First thinnings are often neglected in Europe due to high harvesting costs. The studied small-tree bundler (Fixteri FX15a) was developed in order to rationalize the integrated harvesting of small-diameter energy wood and pulpwood in thinning operations, and to reduce transportation costs through load compaction. For the time-and-motion study, three stand types were chosen, all dominated by Scots pine (Pinus sylvestris). Two were dense, small dimension stands. The third stand was a "normal" first thinning stand. The machine fells and accumulates small-trees, which are fed into the bundling unit, where crosscutting, compaction, winding, scaling, and output of bundles of approximately 0.6 m3 solid is performed in an automated process. The productivityin the dense stand with rich undergrowth was 9.7 m'/PMh (productive machine hour), with an average tree volume of 27 dm3 and 3216 trees felled per hectare. In the dense stand with no undergrowth, a productivity of 11.9 m3/PMh was reached. The average tree volume here was 44 dm3, and 2019 trees per hectare were harvested. In the normal first thinning stand with no undergrowth, the felled trees averaged 84 dm3, 1266 trees per hectare were felled, and a productivity of 13.8 m3/PMh was registered. When compared with the previous version, the Fixteri II, the productivity of Fixteri FX15a was 2.1-2.3 times higher, depending on the density and size of the removal. Several factors may explain the increased productivity, but one of the most prominent is an improved technical potential for multi-tree handling.
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