عنوان مقاله [English]
Tree felling is one of the most important component among tree harvesting components which consists of cutting and felling, limbing and bucking sub-stages. Tree limbing using chainsaw in hardwood forest is much effective and important. This research was carried out in two compartments of Namkhaneh district, in KheyrudForestfor assessment of limbing sub-stage. The objectives of this study were time study of tree limbing operation, estimating the productivity and costs of chainsaw and developing regression model. Factor affecting total limbing time regression model was dbh of harvested tree. The hourly production of chainsaw limbing with and without delay time were 11.1 m3/h (4 tree/h) and 14.8 m3/h (5 tree/h), respectively. Productivity of chainsaw tree limbing is increasing with dbh as power. The unit cost of chainsaw limbing with and without delay time were 14710 and 11020 Rials/m3, respectively. Total tree limbing cycle time without delay averaged 12.37 minutes and with delay time averaged 16.51 minutes and also with reducing personal delay, work efficiency can be increased.