For Thoreau, the literary excursion was both a spiritual and writing method. As a spiritual method, it allowed him to confront nature. In each confrontation, success for Thoreau was not defined by planning an itinerary but by the extraction of as much as he can (see my purpose statement) and in being as present as one is as the events of the excursion occur so as to see its wholeness. As a writing method, the excursion succeeds when it is able to convey this presence and wholeness through its imaginative rearrangement of events.
References
Buell, Lawrence. “Thoreau and the Literary Excursion.” Literary Transcendentalism: Style and Vision in the American Renaissance, Cornell University Press, 1973, https://www.jstor.org/stable/10.7591/j.ctt1g69x7r.14.
This gets at the heart of what the excursion meant for Thoreau, both in life and as a literary endeavor. It was a succession of confrontations with nature, from each of which the observer is expected to extract as much as he can, the mark of success being not so much in the planning of one’s itinerary or imaginative rearrangement of events as in the way in which he runs the gamut of events as they occur.