Method of forest harvesting and a machine for performing said method

A method for felling standing trees and cutting portions from the felled trees, utilizing a vehicle having a front end and a rear end and an extendable and retractable boom which has means for gripping, cutting and lowering standing trees, the vehicle further having a delimbing device at the rear end thereof, the boom being rotatable independently of the delimbing device around a substantially vertical axis at the vehicle front end, the method comprising driving the vehicle forward up to a stand of trees, extending the boom substantially over the front end of the vehicle toward a tree, gripping the tree with the boom, cutting the tree, then retracting the boom and swinging the boom around its substantially vertical axis, with the severed tree stem held substantially vertically, to a position where the boom is pointing substantially over the rear end of the vehicle, then lowering the tree substantially in the longitudinal direction of the boom with the tree top directed backward away from the vehicle, introducing the root end of the tree into the delimbing device, and delimbing the tree while advancing the tree from the rear end of the vehicle toward the front end thereof, and during a first phase in which the delimbing device assumes a first position at an angle to the longitudinal axis of the rear vehicle section, feeding delimibed logs out in cut or whole lengths over one side of the vehicle, then swinging the device so that its delivery end is directed to a hopper located between the delimbing device and the vehicle front end, and then feeding cut logs to the hopper during a second phase.