This report describes and discusses a harvesting system made up of commercially available equipment and modified farm tractors that has been successfully used to salvage and thin second-growth ponderosa pine stands. Commercial equipment consisted of fellerbunchers, a skidder, and a chipper. Farm tractors were equipped with grapples and metal reinforcings to adapt them to forest use.
United States Department of Agriculture, Forest Service, "Salvage and Thinning Operations in Second-Growth Ponderosa Pine Stands" (1983). Forestry. Paper 32.