest cover is currently managed under coppice silvicultural systems that provide 66% of the annual wood production. Fuel-wood demand is increasing and a large amount of fuel-wood is currently imported in Italy. Modern coppice practices differ from those adopted in the past and may have a reduced impact on ecosystem characteristics and processes. Nevertheless, coppice silviculture has a bad reputation mostly on grounds that are beyond economic, technical and ecological rationales. Neither cessation of use nor a generalized conversion from coppice to high forest are likely to respond simultaneously to the many demands deriving from complex and articulated political and economic perspectives operating at global, European, national, regional and forest stand-level scales. Different approaches of modern silviculture to coppice successfully tested in Italy for more than a decade are illustrated. We propose to combine different options at the stand and sub-stand level, including either development without human interference or conversion to high forest, and to apply these approaches within the framework of novel forest management plans and regionally consistent administrative procedures. This bottom-up approach represents a potential solution to the socio-economic and environmental challenges affecting coppicing as a silvicultural system.

Tree-oriented silviculture is an innovative approach of forest management aimed at enhancing a limited number of early-selected crop trees whose growth is favored over the full rotation period by applying frequent thinning in their neighborhood. This approach was originally applied to high forests, but can also be applied to coppices to maintain or improve biodiversity by selecting valuable timber trees and/or minority species as target trees. The main limitation of this silvicultural option is the need of specialized and qualified operators in all the phases, from selection of crop trees to logging operations. In this study, experimental trials were established by the Forest Research Centre of Arezzo (Italy) to verify the suitability of this approach to different structural and enviromental conditions. In coppices characterized by fast growing species such as chestnut, tree-oriented silviculture has been applied to a limited number of crop trees (50-100 ha) to obtain more valuable and larger-sized assortments in a shorter rotation period, reducing at the same time the silvicultural costs. In mixed coppices, where the ordinary management (coppicing) was applied, the abandonment or the conversion into high forest gave rise to a progressive loss in terms of species composition. Contrastingly, thinning focused around a few (5-20) trees of sporadic species allowed to maintain a high level of biodiversity, and led to favorable conditions for growth and regeneration of these species.

Over the last decades, the abandonment of the traditional management due to many adverse factors caused a general aging of chestnut coppices; this led to an increased mortality of the chestnut stools and a consequent replacement with the entry of other species. Preservation and improvement of the chestnut coppice emphasize the importance of natural regeneration for future forest management: seed regeneration contributes to provide new stools for future coppice generations and promotes a proper development of the stand in terms of specific and structural diversity. In this study, we propose a method for investigating the relationship between density, diversity, development of natural regeneration and possible driving forces in terms of site conditions and stand parameters. At this purpose, a survey based on mixed sampling plots was conducted in different coppice systems (simple coppice, coppice with standards), 4÷8 years after the coppicing: measurements on stools, shoots and standards, as well as seed regeneration were carried out. Chestnut seed regeneration was characterized by taller individuals in simple coppice plots, even though the seedlings were fewer than those in coppice with standards treatment. Canopy cover and amount of standards, density of stools and resprouting shoots negatively influenced the establishment of chestnut seed regeneration: likewise, within the same treatment, plots with greater site index promoted the development of chestnut regeneration. The proposed methods allowed a characterization of the dynamics related to the natural regeneration of classical chestnut coppice systems, identifying the main controlling factors. Among them, factors modifiable by management, such as stand structure and amount of standards, offer forest managers multiple silvicultural options to control seed regeneration processes.

In view of the projected increases in the frequency and duration of drought events in the Mediterranean basin, a better understanding how differences in stand structure influence climate-growth relationships can improve and drive the conservation and management strategies for marginal forests in mountain areas. In this study, we examined the intra-annual variability of growth patterns and responses to climate of two maritime pine (Pinus pinaster Ait.) stands growing at contrasting tree densities at low elevation in northern Sardinia. A dendroclimatic analysis was used to assess the climate-growth relationships of these trees on monthly, seasonal and annual scales. The late spring and summer precipitations of the current year appeared to be the crucial climatic driver that encouraged the radial growth of the species in this mountain stand. However, summer drought was the primary climate constraint, exerting negative effects on P. pinaster growth. Summer Palmer drought severity index showed contrasting influence on latewood growth responses to drought conditions related to stand density, remaining significant also during the autumn months in the stand with the highest tree density. Our findings indicate that stands growing at high tree densities may experience more prolonged water shortages, especially during the late summer and early autumn months. Additionally, since the early 1980s, as precipitation has decreased, the influence of previous rainy years on radial growth has been highly significant in the stand with the lowest tree density. This result might suggests that these trees are able to utilize a greater amount of water reaching deeper soil horizons stored due to the previous rainy years, especially during periods of low precipitation.

In this contribution we present the results of a Swiss-Italian joint sylvicultural experiment to verify if and how the single-tree-oriented silviculture can be applied to chestnut coppices to enhance timber production for industry and structural timber. The study was carried out in five 7 to 17 years old, pure chestnut coppice stands growing on sites of medium to good fertility in central Italy and southern Switzerland. The single-tree-oriented silviculture (option A, 100-150 target trees per hectare) was compared to the stand-oriented silviculture (option B) and to the natural evolution (option C) in terms of growth performance (i.e. individual annual radial increment), stand stability and efficiency (namely leaf area index [LAI], incidence of game and gall wasp attacks, harvesting damages). Suitability of the different treatments has been evaluated on effective (Option A) and theoretical (Options B and C) target trees as selected at time of the first thinning. First results show a significant higher increment response of the target trees in option A compared to the two other silvicultural systems, and a general fast and dynamic recovery of canopy cover after the thinnings in both silvicultural treatments, but even more in the single-tree-oriented silviculture, where two thinnings were necessary within few years. Due to the short time since the arrival of the gall wasp at the experimental sites, no clear impact patterns have been detected. Nevertheless, the attack severity seems to be higher in the target trees of the A option. Damages caused at the stem base by red deer or harvesting operations were clearly higher in the option A, which may reduce the positive outcome of this slvicultural option.

This study is part of a LIFE+ project on marginal mountain ecosystem conservation. In five mixed European beech-silver fir forests of Central Italy (Tuscany and Marches), classified as priority habitats of the Natura 2000 Network, we analysed the climate–growth relationships of silver fir (Abies alba Mill.) along an altitudinal gradient. The aims of this study were: (i) to identify the main spatial patterns in the frequency domain of both silver fir growth and climate variables in five different sites and (ii) to detect the overall climate sensitivity of the target species through time. Multivariate analysis displayed groups of chronologies with similar growth patterns for each frequency band-pass, discriminating for altitude and geographical location. The spectral density of climate variables at seasonal scale displayed common spatial patterns during late-spring and summer months. In stands where fir grows in optimal conditions, the most significant growth responses to climate were the positive influence of late-spring and summer precipitations of the previous year and the negative effect of summer temperatures of both previous and current year, although decreasing during the last decades. On the other hand, the site at lowest altitude shows a low and not very consistent climate sensitivity as compared to the preferred altitudes. At the highest site (1375 m asl) the positive effect of previous year spring–summer precipitation and summer temperature of both previous and current year disappears. Results suggest that in the studied areas a water-use increase in summer is a possible response of silver fir to the significant reduction of spring precipitation and general temperature increase throughout the 20th century. These findings provide additional information on silver fir responses to climate variability at different altitudes, useful for calibrating silvicultural treatments to apply for conservation of sensitive ecosystems and of tree species in mountain areas.

Tree biomass plays a key role in sustainable forest management and in determining forest carbon stocks. Accurate estimates based on species-specific empirical data are necessary for regional and national inventories and forest carbon management. In this study, we obtained allometric relationships for volume and aboveground biomass for stone pine (Pinus pinea) based on empirical data collected in four coastal stands in Italy. Root sampling was also performed. The results enabled generalized equations for volume and aboveground biomass to be developed. However, an analysis also showed several differences in biomass allocation in stone pine resulting from different stand characteristics, emphasizing the importance of stand-dependent factors for adjusting regional or national biomass calculations. Biomass expansion factors were also provided. This study provides tools to help forest managers in quantifying volume and biomass, thereby contributing to the accurate estimation of carbon sequestration and stocks in stone pine stands in Italy.

Sensitivity to climate change and anthropogenic disturbance is a typical feature of Mediterranean forests, which grow under dynamic and manipulated environmental conditions. In this study, we examine stone pine (Pinus pinea L.) along the Tyrrhenian coast of Italy to analyse the tree-growth variability on a temporal scale and to evaluate the radial growth response to climate trends over the last century. The analysis of tree ring widths at the decadal and multidecadal scale, which were standardised to remove the age trend, showed primarily significant downward trends and time periods with lower growth rates. Characterised by a clear decline in tree ring widths, the two periods of 20 years from the mid-1920s and the early 1970s appeared to be the least favourables for tree growth. Precipitation was the main factor driving growth, and the effect was cumulative over consecutive years because of the increase in soil water content. Including the current year of ring formation, correlations between decline in precipitation and tree growth were greatest with 3-year precipitation sums. The shifting influence of winter rainfall on tree ring growth toward not significant values during the last decades, together with the lack of significant correlation between the current year’s precipitation and growth decline from the 1970s, might suggest an increasingly dependence on long periods of water supply to utilise the water content stored due to the previous rainy years. The negative effect on tree-growth decline of summer and early-fall temperatures appeared as a forcing influence related to long-term changes in climate rather than high-frequency climate fluctuations.

A dendroclimatic analysis was used to assess the climate-growth relationships of Abies alba Mill. over the last century in marginal populations of Central Italy. Tree-ring cores were collected in five mixed silver fir forests at low and high-elevation sites of the Apennines range in Tuscany and Marches. Regular and moving correlations functions were applied to tree-ring width series and monthly climate gridded data. Principal component analysis displayed groups of chronologies with similar growth patterns, discriminating for altitude and geographical location. Climate-growth relationships showed the positive influence of late-spring and summer precipitations and the negative effect of summer temperatures. Stands growing within the optimal altitude range for the species showed a positive and a decreasing negative influence of spring and summer temperatures, respectively. At the highest site (1375 m asl) the positive effect of previous year spring-summer precipitation and summer temperature of both previous and current year became scarce or null. Results suggest that the shifting influence of summer precipitation on tree-rings growth from July to August of the previous year is a possible response of silver fir to the significant reduction of spring precipitation and general temperature increase throughout the 20th century.

The chestnut timber chain in Tuscany is divided into two main production lines: posts and industrial timber. In the first case, regional manufacturing of raw material mostly covers the domestic needs. As for industrial uses, in spite of the high demand for quality timber, the scarce development and quality of production also affects the manufacturing stages. The main reason lies in the everlasting difficulty of supplying chestnut timber assortments for industrial purposes. The production is extremely inadequate, especially in terms of quality. The Italian raw material can be only partially qualified as industrial timber, because of the lack of suitable size and quality requirements. Accordingly, industrial timber is increasingly being imported from foreign markets. The aim of this paper is to assess whether the growth of local supply can be sustained by first-phase processing enterprises in terms of quality timber assortments. The survey analyzed the structure of several enterprises located on Monte Amiata (SI) and the Colline Metallifere (GR). Data necessary for gaining more knowledge about the first step in the timber-forest chain were acquired from questionnaires submitted to the owners of the firms operating in this sector. The information acquired included firm size, source of woody material, availability and annual quantity of wood sales, prices of assortments, and machinery and equipment owned by each firm. The interviews shed light on several aspects such as the interest in local woody material supply in spite of difficulties in sourcing the same. The sample consisted of small-sized enterprises, family-run entities, poorly equipped for machinery, mainly represented by posts marketed in the local area. As for the goal of this survey, it must be pointed out that the majority of firms processing chestnut timber are located on Monte Amiata, where chestnut stands are one of the main forest types; while in the Colline Metallifere, these firms focus more on oak species since chestnut plays a marginal role and no timber trading activity exists among the firms found in the two surveyed areas.

The canonical attributes of old-growth forests, their importance for management approaches fostering the development of structurally complex conditions are reported. The relict presence of primary forests led to withdraw from the regular silvicultural management patches of forests and assign them to a non-intervention regime. They have been referred to as “unmanaged forest reserves”. In this context, at mid 1900, A. Pavari established a network of 24 permanent plots at the purpose of “saving from anthropogenic disturbance and studying the natural evolutive pattern of different forest types to establish wellgrounded rules of management”. Most of plots set up by Pavari have nowadays lost their effectiveness because of various occurrences. Five plots are described here as for their numerical, structural and compositional dynamics. The recorded parameters draw systems that, even if far from equilibrium, show the occurrence of positive evolutive patterns. Differences to natural forests are, basically, the heritage of the previous multiple uses of forest soil and stand as well. On this basis, the component species have modified their presence in term of richness, evenness and dominance, depending on their auto-ecology,resistance or resilience. The long-term monitoring of primary forests and secondary systems left to the natural evolution finds out manifold, sound reasons today. The practice of ordinary management has been reduced greatly and the foreseeable trend is to increase further over the next period. According to its progress, many forests are experiencing a prolongation of the prearranged rotations and a post-cultivation phase is becoming the rule; stands are therefore getting older. Findings by old-growth forests and unmanaged forest areas monitoring will provide references for managing this diffuse condition.

Sensitivity to climate change and anthropogenic disturbance is a typical feature of Mediterranean forests growing under dynamic and manipulated environmental conditions. In the present study, a large sample of stone pines (Pinus pinea L.) was analyzed in five sites of Castelporziano and Castelfusano forests (Rome, central Italy) to assess tree-growth variability (1964–2009) with the aim to derive information on long-term climatic trends possibly reflected in the radial growth response. The multivariate exploratory analysis of tree ring widths, which were standardized to remove the age trend, showed a marked spatial variability among sites and a heterogeneous time pattern that allows for the classification of the investigated years into three homogeneous groups: 1964–1974, 1975–1997, and 1998–2009. The years 1975 and 1998 were identified as the candidate break points in the local climate regime. Coherence of the 1998 break point was verified by comparing two time intervals (1981–1997 and 1998–2011) of the meteorological time series of precipitation and temperatures available for Castelporziano station. Results indicate a significant shift toward aridity and warming in the area supporting the information obtained from the analysis of dendro-chronological time series. Implications of the spatio-temporal monitoring of climate variations through indirect sources are discussed in the light of conservation of the residual pristine forest of Castelporziano taken as a paradigmatic example for other Mediterranean coastal forests.

International audience; AbstractKey messageTraditional coppice conversion to high forest through periodic thinning requires a long period to attain the regeneration stage. We showed that anticipating seed cutting can accelerate the progression of the stands towards more adult stand conditions, compared with traditional management. The application of different active management options in the same landscape can contribute to increase landscape diversity.ContextIn southern European beech forests, coppice is a widespread management system, especially due to the past uses. The existence of large areas either abandoned or under protracted transitory stage raises questions concerning environmental and economic revenues related to the different management options.AimsWe evaluated the effectiveness of anticipating seed cutting in beech coppices to accelerate the coppice transition to high forest, compared with traditional management (periodic thinning) and natural evolution pattern (unthinned control).MethodsWe used an exploratory analysis of ecological variables related to structure, dynamics, and productivity of the stands (growth efficiency, leaf area index, litter production, transmittance, and canopy heterogeneity), which were monitored during 10 years in beech coppices in Central Italy.ResultsAnticipating seed cutting produced stronger modification in canopy structure, improving growth efficiency as a result of higher resource availability, supporting higher seed production which accelerated the progression of the stand towards more adult stand conditions, compared with traditional management and unthinned control.ConclusionThe application of different active management options can increase landscape heterogeneity under the conditions in which increasing landscape diversity represents a priority management issue, while simultaneously allowing environmental and economic revenues.

A preliminary analysis was made of growth trends in two silver fir forests in the Apennines in central Italy. The forests are closely located but were managed differently in the past. The aim was to verify the climatic variation over time, the influence of extreme events on radial growth and the role of silvicultural systems in defining growth response. The two forests have distinct structures due to differing past silvicultural management. The Camaldoli Forest, containing one-storeyed, evenaged, pure silver fir stands, was essentially managed in the past for wood production and featured high plantation density, low to moderate thinning, and clear cutting every 80–100 years. The La Verna Forest includes multi-layered, unevenaged stands that are mixed in with beech and other broadleaves. Increment cores were collected from aged dominant and healthy trees in the two forests. Climatic data were taken from the Camaldoli station and covers the period 1885–1994. All the analysed dendroecological parameters displayed similar patterns and indicated suitable site conditions for the silver fir. Silvicultural systems played an important role in defining growth pattern and rate. In the evenaged system there were higher growth rates and a greater number of pointer years, whereas there were lower growth rates and long, homogeneous development stages in the semi-natural conditions of La Verna. A rising growth trend recorded in the last three decades in both series could be explained by the consistent extension of the growing season due to a significant increase of mean spring and autumn temperatures. No correlation was found with precipitation while significant correlations were found between tree ring growth and February, April and August temperatures. Preliminary results indicated that the silvicultural system does not bias, but just enhances the ability of the species to record the effects of disturbing factors.

No official and coherent data on the distribution of the European chestnut exist despite its wide range of distribution and the important economic role it has played in many countries. In 1997, in the framework of the COST action G4 “Multidisciplinary Chestnut Research”, quantitative and qualitative data on chestnut forests were collected, mostly from the National Forest Inventories, in order to provide as sound a picture as possible of this important European resource. A total of 2.25 million hectares of forest dominated by chestnut were recorded, with 1.78 million hectares (79.0 %) cultivated for wood and 0.43 million hectares (19.3 %) for fruit production. The remaining 0.04 million hectares (1.7 %) were classified as irregular structures or without any indication. A further 0.31 million hectares are thought to be mixed forest with chestnut. Three types of chestnut countries can be distinguished : (i) countries with a strong chestnut tradition (e.g. Italy, France, southern Switzerland, Spain, Portugal and Greece), where the chestnut stands are cultivated with intensive and characteristic silvicultural systems (coppices and orchards) ; (ii) countries with only a partially developed chestnut tradition due to the country’s particular geography (e.g. England) or history (e.g. Croatia, Turkey, Georgia) ; (iii) countries where the chestnut only sporadically occurs (e.g. Hungary, Bulgaria, Belgium) or has been recently introduced (e.g. Slovakia, Netherlands). A comparison of the present distribution of traditional silvicultural systems and historical data on chestnut distribution supports the hypothesis that the large-scale chestnut forest plantations are of post-Roman origin. Chestnut cultivation is now at a turning point as the changed needs of society have changed as it has moved away from a rural-based to an industrial and urban-oriented organization. The evolution of the chestnut market in recent decades confirms the potential of this resource for both traditional products and new services and goods related to organic-food and environmentally friendly products., Il n’existe aucune donnée officielle et cohérente sur la distribution du châtaignier en Europe, en dépit de sa vaste aire de répartition et de l’important rôle économique que cette espèce a joué dans de nombreux pays. En 1997, dans le cadre de l’action COST G4 “Multidisciplinary Chestnut Research”, des données quantitatives et qualitatives ont été collectées au sujet des châtaigneraies européennes, principalement à partir des inventaires forestiers nationaux. L’objectif était de fournir un état des lieux aussi précis que possible pour cette importance ressource économique. Un total de 2,25 millions d’hectares de boisements dominés par le châtaignier a été inventorié, avec 1,78 millions d’hectares (79,0 %) cultivé pour la production de bois et 0,43 million d’hectares (19,3 %) pour la production fruitière. Les 0,04 million d’hectares restants (1,7 %) ont été classés en structures irrégulières ou n’ont pas pu être classifiés. Plus de 0,31 million hectares sont classés en tant que boisements mixtes à châtiagnier. Trois types de pays peuvent être distingués du point de vue de la castanéiculture : (i) les pays dotés d’une forte tradition castanéicole (ex. Italie, France, sud de la Suisse, Espagne, Portugal et Grèce), où les châtaigneraies sont conduites en taillis ou futaies, grâce à des sylvicultures intensives et caractéristiques ; (ii) les pays où la tradition castanéicole n’est que partiellement développée en raison de contraintes écologiques (ex. Angleterre) ou historique (ex. Croatie, Turquie, Géorgie) ; (iii) les pays où la castanéiculture n’est que sporadique (ex. Hongrie, Bulgarie, Belgique) ou a été récemment introduite (ex. Slovaquie, Pays-Bas). La confrontation de la distribution actuelle des pratiques traditionnelles et des données historiques sur la répartition du châtaignier supporte l’hypothèse d’une origine post-romaine pour les peuplements de châtaignier présents sur de vastes étendus. La castanéiculure a été profondément bouleversée par les changements socio-économiques liés au passage d’une économie essentiellement rurale à une économique de type industriel. Toutefois, l’évolution du marché durant ces dernières décennies montre que le potentiel économique de cette ressource reste bien présent, à la fois pour des produits traditionnels mais aussi pour de nouveaux services et biens., Conedera Marco, Manetti Maria Chiara, Giudici Fulvio, Amorini Emilio. Distribution and economic potential of the Sweet chestnut (Castanea sativa Mill.) in Europe. In: Ecologia mediterranea, tome 30 n°2, 2004. pp. 179-193.

International audience; & Context Six Pinus pinea stands growing under the Mediter-ranean type climate in Italy along the Tyrrhenian and Sardin-ian coasts. & Aims To identify the main climatic factors driving variability in growth responses to contrasting climate conditions at local and regional scales using tree-ring analysis. & Methods Common growth patterns in tree rings were ex-plored with clustering techniques. Local and regional growth responses to climate were examined using a dendroclimatic analysis. To remove the age-dependent trend we decomposed the tree ring width data into age-bands, thereafter standardised and recombined into a single mean site chronology. & Results The main grouping of tree ring series reflected climate-driven growth patterns, with a clear separation be-tween stands from wetter and drier sites. The most interesting results were found at a seasonal scale and showed i) a shift of the main precipitation inputs from previous autumn-winter to current early-spring period, and ii) a bimodal pattern of sen-sitivity to water availability, when increasing drought conditions. & Conclusion Our findings suggest that water deficit limits P. pinea growth also during late summer months in drier sites. In view of the projected increases in the frequency and dura-tion of summer droughts in the Mediterranean basin, detecting differences in growth responses to site-specific climate patterns may allow selection of more appropriate miti-gation and conservation strategies across most of its present range.

This study was carried out in order to analyze the effect of silvicultural treatment on the structure and productivity of the chestnut stands, on the disease evolution and on the genetic structure of the species. The study considered a coppice stand aged 35 years (1994), growing on Monte Amiata (Tuscany, Italy). In the winter of 1994–1995, a low thinning of moderate intensity was applied; all suppressed shoots were removed, the intermediate class was partially reduced while the dominant storey was lightly thinned. Before, and after thinning, a description of stand structure, evaluation of number and typology of cankers caused by Cryphonectria parasitica on each tree and characterization of genotypical profile of all stumps was carried out. The structural and pathological surveys were repeated in February 1997 in order to analyze the growth trend of the stand and to verify the incidence and the evolution of disease two years after thinning. The results show that the applied silvicultural system neither reduced the genetic variability nor influenced the genotypic distribution of the stand. The removal of virulent cankers and the reduction of the individual susceptibility by the selection of the most vigorous trees has a positive effect on pathogen evolution.

This research was conducted in a 62-year-old stone pine (Pinus pinea L.) forest within the National Natural Reserve of the Roman Coast, Italy. Net under-canopy precipitation was measured between September 2004 and December 2008 in a unthinned and a thinned area of about 1 ha each. The goals were to document and compare net under-canopy rainfall (throughfall and stemflow) in thinned and unthinned stands, and evaluate how the re-growth of tree crowns following thinning influences canopy interception. Thinning was carried out during the winter of 2002 and reduced the number of trees by 56% and leaf area index (LAI) by 63%. Rainfall, throughfall, and stemflow were measured and analysed. Interception loss averaged 23% and 40% in the thinned and unthinned areas respectively, but difference decreased during larger rainfall events. Net under-canopy precipitation was always higher (P

Producing quality chestnut timber from chestnut coppices by defining silvicultural approaches sustainable from the economic, ecological and socio-environmental point of view is a promising option for the future. Enhancing local silvicultural activities may turn in an improved quality timber production, in ecological benefits, in reducing of environmental loads related to timber import, and favouring direct and indirect (e.g., tourism) forestry industry in marginal areas. In our study we monitored the response of chestnut coppice stand to different silvicultural treatments: i) no treatment (control); ii) stand silviculture consisting in early and frequent low-thinning of moderate intensity; iii) single tree oriented silviculture consisting in early selection final target trees among the best phenotypes (up to 150 individuals per ha) and isolating their crown through free thinning in order to avoid any competition with neighbouring trees. Three experimental plots (1 in Canton Ticino, Switzerland and 2 in Toscana, Italy) were selected in homogeneous and fairly productive sites. First silvicultural interventions have been planned between January 2006 and February 2009 according to the development stage of the stand in each area. First results highlight the existence of both positive and negative aspects in all the considered options. A common trait among the thinned stands is the rapid recovery of the canopy within few years. Concerning the single tree silviculture, it allows producing a significantly higher increase in diameter of the target trees. But, it is disadvantageous in terms of extracting the harvested wood from the stand and it is highly susceptible to game damages. In the future we will carry on the research trials monitoring the considered silvicultural options also in terms of the overall economic balance.