Piper applied a scientific eye to his artistic output. He often gathered measurements and local history for subjects like the White Pine or the Redwood. His work lacks the romanticised flourishes found in other nineteenth-century botanical art. He prioritised the structural anatomy of bark and limbs. This methodical style provides a factual record of North American forests before the period of heavy industrialisation.

Collectors today appreciate these prints for their clarity and historical weight. The monochrome etchings suit modern spaces that require natural themes without unnecessary decoration. Pieces such as "Ash Forest in Maine" provide a quiet atmosphere. They present the physical reality of the American wilderness through the observations of a man who preferred empirical accuracy to artistic invention.