Abstract: Ensuring sustainable forestry in a changing environment requires implementing effective methods for selecting seedling material with enhanced tolerance to adverse abiotic and biotic factors. Previous strategies often relied on time−consuming field tests or costly molecular analyses. In the present study, we present an analysis of cotyledon number as a morphological trait allowing rapid prediction of potential stress resilience in Scots pine Pinus sylvestris seedlings. Assessment of this parameter may serve as an easily observable phenotypic marker enabling early identification of individuals with more favourable morphological development and enhanced adaptive potential. The quality of the seeds used was assessed according to the first category of quality indicators. The average number of cotyledons in seedlings, both in the laboratory and in the nursery, was slightly above 6 (p<0.05). Statistically significant differences were found in the measured parame− ters of seedlings with different numbers of cotyledons (p<0.0001). The percentage of seedlings grown in the nursery with values within the optimal ratio (R:S=1.0−1.5) was 94%. The study was based on the analysis of cotyledon number distribution and its relationship with selected biometric traits of seedlings obtained under laboratory and nursery, conditions. We demonstrated that increased cotyledon number correlates with increased root, shoot, and needle length, as well as higher survival potential. The observed correlations indicate that cotyledon number may serve as a rapid and costeffective selection criterion in forest practice and breeding programs, offering a useful alternative to more advanced technologies. Simultaneously, further validation of results in stress experiments and across a broad spectrum of genotypes and locations is necessary to effectively implement this method as a tool in assessment of seed and nursery stock quality.
Key words: early growth indicators, phenotypic traits, population resilience, seedling selection, stress adaptation

Abstract: Cytisus scoparius is the species native to western and central Europe. A century ago, its historical range limit extended through central and eastern Poland, and, due to the damage by heavy frosts, the species had a dwarf−shrub habit, was moderately rare, and grew mainly in forest edges. Nowadays, it is considered invasive in many parts of the world. It also extends its native range to Eastern Europe, and this process is seen as a good indicator of climate change. The study aimed to recognize the present variability and dynamics of C. scoparius formations in central Poland, which is in close vicinity to the historical range limit of the species. The research was conducted south of and southwest of Warsaw. The 11 sites of C. scoparius were repeatedly studied in 2022 and 2025. The phytosociological relevés were taken, and the mean and maximum height of brooms in vegetation plots was measured. The locations and size of broom scrub patches were delimited with GPS and orthophotomaps. The data were ordinated with selected vegetation traits as passive variables, helping to understand the vegetation changes between the two surveys. The studied formations of C. scoparius have turned out to be well−developed and vital nowadays, and the height of the brooms has not decreased. All known successional stages: the stand initiation, stem exclusion (intermediate), and senescent, were documented. The terminal stage of the formation was additionally distinguished in two sites. Some sites suffered heavy disturbance, crucial for the C. scoparius scrub’s reestablishment and thriving. The total area within the studied sites increased. Despite the decrease due to severe disturbances within some sites, it quickly spread into adjacent areas in other ones. Nowadays, the S8 expressway probably serves as a local corridor for the species. We think that the current climate does not seem to be the limiting factor for the species in the studied area, located close to its historical range limit.
Key words: Calluno−Sarothamnetum, climate change, community with Cytisus scoparius, disturbance, ecological succession, Mazovia, Sarothamnus scoparius, species expansion

Abstract: The spruce seed moth, Cydia strobilella, is the main pest in Norway spruce Picea abies seed plan− tations, causing significant losses in seed production. Effective pest management strategies require precise phenological data, particularly base temperature (Tb) and accumulated growing degree days (GDD), which are necessary to determine the onset and peak of moth flight. This study aimed to determine the Tb and GDD for the beginning and peak of C. strobilella flights in Poland. Spruce cones were collected from three forest districts (Pniewy, Nowogród, and Łomża) and placed in photoeclectors and rearing containers. Tb was determined using linear regression of development rates at five constant temperatures (6−10°C). No development was observed at 4°C or 5°C; therefore, the base temperature was estimated by extrapolating the regression line below the observed range. The GDD for the onset and peak of flights was cal− culated using the single triangle method with a horizontal cut−off, based on hourly temperature data recorded in the photoeclectors. The results showed that the Tb for C. strobilella was 5.45°C (95% CI: 4.95−5.94°C), which is lower than that of other Cydia species, reflecting its adaptation to boreal and subarctic climates. The beginning of moth flight occurred at approximately 130 GDD, while the flight peak, defined as the first day when the proportion of captured females exceeded that of males, was observed at approximately 180 GDD. These results provide key information for developing precise phenology−based pest management strategies for Norway spruce seed plantations, optimising the timing of protective measures, and minimising seed losses caused by C. strobilella.
Key words: base temperature (Tb), growing degree day (GDD), Cydia strobilella, spruce seed moth, seed plantations, Picea abies

Abstract: Despite the universal availability of cultivated fruit species, wild fruits continue to play a significant role in many regions of Europe. For centuries, forests have been the primary source of valuable food and medicinal resources, and they continue to compete successfully with agricultural production. Bilberry fruit is one of the most important non−wood forest products harvested in northern, central, and eastern Europe. It is expected that harvest will remain at a consistently high level, as bilberry fruit is one of the resources that can only be picked in the forests. This is due to the fact that the plant from which it originates is not suitable for cultivation. The nutritional benefits of the bilberry fruit are related to both exceptional flavour and high content of anthocyanins. They are known as antioxidant substances useful in the dietary prevention of cancer, cardiovascular disease, neurodegenerative disorders and ageing. In Poland, bilberry fruit is not only picked for personal use, but also harvested in large quantities for both informal roadside trade and processing in the food industry. This study aimed to determine the optimal harvest period and identify the forest site type suitable for bilberry industrial−scale harvesting. Bilberry fruits were harvested from June 9^th to August 18^th, 2025, within the Leżajsk Forest District from two forest site types: fresh coniferous forest and fresh mixed coniferous forest. Along 150−meter transects, 150 g of randomly selected, ripe fruit were picked at three−day intervals. The following measurements of physical parameters were performed: colour (CIE L*a*b* colour scales), refractive index (expressed as Brix), and percentage of dry matter content. The study showed that both refractive index and dry matter content differed significantly depending on the forest site types; in both cases, higher values were observed for the fresh coniferous forest. On the other hand, L*a*b* measurement has identified a period when bilberry fruit is characterised by stable colour. Based on all the results obtained, the study identified the most favourable forest site type and the optimal period for harvesting raw materials of the highest quality and economic profitability in a food industry.
Key words: food industry, forest fruits, harvest period, non−wood forest products, quality requirements

Abstract: This article presents a critical case study analysing the impact of halting timber harvesting in Germany’s public old beech forests, Fagus sylvatica, (170,000 ha, aged 140−160 years, timber stock 425−444 m³/ha, beech >75%) on carbon balance and climate mitigation. The segregation policy – separating protection from production – assumes these stands act as stable CO₂ reservoirs, yet forest inventory data and literature reveal underestimation of risks from drought−induced mortality, pests, pathogens, windthrow, and natural deadwood decomposition that could transform forests into net carbon sources within decades. The methodology combines systematic literature synthesis on temperate beech carbon dynamics (sequestration rates, decay timescales, harvesting emissions, soil fluxes, product lifecycles), quantitative analysis of German and Polish national forest inventories (timber stocks, age structures, assortments), and comparative policy evaluation. Both nations manage ecologically similar beech ecosystems (F. sylvatica dominant, 7−9°C temperatures, 600−850 mm precipitation, Cambisols/ Luvisols), contrasting Germany’s non−intervention with Poland’s active management. Beech wood (density 680−720 kg/m³, diffuse−porous, machinable for peeling/bending) substitutes high−emission materials: 1 m³ sequesters 1281 kg CO₂ while displacing concrete, steel, plastics. In 2024 Poland’s Regional Directorate of State Forests in Kraków harvested 100,000 m³ from thinnings: 43% large assortments (furniture, flooring, sleepers), 44% pulpwood (particleboard, viscose, paper), 13% energy wood extending carbon storage via cascading use, especially furniture industry. Passive protection projects theoretical stock growth to 575−736 m³/ha by 2050 (1.9 Mt CO₂/year uptake), but primeval references show decay phases reducing volumes 40−70% over 50−70 years; temperate deadwood releases 60−70% carbon in 10 years. For 170,000 ha, this forecasts ~60 Mt CO₂ emissions (2050−2075), excluding soil losses. Harvesting emissions (15−25 L diesel/m³, ~5400 t CO₂/100,000 m³) plus temporary soil declines (5−15%, recovering 20−30 years) remain lower; unmanaged stands face equivalent disturbances without regeneration boost. Domestic harvest cessation triggers ‘leakage’ – exploitation shifts to lower−standard regions−increasing global emissions. oland demonstrates integrative viability: 0.66 million ha beech (7.1% cover), mean age 61 years, rotation 100−120 years, 2023 increment 63.2 million m³ exceeding 40 million m³ harvest by 36%. Regulated thinnings sustain high growth phases, FSC−certified biodiversity (protected zones, riparian buffers), and substitution benefits while matching German stocks landscape−wide. Climate Smart Forestry (CSF) proves superior, integrating silviculture, substitution, fossil displacement, and avoiding leakage to meet EU durable reservoir standards. Harvest suspension risks greenwashing biogenic stocks as fossil offsets; Poland’s model offers empirical Central European alternative aligning forestry with genuine climate goals.
Key words: Climate Smart−Forestry (CSF), forest carbon balance, material substitution with wood, Sustainable forest management, timber harvesting suspension and CO₂ emissions

Abstract: The stability of slopes and ditch bottoms, as elements of the road, is an important factor in keeping the road drainage system operational. This paper presents the practical application of close−range photogrammetry, GIS analysis on rasters, and geotechnical studies to determine the stability of a sample roadside ditch slope over a three−year period from 2019. The studied object is located in the Limanowa Forest District (Poland, Kostrza Forestry, section 22a), and consists modernized road (in 2019) with open roadside ditches. The formation of natural landslides of the originally very steep slope and deformation of the ditch grade line, including a landslide of the slope, was found. The observed internal friction angles in the soils of the landslide slope are very close to the average values in similar soils. The soil slid into the ditch and raised its bottom by more than 0.60 meters in places, resulting in the loss of patency of the ditch and severely limiting the functioning of this element of road drainage. However, part of the slope remained in its original, very high gradients and did not change its geometry.
Key words: close−range photogrammetry, escarpment plane stability, excavation escarpment, landslide, low altitude drone flight