work carried out directly at felling sites. Preliminary felling operations include inspection of the felling site, compilation of flow sheets and work organization plans, preparation of the felling site for exploitation, construction of shipping points (upper woodyards for temporary storage and shipment of the timber), installation of equipment, and construction of temporary logging roads.
The basic work includes production operations in processing and handling the felled timber—that is, felling, stripping, skidding the logs to shipping points, crosscutting the logs, and stacking and loading the products on logging transport. In the USSR tree-length logs account for over 70 percent of timber shipped from felling sites. With the development of initial processing of the wood at lower woodyards and reprocessing of low-quality timber and wood by-products into industrial raw material, an increase in the volume of felled and shipped trees is planned. Gradual selective cutting facilitates the processing of timber into lots at the felling site; at mountain felling sites, where transport operations with tree-length logs and trees are difficult, timber is also handled in lots.
Auxiliary log-felling operations include maintenance of heating and service facilities, maintenance and repair of machinery and equipment, and supplying of fuel and lubricants. In the USSR all log-felling operations are mechanized.
D. K. VOEVODA and V. I. ALIAB’EV