The efficient planning and control of timber harvesting operations is crucial to growth productivity and reducing costs, and different systems or methods are applied to obtain elevated performance. In particular, cable yarding is a highly appreciated and very efficient wood extraction method in areas that are difficult to access with ground-based extraction machines. Combined logging systems are not diffuse and not often implemented. For this reason, the use and the application of innovative methods are limited. However, some combinations have recently been observed in forest operations. This study, conducted in a deciduous stand in Bulgaria, paid attention to the combination of a tractor-mounted tower yarder (Valentini V400) with a clambunk skidder (Timberjack 1010D), aiming to examine the viability and develop the operational efficiency of the two-stage extraction system and to define the time, log volume extracted per unit by the yarder and the clambunk, and the yarding and skidding costs. The researchers carried out a time-motion study and performed a regression analysis to identify those variables that are most likely to affect the duration of work elements and productivity. For cost analysis, the COST model was used. The mean productivity of the tower yarder was 10.34 m³/PMH and 8.11 m³/SMH, while for the clambunk skidder, the productivity was 6.23 m³/PMH and 4.93 m³/SMH. The net costs for the combined logging system were calculated as 120.87 €/PMH and 14.93 €/m³. This study adds new data about the correct use of both machines, supporting their application in beech forests.

In Europe, long-distance transport of wood from landings to consumers is most often carried out by trucks and trucks with trailers. In forests located mainly in mountainous areas with rugged terrain and frequent curves, the construction of forest roads is complicated and often access for trucks with trailers is difficult or there is not enough space on the landing for maneuvers. In these cases, the truck leaves the trailer next to the public road and without it moves to the landing and loads the wood with Palafinger hydraulic crane model Epsilon Kran GmbH mounted on it, which it transfers to the trailer on the way back. Then, the truck moves to the landing to load itself, returns, hooks up the trailer and transports the wood to the customer. This study, conducted in a coniferous stand in Bulgaria, aimed to determine and develop models for the productivity and costs associated with transporting a truck with a trailer and to evaluate the suitability of this method. To study this very common method of long-distance transport, observations were made of 185 turns of a truck with a trailer operating with coniferous wood in Rila-Rhodope Mountain Massif, Southern Bulgaria. It was found that the duration of the working cycle is affected by the total mileage (average 65.41 km), the volume of the load and the number of logs. The productivity with and without delays, 7.80 and 7.30 m³/h, respectively, is affected by the mileage and the volume of the wood, while the corresponding transportation productivity (177.46 and 167.24 m³ km/h) is affected by the transport distance loaded and the volume of the load. To increase efficiency and reduce the cost of transporting wood over long distances, investments are needed to improve forest roads to eliminate the need to uncouple the trailer.

Wood modification is a process that alters the properties of wood through chemical, thermal, or physical treatments, thereby improving its performance, including durability and dimensional stability. Steaming is a hygrothermal treatment that can modify physical properties and may affect mechanical performance depending on process severity. This study investigated the effects of low-temperature steaming on olive wood ( Olea europaea L.) by applying a constant temperature (80 °C) and varying treatment duration (12, 18, and 36 h) compared with natural seasoning (control). Color and dynamic modulus of elasticity (MOE _d ) were measured on boards before and after treatment; after, specimens were tested for dimensional stability, bending properties (MOR and MOE _s ), compression strength, Janka hardness, and abrasion resistance. Steaming produced significant color changes in both heartwood and sapwood, with stronger responses in sapwood. Bending properties showed non-significant increasing trends, with mean MOR increasing from 50.21 MPa (control) to 62.24–64.71 MPa and the highest mean MOE _s observed in the 12 h group (+ 13.45% vs. control). Compression strength was comparable to the control (56.34–57.77 MPa). Janka hardness showed a decreasing tendency (up to − 21.3% in the 12 h group), while abrasion weight loss increased slightly and differed significantly among groups (0.21% in control vs. 0.24–0.29% after steaming). Overall, low-temperature steaming at 80 °C appears suitable for improving olive wood color uniformity and selected technological performance while limiting the mechanical degradation typically associated with high-temperature thermal modification.

In Mediterranean small-scale forestry, the adoption of highly mechanized CTL systems remains limited by fragmented forest lots, variable stand conditions, and high machine costs. This case study evaluated the operational productivity and economic feasibility of harvester-based felling and processing in two Mediterranean conifer stands in Southern Italy. A harvester was monitored in Calabrian pine and silver fir stands using a time-motion approach. Processing represented the dominant productive phase, while moving accounted for about one-third of productive machine time. Under the observed site conditions, the Calabrian pine showed higher gross productivity and lower unit time consumption than silver fir. The economic analysis indicated that feasibility was strongly dependent on gross productivity, benchmark motor-manual costs, and harvested lot volume, with more favourable break-even conditions in Calabrian pine.

A growing global demand for wood, coupled with the role of this material in low-carbon strategies, is fuelling interest in fast-growing plantations, including short-rotation forestry (SRF) and agroforestry systems. However, evidence of the physical–mechanical properties and possible uses of non-native hardwoods in the Mediterranean environment remains limited. This study aimed to address this current knowledge gap by evaluating the main physical and mechanical properties of six fast-growing non-native tree species cultivated in experimental plots in Calabria, southern Italy. The wood of Eucalyptus occidentalis Endl., E. × trabutii (M. Vilm. ex Trab.) A. Chev., E. camaldulensis Dehnh., E. bridgesiana R.T.Baker, Melia azedarach L., and Paulownia tomentosa (Thunb.) Steud., were evaluated. The dynamic elastic modulus (MOE_d) was estimated on standing trees using stress waves (TreeSonic™). In the laboratory, swelling and shrinkage (ISO 13061-14 and 16), static modulus of elasticity (MOE_s) and modulus of rupture (MOR) (EN 408), and compressive strength (ISO 13061-16) were determined. The data were analysed using one-way ANOVA, followed by Tukey’s HSD test where appropriate. Swelling and shrinkage showed no significant differences (p > 0.05). One-way ANOVA revealed a significant effect of species on MOE_s (p < 0.001). Both standing-tree stress-wave measurements (MOE_d) and laboratory tests (MOE_s, MOR, and compression strength) revealed significant variability in stiffness and resistance among the species examined. The positive relationship observed between MOE_d and MOE_s indicates that stress-wave testing can serve as a practical, rapid tool for ranking plantation material at an early stage, thereby supporting early decision-making in SRF and agroforestry systems. These results provide comparative evidence for species and clonal selection, and to optimise the allocation of plantation resources to targeted value chains in Mediterranean environments.