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Home » Adopt a Piece of History » Map of the Rocky Mountain Region Showing Forest Areas and Irrigation Ditches in 1885.

Map of the Rocky Mountain Region Showing Forest Areas and Irrigation Ditches in 1885.

William Clements Library Adopt a Piece of History Bookplate

Map of the Rocky Mountain Region Showing Forest Areas and Irrigation Ditches in 1885.

Adopted by

Constance K. Olson


Charles E. Olson,  Jr.

Map of the Rocky Mountain Region Showing the Approximate Location and Extent of Forest Areas and Irrigation Ditches in 1885. Col. E.T. Ensign, Author. A. Hoen, Lithographer. Publisher: United States Department of Agriculture, Washington, District of Columbia, 1889. Color lithograph (31 × 18.75 inches).
Government document maps are not usually designed with the general public in mind. They are rarely colorful, never decorative, always functional and to the point. But they can reveal other stories about the land and its inhabitants. In this straightforward map of the forests and irrigation ditches in the Rocky Mountain area in the late 19th century, we also find chapters of the long narrative of removal and restrictions of Native Americans and also a baseline of natural resources in a region feeling the effects of climate change in the 21st century.
The map covers a region that includes the present day states of Montana, Idaho, Utah and Part of Nevada, Colorado, Wyoming, Arizona, and New Mexico, as they were in 1885. Forests are colored bright green and the network of canals running from major rivers are printed in red. Mountains and plateaus are labeled and shown graphically, without elevations. The numbered township and range grid of the Public Land Survey is present, as well as those areas excluded from that system: mountain ranges, national park (Yellowstone, established 1872), and Indian Reservations.

The designated Indian Reservations are identified with the names of the Native American tribes and in some cases the title and date of treaty establishing each reservation. One of the largest land areas set aside for Native American relocation is in the northern section of this map, where the Gros Ventre, Piegan, Blood, Black Feet and River Crow are labeled.

Although a large swath of forest runs roughly north/south overlapping the Atlantic and Pacific divides, few of the Native American reservations identified on the map enjoy these forested lands or the proximity of irrigation ditches. In fact, as one studies the map in more detail, it becomes clear that Native Americans were relocated to barren lands with little water.

In terms of climate change and water resources, this 1885 map provides useful benchmarks for evaluating the extent of remaining forests in the Rocky Mountain region today and measuring forest growth, deforestation, and the effects of acid rain and fires. The red irrigation ditches illustrate the relatively small scale of water diversion from the rivers of the Rocky Mountain region for agriculture and cattle ranches, another measure against which to assess current conditions of water diversion and water use, largely engineered by dams built subsequent to 1885.

Thus the acquisition of this demonstrates the importance of close study of a map and not allowing a dry title to prevent us from asking deeper questions.  Because the map was not made for the commercial market, it has been created as a document of record rather than a document of persuasion, making its impact in terms of people and resources all the more effective.