They say first impressions always matter. Americans acquired an empire of tropical islands in the Pacific about which they knew little and cared even less. Yet they set to almost immediately to understand and harness these new environments for their own purposes. This paper looks at the processes through which these strange new worlds in the Philippines and Guam were incorporated and subordinated into a comprehensible imperial framework through the diaries of two environmental managers, Gifford Pinchot and William Safford. Both men wrote about their first encounters with the tropics, recording its strange flora and fauna, noting its seismic convulsions and climatic extremes, and trying to manage it by making sense of what they saw, heard, smelt and touched. As diarists, scientists and, above all, imperialists, they give us rare insight into the initial attitudes of the men who managed these new imperial landscapes.