This report is the result of the work of staff from many sections within the Forestry Commission and of the Princes Risborough Laboratory of the Building Research Establishment, Department of the Environment. In 1967 it was decided to undertake a comprehensive evaluation of the status and potential of the four most important “minor species” in British forestry, Western hemlock, Western red cedar, Grand fir and Noble fir. This report is based on the results of detailed assessments in stands selected to represent different sites and growth rates over the country as a whole, as far as this was possible from the limited range of stands of some minor species. These data have been combined with results from over 150 silvicultural experiments. Information on timber properties has also been summarised, using reports from Princes Risborough Laboratory (formerly Forest Products Research Laboratory) as an important source.