Authors
Green PQ; Chung W; Leshchinsky B; Belart F; Sessions J; Fitzgerald SA; Wimer JA; Cushing T; Garland JJ
Source
For Sci 2020 Feb; 66(1):82-96
Abstract
Cable-assisted (or tethered) mechanized harvesting has recently been introduced to the Pacific Northwest of the United States, and is rapidly being adopted by the forest industry. However, potential environmental impacts, productivity and cost of the new harvesting systems have not been well-assessed. This study aims to examine the effects of cable assistance on soil compaction, system productivity and cost through a field-based experiment. A harvester-forwarder system was used to thin a harvest unit on dry soils in western Oregon, with and without cable-assistance. We conducted a detailed time study during operations and collected soil measurements before and after machine passes. Machine productivity ranged from 28.75 to 92.36 m3 per scheduled machine hour, with resulting unit costs for untethered and tethered systems ranging from $13.19 to $18.13/m3. Our results showed reduced soil impacts in both extent and degree of soil compaction when cable assistance was employed. The reduced extent of soil impacts is attributed to a reduction in track wander owing to the operative tensions of the tether cable, and the smaller increase in soil density appears to be attributed to combined effects of initially denser soil conditions and reduced shear displacement as a result of cable-assistance.
Keywords
Logging industry; Risk factors; Slope stability; Forestry; Environmental impacts;
Author Keywords: steep terrain; soil impacts; tethered assist system; machine rates; harvesting
Document Type
Journal Article
Funding Type
Cooperative Agreement
Identifying No.
Cooperative-Agreement-Number-U01-OH-010978; Cooperative-Agreement-Number-U54-OH-007544
Priority Area
Agriculture, Forestry and Fishing
Source Name
Forest Science
Performing Organization
Oregon State University - Corvallis
