Felling of natural forest trees in West Papua Province is carried out mechanically using a chainsaw by applying a selective cutting silviculture system. This study aimed to determine the elements of working time, productivity, and cost of felling as well as factors influencing felling activities using the chainsaw in the tropical natural forests in West Papua, Indonesia. The felled trees are dominated by the meranti wood species group with a minimum diameter of 45 cm. The average volume of the felled tree is about 4.205 m3/tree. The result showed that total felling time ranged from 15.3 to 18.3 min/tree with an average of 16.7 min/tree. The effective felling time was 11.8 min/tree (70.86%) and the delay time was 4.9 min/tree (29.14%). Felling time in making undercuts was on average 1.7 min/tree (9.98%), longer than back cuts time of 1.10 min/tree (6.39%). Total felling time was influenced by various variables: tree diameter, buttress height, and slope. Felling productivity was accounted for between 14.901 m3/h and 17.067 m3/h (15.778 m3/h on average). Felling costs ranged from 3.366 USD/h to 3.473 USD/h with an average of 3.407 USD/h or equivalent to 0.209 USD/m3 to 0.238 USD/m3 with an average of 0.225 USD/m3. To improve the effectiveness of felling time and productivity, this study suggests (1) upgrading the skills of the chainsaw operators through formal or in-house training in felling techniques, and (2) ensuring chainsaw operators bring a tree distribution map completed by field conditions information.
9 December 2023 in Jurnal Manajemen Hutan Tropika (Journal of Tropical Forest Management)
Felling and skidding are essential in the timber extraction process. But on the other hand, residual stand damage can’t be avoided. This study aimed to analyze the impact of conventional and improved felling and skidding techniques on residual stands in natural forests. Three observation plots were developed to identify the types, numbers, and criteria of residual stand damage due to both techniques. The criteria were categorized as a) minor damage (<25%), b) moderate damage (25–50%), and c) major damage (>50%). It showed that the conventional felling and skidding technique caused damages of 14.92% dominated by tree crown damage and 16.70% dominated by stem wounds, respectively. The residual stand damage due to conventional felling and skidding technique was 31.62% categorized as medium damage. Meanwhile, improved felling and skidding techniques caused damage of 9.89% dominated by broken trees, and 10.27% dominated by stem wounds, respectively. The residual stand damage due to improved felling and skidding technique was 20.16% categorized as minor damage. The improvement techniques can minimize residual stand damage by 36.24%.Therefore, a good understanding of forest concessionaires regarding RIL principles is necessary for achieving sustainable timber harvesting