Comparison of mechanized systems for thinning Ponderosa pine and mixed conifer stands

Abstract

Three systems for thinning pine plantations and naturally-regenerated stands were studied. All three produced small sawlogs and fuel chips. The whole-tree system consisted of a feller buncher, skidder, stroke processor, loader, and chipper. The cut-to-length system included a harvester, forwarder, loader, and chipper. A hybrid system combined a feller buncher, harvester, skidders, loader, and chipper. Time-motion study data were analyzed to predict cost per unit volume. The cut-to-length system had higher costs and yielded less fuel than the other systems. In plantations, the hybrid system was least expensive, while the whole-tree system was cheaper in the natural stands. The harvesters were capable of handling larger-Trees in the natural stands, and could remove limbs from the plantation pines, up to a limit. The cut-to-length system could operate on the steep and broken terrain included in the study.

Citation

Hartsough, Bruce R.; McNeel, Joseph F.; Durston, Thomas A.; Stokes, Bryce J. 1994. Comparison of mechanized systems for thinning Ponderosa pine and mixed conifer stands. 1994 international winter meeting sponsored by the American Society of Agricultural Engineers. ASAE Pap. 94-7513. St. Joseph, MI; American Society of Agricultural Engineers. 20 p.