An analysis was undertaken of the Brinell hardness of silver birch wood and its dependence on stand location, tree age, tree thickness and forest habitat type, and the interactions between these factors. Wood was obtained from 12 forest districts throughout Poland, from trees aged approximately 30, 50, and 70 years. A total of 51 study plots was established, from which 306 trees were taken. Hardness was measured on three surfaces (transverse, radial, and tangential sections) for 4777 samples, giving a total of 14,331 measurements. It was shown that the hardness of silver birch wood in Poland is significantly influenced by location, tree age, tree thickness, and habitat type, and by interactions between those factors. Habitat type was not shown to affect radial hardness, except in the case of Giżycko forest district. For the whole of the analysed material, the mean hardness on a transverse section was calculated as 66.26 MPa, corresponding to a very hard wood on Mörath’s scale, whereas the values for the longitudinal sections (radial 44.06 MPa, tangential 44.02 MPa) correspond to a soft wood.

The collection, sale, and processing of non-wood forest products are becoming a significant factor in stimulating regional development and improving the economic situation, especially of poor rural communities. The fashion for a healthy lifestyle is also conducive to the growth of interest in such goods. Among them, birch sap is indicated as one of the most promising non-wood forest resources of central Europe, with very wide possibilities of its practical use, e.g., in the food, pharmaceutical, and cosmetics industries. The potential increase in birch sap commercial use prompts research on both the principles of its collection and the impact of various factors on its quality. In this presentation, we decided to investigate how the daily volume and selected sap parameters change depending on the location of the holes in relation to the cardinal directions. The research was conducted in April 2018, in the eastern part of Poland, in a stand with a dominant share of silver birch (Betula pendula Roth) at the age of approximately 100 years, in a fresh broadleaved forest habitat. On each of the six selected trees, four holes were drilled at a height of 1 m, positioned according to the cardinal directions (N-E-S-W). Sap was collected twice, one week apart, always after 24 h of leak. In each case, the daily volume of the obtained sap was determined, and then the selected properties of the sap were tested: electrolytic conductivity (proving, among others, the content of pro-health minerals), refractometric index (proving the approximate content of sugar), pH, and the percent of dry matter. As a result of the research, it was found that the location of boreholes in the tree trunk in relation to the cardinal directions (N-E-S-W) does not affect the efficiency of the birch sap leak intensity or other tested physical sap properties: refraction, pH value, and percentage of dry matter. However, a slight effect on the electrolytic conductivity was found. Therefore, it can be summarized that the cardinal directions do not affect the usefulness of the sap for the production of birch syrup, but may affect a nutritional value.

Wild cucumber (Echinocystis lobata) is an invasive annual vine rapidly spreading across Central European riparian zones. Its success is linked to seed dispersal, with hydrochory expected to play a major role, but the specific mechanisms are not fully understood. This study examines whether E. lobata uses a dual dispersal strategy by seed morphological differences and hydrodynamic behavior, supporting both short-distance and long-distance dispersal. Seeds were collected in autumn and early spring, and analysed for morphology, buoyancy, and hydrodynamic properties. Over 150 seeds underwent biometric measurements: digital image correlation for swelling deformation, micro-computed tomography for internal structure, and hydrodynamic properties. Approximately 23% of seeds were buoyant, with buoyant ones present in both autumn and spring seed groups. Buoyant seeds had larger surface areas and internal air cavities, contributing to lower drag and enhanced passive transport in water. Using digital image correlation and micro-computed tomography imaging, we visualized seed coat swelling patterns and quantified internal structures. Hydrodynamic experiments revealed that buoyant seeds experienced lower drag and slower acceleration. Under oscillatory flow, buoyant seeds exhibited passive propulsion at 1 Hz, indicating a resonance effect facilitating dispersal during fluctuating water flow. These findings support a dual dispersal strategy: temporal seed release and buoyancy enable both local recruitment and long-distance dispersal, likely contributing to invasive success in riparian habitats.