The invention concerns an arrangement for the bundling of elongated tree parts (5) and similar forestry material to form manageable units, comprising a reception arrangement (10) for the collection and orientation of forestry material in a longitudinal direction, a binding arrangement (15) that fixes the material in a compressed condition through binding it, one or several pairs of grippers (37), each one of which demonstrating opposing gripper and compression arms (37A, 37B) which surround and compress the material transverse to its longitudinal direction, several supports (13:1, 13:2, 13:3) on which the binding arrangement and the gripper and compression arms are controlled such that they can be displaced in reciprocating motion in the longitudinal direction, an operating arrangement (14:1, 14:2, 14:3) arranged at each support (13:1, 13:2, 13:3). For the bundling of forestry material with improved control and monitoring, the arrangement comprises two supports (13:1, 13:2, 13:3) that can move independently of each other in the longitudinal direction, a length measurement arrangement with which the positions of each support (13:1, 13:2, 13:3 ) along the longitudinal direction can be detected, a position sensor (41A, 41B) with which the pivoted position of opposing gripper and compression arms (37A, 37B) can be detected.