This study was conducted to examine the coefficient of drag resistance (µ) between a log and bare forest soil during partial
suspension yarding. Drag resistance in this study was defined as the resistance due to friction between the soil and the log plus the resistance due to the plowing action...
This study compares production rates and costs for four ground skidding machines and for four harvesting treatments. The four
machine types studied were a Caterpillar 060 crawler (060), Caterpillar 518 rubber tired skidder (RTS), FMC 200 CA (FMC), and
International TD-8E crawler (TD-8E). Two treatments, conventional/whole tree and designated/tree length,...
Although one of the most common problems facing the forest manager is the determination of management regime, there has been little effort to explicitly recognize the effect of harvesting technology and topography in the analysis. This study introduces a unified theory in harvesting in mountainous terrain which brings together silvicultural...
Timber harvesting is a common activity on many small woodland
properties. Whether a harvest is large or small, landowners
must carefully evaluate their overall goals and objectives before
beginning. A well-conducted harvest will help realize those
goals, but a poor job may lead to disappointing results that have to
be...
Yarding delays add significantly to the time and cost required to obtain a given quantity
of timber. In this study, they increased total yarding time by as much as 28 percent. As yarding system complexity increases, the frequency of delays can also be expected to increase. For one balloon yarding...
Research on skyline machines and techniques currently available for yarding smallwood is reviewed. Three categories of machines are discussed: used yarders (with a low initial cost) adaptable to smallwood, new and versatile yarders (with a high Initial cost) manufactured in the United States, and new, foreign-built yarders (with a low...
Timber harvesting in the Pacific Northwest (PNW) region of the United States of America (USA) has a long history of explosive growth, environmental litigation and regulation, economic downturn, and workforce dynamics that have created a current environment where cable-assisted harvesting is quickly gaining popularity among private and public land managers...
This paper describes a mathematical formulation and a computer program
in basic language for analyzing the load carrying capacity of skyline
systems using the effects of log drag. The actual log and ground geometry
are used in the analysis of the payload capacities for standing, live and
running skylines. The...
