The Forest Engineering Research Institute of Canada (FERIC), in cooperation with Winton Global Lumber Ltd. in Prince George, B.C., studied supported and unsupported winter skidding operations with conventional rubber-tired grapple skidders. In supported operations, skidders worked with track skidders and loaders that assisted with loading and decking, respectively. In unsupported operations, skidders worked alone. This report presents the study results, and discusses factors that influenced the productivities and costs of both skidding systems.