be sharpened is reduced by half moreover the construction employed does not require detachment of the chain links 1 from the device nor does it require disassembly of the links 1 from each other which facilitates maintenance it is preferred to form the underside surface of each of the knife members 7 to be of concave configuration so that when the chain is wrapped about the tree the inner surfaces of the knife member 7 will define a generally cylindrical configuration and will enable the limbs to be shaved in close proximity to the trunk as indicated at 9 the region of the underside of each of the knife members 7 in proximity to the cutting edges may be provided with an upwardly beveled region 9 to define a slight clearance between the cutting edge and the trunk to preclude the knife edges from penetrating the trunk itself the generally parallelogram configuration of the links 1 and the parallelogram configuration of the knife members 7 is such that the transverse cutting edges 7a 7b of the knife members 7 define a substantially continuous helical cutting line which circumscribes the tree trunk the cutting chain is mounted to a frame which includes a stationary support 15 which pivotally supports one end of the chain the stationary support member 15 includes an adjustment means 16 which enables the first end 13a of the chain.