Highlights• An important preoccupation in sustainable logging management is represented by the analysis of work time structure and productivity level in manual tree felling with a chainsaw.• Sound knowledge of the factors which influence work time allows better planning of harvesting operations so that deadlines could be met and damage to forest ecosystems be minimized. AbstractThe purpose of this research is to establish time consumption and productivity when using Husqvarna 365 chainsaw for resinous tree felling in mountainous regions. The research was conducted in the Romanian Southern Carpathians, in two mixed spruce (Picea abies (L.) H. Karst.) and fir (Abies alba Mill.) tree stands (S1 and S2). Only one team of workers, made up of a feller and an assistant, was used in the felling operation. This was divided into nine specific stages for which work times were measured. Work time structure used here includes WP -workplace time (PW -productive work time; SW -supportive work time, NT -non-work time) and NW -non-workplace time. The results indicated a productivity of 10.138 m 3 h -1 (4.55 tree h -1 ) in S1 and of 11.374 m 3 h -1 (4.33 tree h -1 ) in S2. Work time structure was WP 88.61% (PW 19.59%; SW 33.88%; NT 35.14%) and NW 11.39% in S1 and WP 83.77% (PW 17.66%; SW 30.73%; NT 35.38%) and NW 16.23% in S2. The results obtained showed that the power function best describes the relationship between productivity expressed by tree h -1 and breast height diameter (dbh) (R 2 = 0.89 in S1 and R 2 = 0.94 in S2). When productivity is expressed by m 3 h -1 the results obtained in the case of power, exponential and linear functions are comparable (R 2 = 0.65 to 0.67 in S1 and R 2 = 0.81 to 0.92 in S2). Productivity is also influenced by stump diameter and the distance between trees. Their influence on productivity was emphasized by linear regression equations.

This research established the time consumption, work time structure, and productivity for primary processing in felling areas of coniferous trees felled with a chainsaw. Delimbing and partial cross-cutting were taken into consideration. The research was conducted in a mixed spruce and fir tree stand situated in the Carpathian Mountains. The team of workers consisted of a chainsaw operator and assistant with over 10 years of experience. The results indicated a total time of 536.32 s•m −3 (1145.26 s•tree −1), work performance (including delays) of 6.716 m 3 •h −1 (3.14 tree•h −1), and work productivity (without delays) of 35.459 m 3 •h −1 (16.58 tree•h −1). The chainsaw productivity during tree cross-cutting was 82.29 cm 2 •s −1. Delimbing accounted for 96.18% of the real work time, while cross-cutting accounted for 3.82%. The time consumption for delimbing and cross-cutting, as well as the work productivity and performance in the primary processing of coniferous trees in the felling area, were influenced by the breast height diameter, stem length, and tree volume, while the chainsaw productivity was influenced by the diameter of the cross-cut sections. The relationships between the aforementioned dependent and independent variables were determined by simple and linear multiple regression equations.