Machines and techniques for skyline yarding of smallwood

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 initial cost) specifically developed for smallwood. Used, inexpensive yarders can be a viable option for yarding smallwood, but carriage selection and timber size are important considerations. Prebunching small logs with a separate, low-cost system can increase yarding production and lower harvesting costs incurred with expensive new yarders. Proper determination of crew size and equipment balance can produce more cost-effective use of new, low-cost yarders. Because smallwood logging will increase in the Pacific Northwest as log diameter continues to drop, additional research and evaluation to Improve the effectiveness of machines and techniques is essential.