Reforestation operations have historically seen a limited mechanization compared to logging and extraction operations. Hence, to improve work efficiency and reduce labor intensity in reforestation, an electric crawler-type barrow was developed that could be equipped with an electric auger. This machine offers high maneuverability and cross-country capability, allowing it to navigate steep and uneven terrains with obstacles, such as rocks and tree roots, while carrying a load of 60 kg. It stably traversed slopes of up to 30° , both in the uphill and lateral directions. Additionally, the loaded vehicle descended steep slopes at a controlled and safety speed. The machine was tested for the transportation and planting of container seedlings. The results indicated that transportation was 2.5 times more efficient than manual labor. Furthermore, planting achieved a work efficiency comparable to manual planting using dibble tools. Hence, simulations were conducted to determine the number of seedlings that could be planted in a day. The results indicated that using the electric crawler-type barrow allowed for planting a more significant number of seedlings as the distance covered increased. Moreover, the tasks of seedling transportation and planting were less labor-intensive and subjectively perceived to be less physically demanding than manual labor, as revealed by the assessments of the physical exertion level experienced by the participants.

We classified three simple cable logging systems using a static model to evaluate the retaining forces exerted on the carriage under load. The three systems differed in the number of boosting forces: single, double, and triple, according to the loading block pulley configuration of the carriage. Retaining forces were almost negligible in the single boosting system; however, they were significant in the double and triple boosting systems under tension, i.e., when the raised logs were located slightly downhill from the carriage. Retaining forces increased with the inclination of the skyline and were smallest in the single boostimg system and highest in the triple boosting system. The difference in retaining forces between the single and double boosting systems was greater than that between the double and triple boosting systems. A real-world test was conducted for a double boosting force arrangement using a live skyline cable logging system. The logging operation used a swing yarder to extract thinned whole-tree logs under partial suspension. Carriage retention forces were confirmed in all eight cycles. Pulling cable line tension forces were observed in the range of 1.4 to 7.3 kN just prior to the movement of the loaded carriage. The skyline tension at the top spar ranged between 9.3 and 20.1 kN, suggesting that the proper arrangement of guy lines would contribute to the efficiency and productivity of the system.

In forestry, the use of heavy machinery has been shown to reduce the infiltration rate of spur roads. During road construction, surfaces are compacted to improve the bearing capacity; it is possible that such compaction can reduce water infiltration. However, it is unclear whether the compaction level that achieves an appropriate bearing capacity allows adequate impermeability, since, unlike in most civil engineering contexts, hydraulic excavators are used for roadbed compaction instead of road rollers. Thus, this study aimed to clarify the bearing capacity and impermeability of the soil by simulating road compaction using a static load equivalent to that of a mini excavator used in spur road construction. To achieve this goal, the soil tank made of a U-shaped trench was filled with the test soil, and the soil was compacted with a static load. Soil hardness and unsaturated hydraulic conductivity were measured and analyzed based on their relationship with the number of compaction cycles. We found that soil hardness at the surface increased until three compaction cycles, equivalent to that obtained via a hydraulic excavator. The unsaturated hydraulic conductivity under 2 cmH₂O of suction did not change according to the number of compaction cycles. The measured conductivities were in the order of 10^-3 cm/s and between unlimited infiltration and impermeability.

Recently, the shortage of forestry professionals has become a significant problem. The use of small unmanned aerial vehicles (UAVs) and digital information has attracted much attention for solving this problem in forestry. Although various small UAVs and software have been developed, combining these tools to effectively reduce labor remains unclear. Therefore, this study aimed to investigate the amount of labor that could be saved using small UAVs, such as vertical takeoff and landing aircraft and rotary-wing aircraft, combined with tree measurement software, compared with conventional survey methods. Consequently, it was found that the measurement of tree numbers could reduce work time by approximately 70% and 84% in 5 and 10 ha, respectively. The efficiency of these tools is expected to improve further with increase in the survey area. The use of small UAVs and software is believed to contribute significantly as a potential tool for the shortage of forestry professionals.