This article compares Alexander von Humboldt's and John Ruskin's writings on landscape art and natural landscape. In particular, Humboldt's conception of a habitat's essence as predominantly composed of vegetation as well as judgment of tropical American nature as the realm of nature of the highest aesthetic enjoyment is examined in the context of Ruskin's aesthetic theory. The magnitude of Humboldt's contribution to the natural sciences seems to have clouded our appreciation of his prominent status in the field of art history. In addition to his position as scientist, Humboldt's role as aesthetician is demonstrated in this paper. Unlike Ruskin, who comfortably resides in the canon of art history relative to his minor significance in the field of geology, Humboldt has not been recognized for his impact on the world of art; his tremendous scientific importance seems to have overshadowed an appreciation of it.