In regenerated oak forests, weeds are present throughout the year, the ones appearing in early spring representing a major problem. Hence, the aim of this study was to examine herbicides for early spring broadleaved weed control in the regenerated oak forests while the seedlings are in a dormant stage. During 2019 and 2020 two experiments were set up in regenerated pedunculate oak forests with 2-yar and 3-year-old seedlings and two herbicides were applied in two doses: fluroxypyr at dose 360 g a.i. ha-1 and 540 g a.i. ha-1 and clopyralid at dose 100 g a.i. ha-1 and 120 g a.i. ha-1. The results from the two-year investigations showed that fluroxypyr and clopyralid significantly reduced early spring broadleaved weeds in the regenerated pedunculate oak forests but both doses of fluroxypyr provided greater control of presented weeds than the applied doses of clopyralid. The manual weeding reduced broadleaved weeds in experiments, but that method did not have a long-term effect on the reduction of weeds. Applied doses of herbicides fluroxypyr and clopyralid did not cause phytotoxicity symptoms in dormant oak seedlings. All investigated treatments significantly reduced fresh broadleaved weed biomass compared to the control. Generally, it can be concluded that fluroxypyr and clopyralid can be successfully used for control of many early spring broadleaved weeds in the regenerated pedunculate oak forests, but oak seedlings must be in the dormant stage.

(1) We document the invertebrate fauna collected from 24 oak canopies in east and west Norway as a contribution to the Norwegian Biodiversity Information Centre’s “The Norwegian Taxonomy Initiative”. (2) A snap-shot inventory of the canopies was recorded by means of emitting a mist of synthetic pyrethroid into the canopies at night using a petrol-driven fogger, collecting the specimens in butterfly nets spread on the ground under the canopy. (3) Almost the entire catch of more than 6800 specimens was identified to 722 species. Out of 92 species new to the Norwegian fauna, 21 were new to science and additionally 15 were new to the Nordic fauna. Diptera alone constituted nearly half of the species represented with 61 new records (18 new species). Additionally, 24 Hymenoptera (one new species), six oribatid mites (two new species) and one Thysanoptera were new to the Norwegian fauna. (4) Our study emphasis the importance of oak tree as habitat both for a specific fauna and occasional visitors and it demonstrates that the canopy fogging technique is an efficient way to find the ‘hidden fauna’ of Norwegian forests. The low number of red listed species found reflects how poor the Norwegian insect fauna is still studied. Moreover, the implication of the IUCN red list criteria for new described or newly observed species is discussed.

This study assessed the periodic fluctuations among microbial biomass Carbon (C), Nitrogen (N) and Phosphorus (P), and the consequences of variations in altitude and abiotic factors on the soil microbial biomass (C, N and P) in a temperate mixed-oak pine forest of Central Himalaya. This research was directed at three forest stands along an altitudinal gradient. Samples were collected in triplicates, seasonally from each selected site and microbial C, N and P were determined through the fumigation extraction method. Microbial biomass C, N and P decreased significantly (P<0.01, correlation coefficient -0.985, -0.963, -0.948, respectively) with increasing altitude, while the rainy season showed the highest values, and winter season revealed the least values. Microbial biomass C, N and P showed positive correlation with silt particles, water holding capacity, bulk density, porosity, soil moisture, organic C, total N and P, and negative correlations with sand particles and soil pH. The microbial biomass C showed strong associations with soil microbial N (r=0.80, P<0.01) and P (r=0.89, P<0.01) contents, while the soil microbial biomass N and P also showed strong positive correlation (r=0.92, P< 0.01). Soil microbial biomass was greatly influenced by the altitude and abiotic variables whereas, weakly by temporal variation. The microbial C: N ratio indicated that fertility of soil is influenced by the species assemblage. Our findings suggest that high microbial biomass and low C: N ratio during rainy season could be considered as a strategy to conserve nutrients by temperate mixed-oak pine forest ecosystem.

There is a restricted knowledge about the potential impact of the use of different wood species on color and anthocyanin changes during the red wine aging process. This lack of knowledge is even greater when no oak wood species are used. Thus, the aim of this study was to carry out a comparative analysis of the impact of wood chip extracts from oak, acacia and cherry species on the chromatic characteristics and anthocyanins changes by the use of model wine solutions. In this context, several methodologies were used to quantified, color and anthocyanins changes during the aging time studied. The results indicated that the contact between wood chip extracts and grape skin isolated anthocyanin extracts induced a decrease of color intensity, particularly red color, and also the anthocyanin content in the different experimental model wine solutions studied. All chromatic modifications are potentially detected by human eyes because ΔE values were much higher than 3 CIELab units. These tendencies seems to be independent of the wood species used, but more pronounced for higher contact time between wood chip extracts and anthocyanins. The obtained results may contribute to a better understanding of the chromatic changes of red wines when aged in contact with different wood chips species.

White oak mortality is a significant concern in forest ecosystems due to its impact on biodiversity and ecosystem functions. Understanding the factors influencing white oak mortality, particularly the soil properties, is crucial for effective forest management and conservation efforts. In this study, we aimed to investigate the spatial pattern of white oak mortality and examine the influence of soil properties on mortality rates. Multicycle Forest Inventory and Analysis data were compiled to capture white oak plots across the eastern US. White oak mortality data were collected across plot systems that utilized Diameter at Breast Height between two periods. Soil variables were analyzed to assess soil properties. Spatial analysis techniques, including geostatistics and regression modeling, were used to analyze the relationship between white oak mortality and soil characteristics. Results found clustered spatial patterns of white oak mortality across a broad scale depicting the significant effects of coarser soil textures, nutrient-deficient sites, and extreme soil moisture levels. Our findings demonstrated the importance of soil properties in shaping the spatial pattern of the white oak mortality rate. This idea can inform forest management practices for the conservation of white oak populations. Future research is needed for comprehensive soil assessment including biotic and abiotic factors for forest management strategies at a broader scale aimed at mitigating white oak mortality.

White oak mortality is a significant concern in forest ecosystems due to its impact on biodiversity and ecosystem functions. Understanding the factors influencing white oak mortality, particularly the soil properties, is crucial for effective forest management and conservation efforts. In this study, we aimed to investigate the spatial pattern of white oak mortality and examine the influence of soil properties on mortality rates. Multicycle Forest Inventory and Analysis data were compiled to capture all white oaks across the eastern US. White oak tree mortality data were collected across plot systems that utilized Diameter at Breast Height between two periods. Soil variables were analyzed to assess soil properties. Spatial analysis techniques, including geostatistics and regression modeling, were used to analyze the relationship between white oak mortality and soil characteristics. Results found clustered spatial patterns of white oak mortality across a broad scale depicting the significant effects of coarser soil textures (p = 0.00), nutrient-deficient sites, and extreme soil moisture levels (p <0.1). Our findings demonstrated the importance of soil properties in shaping the spatial pattern of white oak mortality rate. This idea can inform forest management practices for the conservation of white oak populations. Future research is needed for comprehensive soil assessment including biotic and abiotic factors for forest management strategies at a broader scale aimed at mitigating white oak mortality.

This scientific paper examines the impact of climate change on the spread and survival of the invasive species Corythucha arcuata (Oak Lace Bug, or OLB) in Romania. The OLB is native to the Eastern USA and Canada, and in its native habitat, it coexists with minimal impact to the preferred host plant species Quercus. However, in Europe, the OLB in high-density causes early defoliation, slowing tree growth and it leads to the death of trees. As Quercus is a keystone species, the impact of the OLB on European forests is significant. This paper aims to address several gaps in knowledge about the OLB by presenting findings from a study conducted by the Lucian Blaga University of Sibiu (ULBS) in Romania. The study identified the species ‘chronology of spread, ecology, ethology, and biology of the species, in addition to foliage classification to determine the extent of attack. The study found a direct link between temperature and speed of the generational lifecycle. The findings support the thesis that climate change is enabling the healthy, rapid density growth of OLB, which is a danger to the Quercus sp. Further research is needed in the area of the thermal tolerance of the OLB, and the research conducted by the ULBS represents the first documented research into the thermal constant of the insect. The paper concludes that further research must be in the direction to understand how and where these insects survive during winter to find future management measures and identify chemical or biological methods as solutions to eradicate and stop the expansion of the invasion of the OLB, and the potential consequences for the Quercus sp.

In Portugal, cork oak (Quercus suber L.) stands cover 737 Mha, being the most predominant species of the montado agroforestry system, contributing for the economic, social and environmental development of the country. Cork oak decline is a known problem since the late years of the 19th century that has recently worsen. The causes of oak decline seem to be a result of slow and cumulative processes, although the role of each environmental factor is not yet established. The availability of Sentinel-2 high spatial and temporal resolution dense time series enables gradual processes monitoring. These processes can be monitored using spectral vegetation indices (VI) once their temporal dynamics are expected to be related with green biomass and photosynthetic efficiency. The Normalized Difference Vegetation Index (NDVI) is sensitive to structural canopy changes, however it tends to saturate at moderate-to-dense canopies. Modified VI have been proposed to incorporate the reflectance in the red-edge spectral region, which is highly sensitive to chlorophyll content while largely unaffected by structural properties. In this research, in-situ data on the location and vitality status of cork oak trees are used to assess the correlation between chlorophyll indices (CI) and NDVI time series trends and cork oak vitality at the tree level. Preliminary results seem to be promising since differences between healthy and unhealthy (diseased/dead) trees were observed.

Ageing wine is a commonly practice used in winemaking since the quality and sensory profile increase due to the extractable compounds coming from wood by means of barrels or chips. The quantitative and qualitative compounds from wood depend on the species, its origins and the treatments applied in cooperages. Traditionally, oak wood species are most often used in cooperage, specifically Quercus alba, Known as American oak and Q. robur and Q. petraea both known as French oak. However, although this stage is very common for red wines, its use is still restricted in the case of white wines. However, this topic is particularly interesting, since due to the sensorial benefits of wood contact, the option for ageing white wines in barrels or chips is increasingly and widely chosen by winemakers. This review compiles the novel strategies applied to white wines by means of wood contact in the last years with the aim to increase wine quality and sensorial features.

Little is known about how the degree of mixing of forest-forming species affects forest floor hydrology. We evaluated the water storage capacity of the resulting litter layer by mixing litterfall of Scots pine and sessile oak and studying their decomposition time. We prepared 90 artificial samples containing pure pine litter, pure oak litter, and mixed pine-oak litter with varying shares of pine needles. These samples were subjected to 15 months of decomposition in soil. After every three months of decay, some samples were removed from the soil, and their water storage capacity, bulk density, and C:N ratio were evaluated. Our findings indicate that samples with the greatest water storage capacity had a low C:N ratio and a predominant share of oak leaves. Conversely, samples with a high C:N ratio and a predominant share of pine needles had the lowest water storage capacity. After 12 and 15 months of decomposition, the water storage capacity increased by more than 52% compared to the initial water capacity of the samples. The highest increase in water storage capacity (>40%) was observed in samples with a predominant share of oak leaves, while the lowest (approximately 28%) was recorded in samples with 80 and 100% of pine needles.

Background: As long-lived organisms, urban trees often encounter development and redevelopment activities in close proximity during their lifespans. These activities can damage tree roots, often through methods like root severing during trenching or excavation. Methods: In 2017, we simulated trenching damage on mature Quercus virginiana Mill. trees at three different distances from the base (3x, 6x, and 12x the stem diameter). After five years, we revisited these trees to assess root regrowth based on the cut root's cross-sectional area (CSA) and distance from the base. Results: We observed regrowth in all but 38 (6.7%) of the 557 cut roots revisited. The lack of regrowth in some roots was not associated with our original treatments, the CSA of the roots at the time of trenching, or distance between the cut root end and the trunk (minimum P-value = 0.841). On average, the observed CSA of the regrowth was 22.2% of the original root's CSA. Only our original trenching treatments significantly predicted the level of regrowth observed five years after pruning (P-value = 0.024). Discoloration due to root pruning was minimal. Conclusion: In summary, our findings indicate that root systems require many years to recover from trenching damage. Increasing the distance between trenching activities and trees may have a minor effect on root regrowth but primarily helps reduce initial stress on the tree.

Cork oak tree (Quercus suber L.) symbolises Montado landscape in Portugal and is a central element in the country's social and economic history. In recent decades, the loss of thousands of cork oaks has been reported, revealing the ongoing decline of these agro-forestry ecosystems. This emblematic tree of the Mediterranean Basin is host to the soil-born root pathogen Phytophthora cinnamomi, an active cork oak decline driver. In this framework, the early diagnosis of trees infected by the oomycete by non-invasive methods should contribute to the sustainable management of cork oak ecosystems and motivated this work. Using leaf reflectance spectroscopy it was possible to distinguish plants inoculated with P. cinnamomi from non-inoculated plants in a long course assay and to argue about the factors contributing to this differentiation. Spectral acquisitions in the visible-near infrared (400–1100 nm) were performed at 63, 78, 91, 126 and 248 days after inoculation (DAI), on the abaxial and adaxial faces of the leaves, and the spectral data was arranged in a three-way array of samples × wavelengths × days. The separation of the two plant groups were attributed to variations in water content (4v (O−H)) and/or a shift in the red edge and to structural modifications in the epidermal layer and/or the mesophyll of the leaves observed in the visible range. These spectral signatures can assist in the field identification of cork oaks that are interacting with P. cinnamomi.

Acute Oak Decline (AOD) is complex syndrome affecting Britain’s keystone native oak species, (Quercus robur L. and Q. petraea L. (Matt.) Liebl.), in some cases causing mortality within five years of symptom development. The most distinguishable symptom is weeping stem lesions, from which four species of bacteria have been isolated: Brenneria goodwinii, Gibbsiella quercinecans, Lonsdalea britannica and Rahnella victoriana. We do not yet know where else these bacteria exist, and little is known about the relationship of the wider oak leaf microbiome (phyllosphere) to acute oak decline. Here we investigate whether incidental evidence from a large oak genome re-sequencing dataset could be used to detect these bacteria in oak foliage, and whether bacterial incidence co-varied with AOD status or location. Oak leaves and buds were sampled from 421 trees at five sites in England. Whole genomic DNA from these samples was shot-gun sequenced with short reads. Non-oak reads were extracted from these data and queried to microbial databases. Reads uniquely matching AOD-associated bacterial genomes were found to be present on trees from all five sites and included trees with active lesions, trees with historic lesions and trees without AOD symptoms. The abundance of the AOD-associated bacteria did not differ between tree health categories but did differ among sites. We conclude that the AOD-associated bacteria may be members of the normal oak microbiome, whose presence on a tree is not sufficient to cause AOD symptoms.

(+)-epi-Epoformin (1), is a fungal cyclohexene epoxide isolated together with diplopimarane and sphaeropsidins A and C, a nor-ent-pimarane and two pimaranes, from the culture filtrates of Diplodia quercivora, a fungal pathogen for cork oak in Sardinia, Italy. Compound 1 possesses a plethora of biological activities including: antifungal, zootoxic and phytotoxic activity. The last activity and the peculiar structural feature of 1 suggested to carry out a structure activity relationship study, preparing eight key hemisynthetic derivatives and their phytotoxicity was assayed. The complete spectroscopic characterization and the activity in the etiolated wheat coleoptile bioassay of all the compounds is reported. Most of the compounds inhibited growth and some of them had comparable or higher activity than the natural product and the reference herbicide Logran. As regards the structure-activity relationship, the carbonyl proved to be essential for their activity of 1, as well as the conjugated double bond, while the epoxide could be altered with no significant loss.

Oaks are a dominant and key tree species in Mediterranean forest ecosystems. However, in recent decades, oak forests have been heavily impacted by oak decline, a worldwide phenomenon exacerbated by climate change. The charcoal disease agent Biscogniauxia mediterranea is involved in the decline of Mediterranean oak formations in a variety of contexts. Here, we investigated the impact and role of B. mediterranea in decline of oaks in Castelfidardo Forest, a relict wood of the late Holocene and a Site of Community Importance. We established five plots within which we recorded the tree positions, any symptoms and signs of decline, association of B. mediterranea to declining trees, and the deadwood and associated mycota. Of 471 oaks inspected, 7.0% showed brownish exudates on the stems, 46.9% showed epicormic shoots along the main trunk, and 24.4% showed black carbonaceous stromata on diseased branches and trunks. The decline was most severe for Quercus cerris, which comprised plots #4 and #5, at 50.0% (81/162 trees) and 29.0% (33/114), respectively; then for Quercus robur for plot #3, at 40.0% (38/95); and finally for Quercus pubescens for plots #1 and #2, at 13.7% (7/51) and 12.3% (6/49), respectively. Bark tissue was collected from trees with charcoal cankers, with microscopy examination and identification by mycological and molecular methods. This investigation revealed close association between oaks with pronounced reduction of vitality and incidence of B. mediterranea. The deadwood was equally distributed among the five plots, and was heavily colonized by Basidiomycota. The high incidence of this oak-weakening pathogen B. mediterranea appears to be related to stress conditions (e.g., water scarcity, prolonged drought). However, absence of silvicultural management, high competition among physiologically mature trees, and the geographic isolation of this residual forest might have predisposed these oaks to decline.

Our previous in vitro reports showed that crude extract prepared with 50% ethanol (ethanol crude extract, ECE) from Mongolian oak cups possessed excellent antioxidant capacities as well as inhibitory activities against α-glucosidase, α-amylase and protein glycation caused by its enrichment in phenolics, including mainly ellagic acid, kaempferol and their derivatives. Nevertheless, few in vivo studies on antidiabetic activities of these phenolics were conducted. The present study investigated hypoglycemic effects with normal and diabetic rats being administrated orally without or with ECE at 200 and 800 mg/kg for 15 days. In normal rats, no significant differences were exhibited after ECE administration in body weight, fasting blood glucose level, levels of chelesterol, triglyceride, LDL and AST in serum, organ indexes, and levels of GSH and MDA in organs. In diabetic rats, the fasting blood glucose level, indexes of heart and liver, and levels of chelesterol and triglyceride in serum and MDA in heart tissue were significantly decreased. Moreover, HDL levels in serum and SOD activities in the four organs of diabetic rats were significantly improved after ECE administration at 800 mg/kg. Thus, in addition to inhibiting α-glucosidase, α-amylase and protein glycation reported previously, oak cups might contain novel dietary phytonutrients in preventing abnormal changes in blood glucose and lipid profile and attenuating oxidant stress in vivo. The results also implied that it is ellagic acid, kaempferol and their derivatives enriched in ECE that might play vital roles in managing type 1 as well as type 2 diabetes.

The antimicrobial properties of the new strains of microorganisms isolated from natural sources of various ecological niches in the Moscow Region and the Republic of Tatarstan were studied. An antifungal activity of isolates was established in a test culture of toxin-producing microscopic fungi that cause various plant diseases: Fusarium oxysporum, Aspergillus flavus, Penicillium spp. and Candida albicans. Of the 46 studied microorganisms, 4 isolates (Bacillus subtilis, Propionibacterium freudenreichii, Lactobacillus plantarum and Streptomyces spp.) showed an ability to produce biologically active metabolites with a pronounced antimicrobial potential. This is promising in the growth and protection of the Scots pine, pedunculate oak and small-leaved linden forest crops from diseases caused by fungi Lophodermium pinastri Chev. and Microsphaera alphitoides stimulation. Based on selected isolates, a Bacterial product LRV composition has been developed. A Scots pine, pedunculate oak and small-leaved linden seedlings single and double foliar treatment with Bacterial product LRV at a concentration of 10 ml/l led to an increase in the growth of an above-ground part by 31.8, 51.9 and 25.4 %, respectively, and an underground part – by 25.0, 37.2 and 25.7 %, respectively, compared with the control. The weight of seedling at the end of the study exceeded the control variant by an average of 26.0, 44.0 and 78.0 %, respectively. A use of a plant protection Bacterial product LRV did not have a significant effect on a powdery mildew and Schütte disease damage to forest crops. A Biogeosystem Technique methodology has been developed to improve a long-term forest growing.