Abstract

Optimizing productivity and costs and minimizing negative impacts on soil properties is a pre-requisite in forest harvesting. We conducted research aimed at assessing the effects of four harvesting systems on productivity, costs and soil compaction in a small forestland. The systems used in the yarding were: (1) a forwarder-harvester system, (2) a rubber-tire skidder, (3) a farm tractor, and (4) a bulldozer, using chainsaws for felling activities. A continuous time and motion technique and cost study analysis were used for predicting productivity and costs of each harvesting system. Additionally, soil compaction was measured in trafficked and untrafficked areas in the skid trail and in the harvested plots. The results showed that the forwarder system reached a greater productivity in terms of cubic meters per productive machine hour (11.45 m3/PMH) with a production cost per unit (7.54 $/m3), and caused less compaction on the forest soil (0.86 g/cm3). On the other hand, the bulldozer system caused the greatest soil compaction (0.97 g/cm3), with a lower productivity (4.64 m3/PMH) and higher production cost (11.73 $/m3), similar to the farm tractor systems. The results have important implication for the selection of machineries for small-scale forestry harvesting, as well as, implications for sustainability management and forest soils conservation. © 2022, Steve Harrison, John Herbohn.