At the beginning of the 20th century, ecologists began to promote a new way of seeing and a new understanding of plant science in terms of plant associations and vegetation communities. Early ecologists gave expression to this new way of seeing through a culture of photographic field practice. Through an active rhetoric of photographic representation in scientific publication, and in new field methods, they demonstrated a special relationship between photography and the procedures and experience of ecological fieldwork. Their methods reveal a fundamental relationship between visual practice and subjective experience in field science – as a productive complex for the construction of new knowledge. The quadrat method, in particular, developed and promoted by American ecologists Frederic Clements and Roscoe Pound in 1897, provides a model case for this reliance upon skilled vision. In the quadrat method and its photographic record, ecologists developed a technique for precise mapping and botanical quantification which, nevertheless, confirmed the importance of subjective judgement and skilled vision as the foundations for ecological knowledge and the development of a collective empiricism for ecology as a new discipline.