The trip was probably made in connection with the Nature Conservancy and was broad in its scope. Nicholson stayed in New York, Washington DC, Chicago, Madison (Wi), and Columbus (Oh). Organisations with which he held discussions included the Conservation Foundation and the National Audobon Society (both New York) and the National Planning Association (Washington). Much of his time was spent visiting various National Parks, such as Shenandoah National Park (Virginia), and wildlife refuges. He was also able to meet leading American conservationists including H. Coolidge and I. N. Gabrielson.

Typescript revised version of the diary in MS. 15041/1376 with manuscript revisions. The diary contains many observations, points and impressions and may have been submitted as a report.