Abstract: An apparatus for severing the root system of a tree from the tree trunk during tree felling comprising a grapple mechanism for gripping the tree which, in operation, is clamped to the tree trunk and a cutting part suspended from the gripping mechanism for cutting the roots. The cutting part includes cutting knives arranged to encompass the tree trunk and movably mounted relative to the gripping part for cutting the roots. The power mechanism interconnecting the tree gripping mechanism and the tree cutting part moves the latter relative to the gripping mechanism in a direction longitudinally of the tree during a severing operation. The device may also be used to sever limbs from trees.