Abstract: In a tree handling device, where the tree is fed longitudinally through at least three drive wheels driven by a fixed-displacement hydraulic pump, feeding commences with all drive wheels simultaneously propelling the tree longitudinally through the knife arms and frame. During feeding, once the approximate maximum feeding speed of the drive wheels is achieved, one of the drive wheels is shifted to a free-wheeling condition, allowing the maximum feed speed to increase.

Abstract: The disc saw blade has a plurality of teeth detachably mounted in sockets provided in a rim portion around the circumference thereof. Each tooth has an anchoring portion, and a cutting edge which projects slightly from the circumference of the saw blade. The sockets each have an anchor-receiving portion to receive the anchoring portion of a tooth. The teeth and the sockets are configured such that each tooth is installed by inserting its anchoring portion into a corresponding anchor-receiving portion of a socket, in an axial direction, and then securing the tooth to prevent axial removal, for example by making the anchoring portion cylindrical and rotating the tooth rearwardly about a center of the cylindrical anchoring portion to position a keyway on a key portion extending into the socket, or by using a bolt threaded into or through the tooth. Radial removal is prevented by the anchoring portion being shaped such that it cannot be extracted from the anchor-receiving portion, except axially.