Graduation Date

Spring 2018

Document Type



Master of Science degree with a major in Natural Resources, option Forestry, Watershed, & Wildland Sciences

Committee Chair Name

Han-Sup Han

Committee Chair Affiliation

Community Member or Outside Professional

Second Committee Member Name

Daniel Opalach

Second Committee Member Affiliation

Community Member or Outside Professional

Third Committee Member Name

John-Pascal Berrill

Third Committee Member Affiliation

HSU Faculty or Staff

Subject Categories



Cut-to-length (CTL) harvesting systems have recently been introduced to the redwood forests of California’s north coast. These machines are being used to commercially thin dense redwood (Sequoia sempervirens) stands which tend to form clumps of stems that vigorously sprout from stumps after a harvest. One of the challenges is to avoid damaging residual trees which can decrease productivity, increase costs, and lower the market value of trees. The goal of this study was to evaluate the productivity and costs associated with CTL systems used in a redwood forests and use that data to develop equations for predictions. Time and motion study methods were used to calculate the productivity of a harvester and forwarder used during the winter and summer seasons. Regression equations for each machine were developed to predict delay-free cycle (DFC) times. Key factors that influenced productivity for the harvesters was tree diameter and distance between harvested trees. Productivity for the harvesting ranged from 28.8 to 35.6 m3 per productive machine hour (PMH). For the forwarders, the number of logs per load and travel distance were important factors affecting productivity. Forwarder productivity ranged from 22.4 to 23.3 m3 per PMH. Total stump-to-truck costs for CTL harvesting system ranged from US$17.1 to $22.8 per m3.

Citation Style