This publication discloses a harvester head (10) in a timber harvesting machine and a method therein, the harvester head comprising a body (14) with at least two support and feed members (16, 20) for timber (12) to be handled, the members supporting and transferring timber (12) in the longitudinal direction. The said members (16, 20) are arranged on different sides of the transfer track for timber (12). Of the support and feed members (16, 20), at least one is mechanically operated (16) and at least one is freely rotating (20). Further, the harvester head (10) comprises adjustment members (26, 28) for the reciprocal distance of the said support and feed members (16, 20), and power transmission members (34) for using at least one mechanically operated member (16). The said at least one freely rotating timber support and feed member (20) is provided with a revolution counter (18) for measuring the transfer range of timber (12).