Trees by their very nature are landmarks and memorials. They are therefore identified with human happenings. Trees also have more than the allotted life span of man and carry their association through generations of men and women. Thus they often figure not only in biography but also in history.

This bibliography is selective in character and includes references to books, articles printed in technical and other periodicals, and publications of societies. It covers the period from 1928 through May 1937. Traffic conditions changed considerably during this period, and material published prior to 1928 is now chiefly of historical value only.