The name may sound a little odd, but in the timber industry feller bunchers are serious business. Feller bunchers are used to clear cut standing groves of trees and then stack the felled logs onto special sleds called skidders for removal. Some feller bunchers use powerful hydraulic shears to clip smaller diameter trees, while others use oversized chainsaw blades or large rotary saws to slice through larger ones.
Most feller bunchers utilize one of two chassis designs, depending on the conditions on the site. Light to medium duty feller bunchers use a rubber-tired tractor chassis, similar to backhoes. Heavy duty feller bunchers or those working in muddy or uneven fields may use tracked designs also found on bulldozers. Many well-known manufacturers of farming equipment, including Case, John Deere and International Harvester, also make feller bunchers for the timber industry.
In the field, feller bunchers perform most of the same duties as human lumberjacks. Trained operators drive their feller bunchers into one end of a stand of trees and switch on the cutters or saw blades. Each tree is held in place by a hydraulically-controlled clamp as the blades cut through the tree close to ground level. The tree is then maneuvered to a skidder, essentially a giant sled which can be attached to a tractor and dragged to another area for processing.
Whenever a forestry agency orders a thinning of an existing grove, feller bunchers are generally used to minimize damage. Trees can be cut in place and moved out without collapsing on other inhabitants of the forest. Feller bunchers are also useful for wholesale removal of trees from construction sites. They can literally plow through an entire stand of trees in a few hours. Blades can also be adjusted to cut off trees at any selected height.
Much of the heavy equipment used in the logging or timber industries can be dangerous, but feller bunchers have acquired a reputation for being especially hazardous to operate. It is impossible to predict precisely how a large tree will react after being cut, and operators of feller bunchers are often placed at ground zero. The weight of the tree may pull the entire machine off the ground or errant branches may suddenly enter the driver's compartment. The saw blades may become enmeshed in a tree, requiring a dangerous extraction. While in operation, feller bunchers cannot be rendered completely safe. For this reason, many logging operations try to limit the number of workers in the vicinity of a feller buncher in action.
By Michael Pollick