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With ongoing global warming, increasing water deficits promote physiological stress on forest ecosystems with negative impacts on tree growth, vitality, and survival. How individual tree species will react to increased drought stress is therefore a key research question to address for carbon accounting and the development of climate change mitigation strategies. Recent tree‐ring studies have shown that trees at higher latitudes will benefit from warmer temperatures, yet this is likely highly species‐dependent and less well‐known for more temperate tree species. Using a unique pan‐European tree‐ring network of 26,430 European beech (Fagus sylvatica L.) trees from 2118 sites, we applied a linear mixed‐effects modeling framework to (i) explain variation in climate‐dependent growth and (ii) project growth for the near future (2021–2050) across the entire distribution of beech. We modeled the spatial pattern of radial growth responses to annually varying climate as a function of mean climate conditions (mean annual temperature, mean annual climatic water balance, and continentality). Over the calibration period (1952–2011), the model yielded high regional explanatory power (R2 = 0.38–0.72). Considering a moderate climate change scenario (CMIP6 SSP2‐4.5), beech growth is projected to decrease in the future across most of its distribution range. In particular, projected growth decreases by 12%–18% (interquartile range) in northwestern Central Europe and by 11%–21% in the Mediterranean region. In contrast, climate‐driven growth increases are limited to around 13% of the current occurrence, where the historical mean annual temperature was below ~6°C. More specifically, the model predicts a 3%–24% growth increase in the high‐elevation clusters of the Alps and Carpathian Arc. Notably, we find little potential for future growth increases (−10 to +2%) at the poleward leading edge in southern Scandinavia. Because in this region beech growth is found to be primarily water‐limited, a northward shift in its distributional range will be constrained by water availability. [ABSTRACT FROM AUTHOR]

Featured Application: Afforestation of mixed spruce–pine stands more resistant to windfall at the upper altitudinal limit of Romanian forests. Swiss stone pine (Pinus cembra) is a feasible solution for increasing the resistance of future mixed spruce–pine stands to windfall at the upper altitudinal limit of Romanian forests. This study aims to analyze the adaptability of ten full-sib families in two different environmental conditions and their evolution in time for predicting forward selection. At a seedling age of 33, evaluations were carried out for survival rate (Sr), growth (diameter at breast height—Dbh, and trees' height), and branch traits, as well as for stem straightness. The high level of genetic variability, inheritance rate, and trait–trait correlations, registered in both trials, ensure the success of the breeding program. The Swiss stone pine shows a very good adaptation on high-sloping lands from the upper altitudinal limit of Romania's forests, with the cross-pollinated (CP) families registering a 28.5% better survival in the Rodna trial (34° slope) compared to the Păltiniș experiment (7° slope). The consanguineous families registered only an 11% Sr in Păltiniș, while in the Rodna trial, the Sr was four times higher (in both trials, consanguineous trees were dominated). The juvenile–adult correlations of growth traits were significant, indicating that early selection could be efficient. The forward selection of the best 10% of CP families for Dbh could be applied, ensuring a 9% to 15% genetic gain. [ABSTRACT FROM AUTHOR]

The research aims to investigate the qualitative parameters of 163 lots of European beech (Fagus sylvatica L.) seeds, originated from all over Romania, in the last 30 years (1994-2023). In the context of global warming, the influence of the climatic factors (temperature and precipitations) on the beechnuts was studied for the most important counties (regarding the number of tested seed lots), Brașov and Caraș-Severin. The analyses were performed in the seed testing laboratory of INCDS "Marin Drăcea" Brașov. All laboratory analyses were made in according with the international rules established by ISTA and implemented in Romania by SR 1908/2004 standard. Average values for purity (98,6%), viability (72,8%) and mass of 1000 seeds (254,2 g) were obtained for the 163 analysed lots of European beech seeds which places them in the 2nd class of quality, with 38,7% of the lots included in the top category. The highest values of seed viability were recorded in 2004, 2016 and 2012, and the leading counties were Maramureș, Prahova, Caraș-Severin and Brașov. Generally, direct and highly significant correlations were found among the main qualitative parameters of the beechnuts (Purity, viability, and M1000) as well as a multiple correlation among them. Heavier and higher purity beechnuts will own superior viability. In both analysed counties (Brașov and Caraș-Severin), the climatic factors generally had an insignificant influence on the qualitative parameters of the beechnuts harvested especially from populations located in the ecological optimum of European beech in Romania. [ABSTRACT FROM AUTHOR]

The objective of the research consisted in the analysis of the qualitative parameters of 380 lots of seeds of sycamore maple (Acer pseudoplatanus L.) originated from all over Romania, in the last 21 years (2003-2023). In the context of global warming, the influence of the main climatic factors (air temperature and atmospheric precipitations) on the qualitative parameters of the seeds of sycamore maple was studied for two leading counties regarding the tested seed lots, Caraș-Severin and Sibiu. The research was carried out in the forest seed testing laboratory of the INCDS "Marin Drăcea" Brașov Station. All laboratory analyses, carried out between 2003 and 2023, were made in according with the international rules established by ISTA and implemented in Romania by SR 1908/2004 standard. Average values for purity (94.4%), viability (72.9%) and mass of 1000 seeds (130.5 g) were obtained for the 380 analysed lots of sycamore maple seeds which places them in the 2nd class of quality, very close to the thresholds of the first class, where 40% of the lots are included. The highest values of seed viability were recorded in 2008, 2011 and 2012, and the leading counties were Mureș, Buzău and Timiș. Positive and highly significant correlations were obtained among the main qualitative traits of the seeds as well as a multiple correlation, also positive and highly significant, between purity, viability and mass of 1000 seeds. Heavier and higher purity seeds will have better viability. In both analysed counties (Sibiu and Caraș-Severin), regarding the influence of climatic factors on the seed’s quality parameters, in the year in which the highest temperature was recorded, and fell among the lowest amounts of precipitation (year 2019), a very low values for seeds viability were obtained (penultimate place, in Sibiu, and 15th out of 20, in Caraș-Severin). The obtained results indicate a possible risk of reducing the viability of the sycamore maple seeds in the future, in the context of climate warming, with negative effects on the existence of this important mixed species in the Romanian forests. [ABSTRACT FROM AUTHOR]

The objective of this article was to inform the public opinion and specialists from agriculture and forestry regarding the latest achievements of the breeders in the two fields, namely the obtaining of new varieties of potato and spruce, with climate resilience and the ability to respond to the present and future societal needs. In the last period, major changes have been observed at all levels, from climate changes to the preferences of producers and consumers, as well as production technologies. Climatic changes, due to the global warming process through the continuous increase in carbon dioxide emissions, manifest themselves significantly through long periods of drought, with damaging effects on agricultural and forestry productions. The creation of resilient varieties allows these critical periods to be overcome, simultaneously with the use of ecological and environmentally friendly technologies. Among the most recent achievements of the breeders in agriculture and forestry is the obtaining of 12 new varieties of potato and one of spruce, with adaptive plasticity. The progress of genetic breeding, through the development of nature-based solutions, which are based on the creation of new varieties, also ensures the perpetual enrichment of the genetic pool, in addition to increasing the degree of climate resilience. With a vast activity in the field, NIRDPSB Brasov and NIRDF "Marin Dracea", continue to provide results for the benefit of sustainable development and contribute to the fulfilment of EU objectives in terms of environment and climate. [ABSTRACT FROM AUTHOR]

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Copyright of Revista de Silvicultură şi Cinegetică is the property of Societatea Progresul Silvic / Forest Progress Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was to analyse the viability of two forest genetic resources (FGR), one arboretum and two comparative trials, re-establish the limits of them (including the replications and provenances limits within them), and to establish the management measures necessary for sustainable conservation of FGR, trials and arboretum, in the forests managed by Experimental Base (B.E.) Săcele (Brașov county, Romania) of National Institute for Research and Development in Forestry “Marin Drăcea” (INCDS). In the Romanian National Catalogue of FGR are includes two populations managed by B.E. Săcele, one constituted mainly for European larch (Larix decidua) and the other principally for Norway spruce (Picea abies), both with other associated species, like Silver fir (Abies alba), European beech (Fagus sylvatica) and sycamore (Acer pseudoplatanus). Also, in the B.E. Săcele is well represented the FGR group of artificial trials, where the genetic heritage of some national and European provenances of European beech, European larch, Norway spruce, Scots pine (Pinus sylvestris), black pine (Pinus nigra) and white pine (Pinus strobus) is preserved ex situ, in comparative trials and in an arboretum. In the spring of 2022, the current state of the two forest genetic resources (spruce and larch), the arboretum (spruce, Scots pine and black pine) and the two comparative trials (beech– European provenances and larch– full-sib experiment) were analysed and the necessary works for the conservation and sustainable management of these valuable gene pool have been executed/ planned. Thus, it was executed or planned the restoration of the experimental device limits, choosing the seed trees and their materialization in the field, as well as recommending the emergency extraction of felled trees, those with broken stems, as well as standing dried trees. Further research will be carried out regarding phenotypic data, phenological studies, as well as the study of wood using cores and rounds, the data being subsequently correlated with climatic data. Finally, valuable sources will be recommended for use in similar ecological conditions, both in the regions of origin, as well as in the Curvature Carpathians, the region in which they stood out. [ABSTRACT FROM AUTHOR]

The study aims to identify Norway spruce populations with narrow crown form, within each provenance regions across the Romanian Carpathians, and to evaluate the stability of the narrow-crowned spruce compared with the classical crown form under different environmental conditions. Narrow crowned Norway spruce ideotype may presents superior resistance to wind and snow breaks compared with the classical crown form of spruce (pyramidalis). The existence of pendula and columnaris trees in 25 populations was investigated and the compliance of the necessary criteria for inclusion in FGR's Catalogue was checked. The selected populations were mapped, the narrow crown trees were described and cores were collected for determination of the wood density. The narrow crown trees present favourable results for growth traits, tree slenderness, crown diameter and wood density, compared with the trees reported with normal crown form, while natural pruning was the only unfavourable trait. For wood density, narrow crowned trees were superior in all plots but only one time the differences were significant (p < 0.05). For the first time in Romania, seven populations comprising 249 narrow crowned spruce trees were selected for their inclusion in the Romanian FGR's Catalogue with the aim of in situ conservation of this ideotype. [ABSTRACT FROM AUTHOR]

The aim of our study was to analyze the stability traits between 33 Norway spruce provenances tested in five field trials across different environmental conditions, in two major variants of the Romanian Carpathians: outside of the natural distribution range (ONR) and in the natural habitat (INR). To justify the early selection, we selected 40-year-old trees and measured tree height (Th), breast height diameter, pruning height, crown diameter, tree volume, tree slenderness (Ts), pruning height ratio, and crown slenderness, which were then compared on a time series with measurements from trees at 30 and 10 years old, respectively. All provenances reacted to the changes in the environmental conditions, presenting higher Th in the warmer ONR environments, compared with the results of the mountain INR trials, with negative consequences on the stand's stability. In all trials, highly significant differences resulted between, and especially within provenances, suggesting a high potential for adaptation in the future climate change scenario. An analysis of the stability traits suggests that we must avoid ONR afforestation with Norway spruce. All the elite provenances (Marginea, Gurghiu, Comandău, and Sudrigiu), together with Câmpeni and Turda, were highlighted, both for the stability and growth traits, whereas the local provenances and the standard IUFRO provenance were ranked below the average of the trials. The age-age significant correlations and the ranking of the provenances show that no major changes occurred in the last ten years, confirming the backward selection performed at the age of 30 years. The juvenile--mature correlations were also strong but the different evolutions in time of the elite provenances eliminate the possibility of a juvenile selection. The forward selection strategy, for the best trees belonging to the six mentioned provenances, according to Ts, can be applied in the INR trials. [ABSTRACT FROM AUTHOR]

In this paper, the effect of various factors (clone, initial explant, sterilization method, and culture medium) on the in vitro multiplication of pedunculate and sessile oak species was tested. No influence of clone was found and a 44-83% survival rate was found for different types of explants, the best result being that of using mature acorns germinated in vitro. The most efficient sterilization method was: mercuric chloride 0.2 mg/l, ascorbic acid 1 mg/l, for 30 min., with or without antibiotic. The best results were obtained with GD medium complemented with 0.5 mg/l BAP and 0.1 mg/l IBA, which allowed obtaining of a high rooting percentage. The regenerated plants were transferred in vivo, in a climate controlled greenhouse. [ABSTRACT FROM AUTHOR]

The aim of this study was the analysis of the radial growth performances and the resilience to drought of 8 halfsib provenances of Norway spruce with narrow crown (pendula form) and normal crown (pyramidalis variety) from Soveja comparative trial, at the age of 23 years, by measuring and examinations of wood cores. The results showed no statistical differences between the two forms of spruce and between provenances of the same form for radial increment in 2004-2017 period. However, the pendula provenance 7-Horoaba, which is originate from the highest altitude, obtained the best growth performances, while the provenance with the lowest radial growth, 6-Bozovici (pendula), comes from lowest altitude, outside of the natural distribution range of the species. The drought from autumn of 2011 and summer of 2012, strongly affected radial growth from the 2012 vegetation season of both spruce forms. Regarding drought resilience, no significant differences was observed between the two forms of spruce; both forms presented the same result for recovery index (>1), which means that pendula and pyramidalis spruce form have a good capacity to recover after a drought event. For resilience and resistance indices, pendula form showed a slight superiority compared with the normal crown spruce. Still, for both forms, the values for these indices were less than 1, which means that spruce from Soveja has a low resilience and resistance to long drought events. [ABSTRACT FROM AUTHOR]

The objective of the research was the vegetative multiplication of the narrow-crowned Norway spruce (Picea abies f. pendula), by grafting, in order to establish a seed orchard. The purpose of cloning the narrow-crowned spruce started from the fact that, in the research carried out in previous years, its superiority was highlighted (larger dimensions, superior wood quality and better resistance to wind and snow) compared to the usual form of Norway spruce crown (pyramidal, pyramidalis variety). In two natural populations from the Apuseni mountains (Stâna de Vale and Izbuc), as well as in the comparative clonal Soveja, 20 pendula spruce trees / ramets were selected from which fresh scions were harvested. For grafting the narrow crown spruce, the following activities are necessary: preparation of rootstock seedlings, one year before grafting; selection of graft donor trees and harvesting scions; grafting; monitoring of grafted seedlings. Rootstock seedlings must have a minimum thickness of 7 mm. The optimal grafting period lasts from the time when the buds are very swollen and until the annual growth (light green) is visible. The scions must come from sexually mature plus trees, from the last year growth of branches, with welldeveloped, unharmed buds, and the thickness of the scions must be, in the grafting area, approximately equal to rootstock seedlings, but not greater. Scions harvesting must be done when the rootstock seedlings start growing, in order to avoid long-term storage of scions. The recommended grafting method for conifer seedlings is side-veneergrafting and involves the following activities: preparation of scions; choice and preparation of compatible rootstock seedlings; tight bonding of the two symbionts, using plasticized tape; covering the grafting area with wax; labelling (clone code) and separate storage on clones. Monitoring of the grafted seedlings, in the solarium and later in the nursery, involves performing all the necessary activities for their optimal development. Vegetative multiplication by grafting, using the side-veneer-grafting method, had a success rate of 48%, resulting in a number of 595 grafted seedlings related to 20 clones, enough to set up a seed orchard on an area of about 1.5 ha. [ABSTRACT FROM AUTHOR]

The importance of increasing the adaptability of deconstructed forests to climate change scenarios and preserving forest vegetation in the forest steppe zone of Romania requires the promotion of thermophilic and xerophytic species. Of these, pubescent oak (Quercus pubescens) is one of the most suitable species for combating desertification. The necessity to have seeds with superior genetic characteristics, derived from trees adapted to the environmental conditions of the Romanian forest steppe, outlines the general objective of research represented by establishing the first clonal seed orchard for pubescent oak in Romania. The present paper describes the preliminary activities undertaken for the establishment of the seed orchard, starting with the selection of valuable populations, continuing with the identification of plus trees donors of grafted branches, the cuttings actions necessary to stimulate shoots in their crowns and ending with the first action of graft branches sampling. In the forest-steppe area of Bărăgan and Dobrogea (region of south-eastern Romania), 30 plus trees were selected, which will provide grafted branches. They are vigorous, have higher than average growth traits (Dbh, trees’ height), vertical stems, straight, cylindrical, and well developed globular crowns. In order to obtain vigorous grafts, the plus trees were covered with cuttings to stimulate sprouting in the crowns (three stages of intensity: weak, moderate, strong), works carried out one year before the sampling of the graft branches. The production of viable grafts has been closely correlated with the increasing intensity of stimulation cuttings. The sampling of graft branches complied with the condition of being carried out in a period with positive air temperatures, at least 48 hours before the collecting time. [ABSTRACT FROM AUTHOR]

The selection of narrow crown spruce phenotypes is of great interest to the Romania forestry sector, facing an increased frequency of windfalls in pure Norway spruce stands. Molecular markers are reliable screening tool for highlighting populations specific genetic characteristics. In the present investigation we used 12 nSSR markers to analyze two spruce metapopulations (Stâna de Vale and Păltiniș), where the two forms of narrow-crowned spruce (Picea abies var. pendula) and common spruce (Picea abies var. pyramidalis) are present. We observed very close values for several alleles in both metapopulations, but the separate analysis of ideotypes detected a higher number of alleles in the narrow-crowned ideotype (Picea abies var. pendula) (132 alleles) in metapopulation Stâna de Vale. The results showed higher mean of observed heterozygosity (HO) and expected heterozygosity (HE) in the Păltiniș metapopulation (HO = 0.713 and HE = 0.751), compared to the Stâna de Vale metapopulation (HO = 0.66 and HE = 0.715). The inbreeding coefficients were positive and not significantly different from zero in most cases. Genetic differentiation among populations was low (FST = 0.01182). The Bayesian clustering method highlighted a higher admixture in population Stâna de Vale, compared to Păltiniș where sub-clustering was observed between narrow and common spruce samples. The Arlequin outlier analyses conducted using a hierarchical model revealed the EATC2G05 locus, as a candidate locus (p = 0.0083). The BlastX analysis of EATC2G05 locus revealed high genetic similarity to the transposable element (MA_163458.g5035.t1) from the spruce genome. [ABSTRACT FROM AUTHOR]

In this study ten Hungarian oak provenances from Southern Romania were tested in two comparative trials 10 years after planting. The diameter at breast height (dbh) and tree height (Th) were measured in family progenies and the survival rate was determined. In both trials, the local provenances (Bals and Seaca 2) revealed superior fitness in terms of growth and adaptability traits, confirming the recommendation of using local provenances with priority in afforestation activities. Based on the measured traits, families which ranked in the first ten positions at age 3 and age 10 years were identified in both trials. The analysis of variance revealed statistically significant differences in growth traits between provenances and families in both comparative trials. Duncan's test for 5% transgression probability revealed different results for dbh and Th in terms of provenance homogeneity in the two test sites, with a superior homogeneity in the Aramadia trial for dbh and in the Bals trial for Th. Growth performances of the Hungarian oak provenances were significantly influenced by the experimental location and by the interactions between provenance, family and locality, suggesting that maximum precaution must be taken in the choice of forest reproductive materials to be planted in different environmental conditions. The family mean heritability (h2 f) was significantly lower than the individual heritability (h2 i), suggesting the possible adoption of an individual selection strategy in the next stage of the current breeding programme. The juvenile-adult correlations will be made at the age of 40 years and will take advantage of the results of this study to shorten the testing period for the selection of genetically improved material in Hungarian oak. [ABSTRACT FROM AUTHOR]

The objective of the present research consisted in the comparative analysis of the growth performances, stability and survival rate for the open-pollinated families and the hybrids obtained by controlled pollination (in a complete diallel and factorial diallel mating design) of Norway spruce trees with narrow crown (pendula form) and pyramidal crown (pyramidalis variety, the classic form), in the Comandău experiment, at age of 24 years. The results obtained by consanguineous and heterozygotes were compared with the average values of the form/ variety from which they derived. The results were compared with the previous one, registered at age of 10 year. Hybrids that relate integrally (P x P) or only maternal (P x N) to the narrow-crown spruce (pendula) have higher stability than the common spruce (pyramidalis), by: smaller crown diameters, fewer number of branches in the whorl and also thinner branches, which reduces the amount of snow in the crown canopy, avoiding the breaks caused by wind and snow. The pendula and pyramidalis consanguineous recorded average values lower with 24 - 34% for the breast height diameter and trees height, compared to the trial average, while the survival rate was lower than the average with 51% for the pendula and with 83% for the pyramidalis trees. Slightly more than half of the families and hybrids noted at the age of 10 years remain at the top of the rankings made at age of 24 years, both for the diameter at breast height and for the trees height, which indicates the possibility of early selection. This fact was also confirmed by the positive and very significant values of the age-to-age correlations. [ABSTRACT FROM AUTHOR]

The genetic inheritance of a tree species is fully expressed in the phenotype only when its ecological requirements are accomplished. Therefore, genetic tests provide the opportunity to simulate the change in the environment and determine the most suitable site conditions for specific populations. In light of the unpredictable climate conditions resulting from rapid environmental changes, the current study investigated possible signs of adaptation and productivity of European beech in the Romanian Carpathian region. For this purpose, the tree growth and stability performances, as well as the transfer effect, were examined in 17 international beech provenances tested in two different environments for 27 years. Growth and stability performances were evaluated using tree height (Th), breast height diameter (DBH), and survival (S). In the case of the transfer analyses, the ecodistance approach was applied. According to the results, the average of S was 13% higher in the Carbunari provenance trial, and DBH was higher in the Sacele trial by 15%, while no noticeable differences were registered for Th. The best-performing provenances were those originating from similar site conditions to the Romanian test sites, and the transfer function detected the sensitivity of beech provenances to increasing temperature. The general transfer response of provenances revealed a similar performance across sites and suggested that provenances exhibited adaptation and acclimation to the test environments from Romanian Carpathians. [ABSTRACT FROM AUTHOR]

The study begins with a complete analysis of the entire Norway spruce stands (36.183) from the Southern Carpathians. The main characteristics of these stands were analyzed, followed by a classification of their characteristics on favorability classes (from 1 to 5, from the lowest to the highest) based on their framing within the smart forest category. This classification has taken into account both the stand growing characteristics (diameter, height, volume, current growth), as well as some stand qualitative traits (lopping, vitality), forest functions (production/protection subunit, functional group and category) or site characteristics (flora, soil, forest type, station type). This is the first time when stands were classified based on their general adaptability character towards environment conditions, quantifying the notion of smart forests. The most representative Norway spruce smart forests are spread out in Retezat, Ierului, ureanu and Piatra Craiului Mountains, at altitudes between 1000-1300 meters, on shaded expositions, dystric cambisol soils, in stands aged between 90 and 150 years. The participation percentage of Norway spruce in the stand composition and the field's inclination does not influence the apparition of spruce smart forests. The usage of the term "smart forest" and the classification of stands in this category is a scientific and practical activity for the future. [ABSTRACT FROM AUTHOR]

The objective of the present research consisted in the comparative analysis of the growth performances and the survival rate for the hybrids obtained by controlled pollination, in a complete dialel and factorial dialel mating design, of Norway spruce trees with narrow crown (pendula form) and pyramidal crown (pyramidalis variety, the classic form), in the Lepsa - Valea Marului experiment, at 23 years after plantation time. The results obtained by consanguineous and heterozygotes were compared with the average values of the form / variety from which they derived. Hybrids that relate integrally (P x P) or only maternal (P x N) to the narrow-crown spruce (pendula) have higher stability than the common spruce (pyramidalis), by: larger diameters but smaller heights, which ensures lower slenderness index; fewer number of branches in the whorl and they are thinner (relative to the trunk diameter), which reduces the amount of snow in the crown canopy, avoiding the breaks caused by snow. The hybrids obtained from the pendula parents recorded positive heterozygosity for the breast height diameter, which recommends the use of this trait in the selection strategy. The pendula and pyramidalis consanguineous recorded average values lower with 32-39% for the breast height diameter and trees height, compared to the trial average, while the survival rate was lower than the average with 24% for the pendula and with 13 % for the pyramidalis trees. [ABSTRACT FROM AUTHOR]

The objective of the present research consisted in the comparative analysis of the resistance of the common (pyramidalis variety) and narrow crown (pendula form) spruce, on the standing trees, using the resistograph. The field works were carried out within the population Coșna, administered by forest district Dorna Candrenilor and located in the production unit III Coșna, plots 388A, B, which occupies an area of 20.5 ha. Within the stand, 40 Norway spruce trees with narrow crown were identified, 20 of them being materialized in the field. The 10 narrow-crown spruce trees chosen for testing drilling resistance belong to the pendula form, cover the population surface relatively uniform and relate to several categories of diameters. From the category of normal crown, spruce trees were also chosen 10 trees from the vicinity of the pendula trees, with similar diameters. Testing of the torsion resistance was performed at a height of 1.30 m, using the IML RESI F500-S resistograph. Analysis of the standing trees wood resistance indicates the superiority of the narrow crown spruce trees, the average amplitude indicated by the resistograph being 5.2% higher compared to the normal form, a statistically significant difference (p = 0.014). The upper strength of the narrow-crown spruce was also recorded on 5 cm fragments (except of the first fragment, nearest to the bark). This fact, in conjunction with other recent investigations, allows us to recommend the promotion of this form of Norway spruce in the afforestation works. [ABSTRACT FROM AUTHOR]

The study consisted of the evaluation of the phenology of bud burst and flowering in two oak species seed orchards, one of Pedunculate oak and one of interspecific hybridization between Q. robur and Q. pedunculiflora in order to identify the overlapping of the clones into the anthesys. An overlap of clone and ramets would involve a polycross pair with beneficial effects on the level of genetic diversity, and the phenological differences between them would have opposite effects, including possible consangvinization due to simultaneous maturation of the ramets of the same clones. The analysis of phenology has highlighted the fact that overlapping of the anthesys phenophases occurs when the clones come from the same region of origin and has only partial overlap when they have different origins, which confirms the importance of using forest reproductive material only within the same provenance region, resulting in the necessity of the phenological evaluation of the graft donor trees before their cloning. [ABSTRACT FROM AUTHOR]

In this paper is presents the current situation, evolution of the last years and the steps to follow for appropriate thinning of three Norway spruce [Picea abies (L.) Karst] field trials. The analyzed trials are located both outside the spruce's natural range, at low altitudes, and in the ecological optimum of the species, in different regions of provenance from the Romanian Carpathians and in a wide range of habitat conditions. Two of the trials are 38 years of age and the third is younger, being installed in 1996. In the two trials approaching the age at which they complete the experimental test role and are to be transformed into seed sources (Avrig and Breţcu) the trees from each population were inventoried and the necessary measurements were made to determine the slenderness index (h/dbh). The result was a very pronounced instability in trial located outside of the natural distribution range of Norway spruce, at low altitudes (Avrig trial), opposite to the one recorded in the optimum distribution range of species (Breţcu trial). In the Avrig trial, the trees slenderness index recorded the value of 109 (7% higher than the 2010 value), 27% higher than the one recorded in the optimum distribution range of the species (Breţcu), where the trees slenderness index is practically the same (has increased from 85 to 86 in the last 8 years). In Romania (Barbu 2004), as a stability limit for spruce forests, the value of the slenderness index of 100 is established; beyond this value the stands have a very high vulnerability to the wind action. In a younger comparative trial (Comandău, 22 years old), the works began by artificially pruning of the trunks of all trees, up to a height of 2 m (were cut the branches already dried). It continued with the re-labelling of the trees included in the experiment, after which the traits required to determine the slenderness index (tree height and diameter at breast height) were measured. Finally, it began the operations necessary to reduce the number of stems to 251 trees that have 2-3 stems. The average slenderness index of the 760 trees is 86, which ensures a medium - high stability of the stand. In the following years, the Comandău comparative trial will perform as experimental test. Comparative trials of provenances must be permanently monitored for the purpose of timely implementation of all the work necessary to ensure easy access to them (by artificial pruning), easy identification of trial limits, replications and populations limits, extra stems extraction, cutting of the dry trees and those who have broken peaks and are dominated. Since the tinning works are not carried out on time in Romania, it is recommended to install the Norway spruce comparative trials on rarer plants design (3 x 3 m, up to 4 x 4 m), which would also reduce the competition between trees, the genetic component having a more significant influence. It is necessary to take all necessary measures to protect these trials: inclusion in the forest management planes in a protected functional category (5G), and from the start of the fructification, also to be included in the seed sources category. At the level of each provenance, the most vigorous trees will be designated as seed trees, and among them, those which belong to the most valuable populations will be declared elite trees, having priority to reproduction. [ABSTRACT FROM AUTHOR]

The objective of the research was to identify an optimal method for grayish oak (Quercus pedunculiflora) in vitro multiplication. The working hypotheses of the research aimed to: »» identify the type of explants and the most efficient methods for sterilization; »» establishing the optimal hormonal balances; »» determination of suitable culture medium for in vitro multiplication and rooting of greyish oak; »» establishing an in vitro micropropagation protocol: multiplication, rooting and in vivo transfer. Several types of plant materials were tested for in vitro culture initiation: nodal segments of in vivo germinated acorns and, immature and mature, in vitro germinated acorns. The explants were maintained on the culture medium for 4-6 weeks, until the first leaves appeared. Cultures were carried out at a temperature of 25°C±1°C, relative humidity of 70% and a photoperiod of 8 hours light and 16 hours darkness throughout the experiments. For initiation of in vitro cultures for grayish oak, the type of plant material most desirable was represented by mature acorns, germinated in vitro. The sterilization method significantly influences the survival of the explants. The most indicated culture medium (GD2 type supplemented with 0,5 mg/l BAP) allows a good rooting. The researches have set the stage for the use of in vitro cultures for the ex situ conservation of forest genetic resources of grayish oak, germ plasma conservation by tissue culture, constituting an alternative method for the preservation of genetic diversity. [ABSTRACT FROM AUTHOR]

With the purpose of establishing a seed orchard of gray oak (Quercus pedunculiflora) which will provide acorns for the whole area of the Dobrogea forest steppe (region of south-eastern Romania), in this paper are presented the most important aspects of obtaining grafted plants stage, whose accomplishment involves carrying out the following steps: » choosing trees donors of grafts, stage which was previously discussed (Budeanu et al. 2014), » performing cuttings for stimulating growth of annual branches in tree crowns of grafts donors, » sampling of graft branches, » vegetative multiplication by grafting, » monitoring of grafted plants. Another working hypothesis which will be discussed in this material is represented by performing of phenological observations regarding flowering period of tree graft donors, which will allow, for the first time in Romania, the arrangement of grafted plants in the future seeds orchard to be carried out in strong correlation with flowering period of the clones: the clones with flowering in the same period will be placed beside. To obtain viable graft branches one year before sampling branches are necessary to performed moderate - high intensity interventions in the crowns of grafts donors. Between the interventions intensity and the number of graft branches sampled were resulted a positive and very significant correlation. Gray oak vegetative multiplication, in a controlled atmosphere, through improved copulation method, it was resulted in a 31.5% rate of success of grafting at the end of the first growing season. In the Murfatlar seed orchard were identified donor clones of gray oak var. atrichoclados that are flowering in the same period, thus will be assured the genetic gain in the 2nd seed orchard generation. [ABSTRACT FROM AUTHOR]