The black locust tree is a plantation-grown species that occupies a large area in Hungary. Due to variations in the growth environment of trees across different locations, the anatomical features of wood may differ. This study investigated the variability in fiber properties (fiber length, width, wall thickness, vessel length, and width) and growth rate of Robinia pseudoacacia L. from five counties and in three specific growing conditions. The parameters were investigated based on a sample of discs taken from the trees at breast height. The statistical analysis revealed significant differences in wood fiber and vessel dimensions, as well as ring width, between counties and growth conditions. Nearly all examined parameters showed the lowest values in Bács-Kiskun County, whereas the highest values were observed in Szabolcs-Szatmár-Bereg and Vas. Regarding the growth conditions, wood in poor growth conditions (mixed trees) and good growth conditions produced superior wood fiber properties and ring widths.

Robinia pseudoacacia L. has a valuable wood due to its natural durability and resistance to decay and external environments. This durability is attributed to its high content of extractives and the amount of tyloses in earlywood vessels. Given the widespread occurrence of black locust across Hungary, the wood chemical components may differ depending on site growth conditions. This research investigated the chemical extractives and color parameters of wood from Robinia pseudoacacia L. from different counties and growth conditions in Hungary. The relationship between chemical extractives and color based on the CIElab system was also analysed. The results indicated that both counties and growth conditions showed significant variations in chemical extractives and color parameters. The counties of Vas and Győr-Moson-Sopron exhibited the highest total contents of extractives, polyphenol, antioxidant capacity and intense lightness. Compatible outcomes were recorded under poor growth condition mixed species. Lightness was significantly associated with extractives from methanol-water and total phenol contents with lightness. While the extractive from the cyclohexane-ethanol solvent system was linked with all color parameters. Subsequent research will investigate the impact of extractives on wood durability under different locations and growth conditions.

The influence of growing site conditions on the chromatic properties of heartwood in black locust (Robinia pseudoacacia L.) cultivar ‘Nyírségi’ sampled from five regions of Hungary was investigated in this study. A total of 23 boards (average age of trees: 34.5 years) representing four site types were analyzed by instrumental colorimetry using the CIE Lab system. The overall average color coordinates were L* = 69.9 ± 4.0, a* = 4.0 ± 0.8, and b* = 27.4 ± 2.3. Significant chromatic differences were observed among site types proven by statistical analysis; however, no single site type consistently increased within-site color variability. Average total color differences (ΔE*) ranged from 3.94 to 6.31 across site types, corresponding to “noticeable” to “large” visual differences. Regionally, 89.1% of 55 specimen pairs exhibited clearly perceptible color variation (ΔE* > 2), with 61.8% classified as “large” (ΔE* > 5). Within-tree comparisons revealed ΔE* values of 3.72–3.75 under poor site conditions but <2.0 on good growing sites. The a* and b* components appear with measurable variations across all sites, while the characteristic yellow hue remains distinct and stable independent of site origin due to the high b* value.

This study provides an overview of the basic characteristics of Robinia pseudoacacia cultivated throughout Europe. After studying the literature, we concluded that air temperature and precipitation amounts significantly influenced the annual ring width of R. pseudoacacia. In addition, the light, water, and nutrient supply affected tree growth by increasing growth intensity, thus reducing vessel diameters and pieces per unit area. Black locust wood grown in Belgium has a higher volumetric shrinkage (16 %) and tangential shrinkage (8.8 %) and a considerably higher modulus of elasticity (15,700 MPa) compared to wood from Poland and Hungary. The vessel diameters measured in the latewood of Robinia wood grown in Hungary (70-140 μm) exceeded those in Greece (24 μm). Knowledge of the mechanical and physical characteristics of new black locust clones wood already in cultivation via breeding is incomplete. The same applies to climate change effects. The review article recommends that future research investigate the basic characteristics of new cultivars planted in different locations.

This papaer studiess the variations in moisture content within and among tree species of Sclerocarya birrea and Anogeissus leiocarpus, as well as the green density of a cubic meter of freshly felled wood from this species. The trees included in this research grew in Western Kordofan State, Sudan. Following their felling, tiny square samples of varying sizes (n=10) were gathered and weighed from each vertical position within the bole length (10, 50, and 90%). The results show that the average MC and the green density of the freshly felled wood were 109.97% and 686 kg/m3 for S. birrea, while the values of A. leiocarpus were 35.55% and 980 kg/m3, respectively. Furthermore, the findings of the analysis of variance revealed that the MC [%] varied significantly only between the tree species. Conversely, there was no significant difference in MC [%] within the vertical positions of the bole length for either species.

Robinia pseudoacacia L. wood is globally recognized for its high density, superior mechanical performance and low dimensional changes. Although widely cultivated across Hungary under diverse environmental conditions, potential regional variations in its wood properties remain insufficiently characterized. This study aimed to investigate the density, linear and volumetric shrinkage and swelling, modulus of rupture (MOR), bending modulus of elasticity (MOE) and compressive strength parallel to the grain (CS) of Hungarian R. pseudoacacia samples across five counties and under three growth conditions. Results indicated significant regional variations (p < 0.05) across some physical and mechanical parameters studied. The mixed stand in poor growth conditions showed significantly higher linear and volumetric shrinkage than pure stands under good and poor growth conditions. Also, the results revealed that samples from Bács-Kiskun county showed the highest density (0.84 g/cm³) and MOE (13.33 GPa). However, samples from poor growth conditions revealed the greatest density (0.81 g/cm³), MOR (131 MPa), and CS (71.90 MPa). These findings suggest that regional site conditions and environmental stressors play a critical role in defining the quality of R. pseudoacacia wood, offering valuable insights for localized forest management and enabling targeted site selection for high-quality timber production.