The preparation of suitable sites for planting and growing of tree seedlings following logging is recognized by British Columbia Forest Service as a major silvicultural problem in the Central and Northern Interior regions of the province. Over the past few decades, scarification trials have been made with various types of drag and blade scarifiers. Substantial areas, particularly on the dry lodgepole pine (Pinus contorta latifolia) sites have also received mechanical scarification on an operational scale. The wet white spruce--alpine fir (Picea glauca ssp. glauca-- Abies lasiocarpa) sites, which often have a deep layer of undecomposed organic material on the forest floor, have traditionally been winter logged. The resulting accumulation of undisturbed duff, and logging slash, has normally been either windrow or broadcast burned. Some recent escape fires, e. g. the Eden Fire in the Kamloops Forest District in September 1973, caused considerable personal property damage, and have heightened interest in mechanical scarification as an alternative to prescribed burning. The author had occasion during the summer of 1974 to be employed by British Columbia Forest Service on a research project in the Prince George area entitled, Silvicultural Mechanical Site Preparation (S. M.S. P.). The purpose of this study was to measure and evaluate the performance of selected mechanical scarifiers, in producing an economically, and silviculturally acceptable level of planting site preparation. This report examines the findings of the S.M.S. P. project, and where appropriate, compares them with earlier Canadian forest scarification studies. Recommendations for the use of specific mechanical site preparation equipment are viewed both singly, and in combination with other forest management practices.