This book has been prepared to meet a growing demand on the Forestry Branch for publications. Of this kind. In it are described over one hundred tree species native to Canada, including all the commercial species and many of minor or no economic importance. Several of the species described are ordinarily little better than shrubs but are found in arborescent form somewhere in their natural range of occurrence. No distinct line can be drawn between trees and shrubs. They grade one into the other. Many trees are reduced to mere bushes when growing under unfavourable circumstances.