1990 Map of Poison Creek

About this map

Mahogany Ridge and the volcanic landscape of Devils Garden define this high-desert region of Harney County as it appeared in the late 1980s. The drainage of the Silvies River anchors the southwest corner, where water management is evident at Fivemile Dam and the Arntz Reservoir. This 1990 provisional edition documents a network of family-held cattle operations, including the Thousand Spring Ranch, Hart Ranch, and Peterson Ranch, illustrating the persistent ranching economy of the Harney Valley outskirts. The map also records the Poison Creek (Site) and various spring-fed locations like Theimer Spring and Coal Pit Spring, which served as vital resources in a landscape carved by deep coulees such as Fenwick Canyon and Heifer Canyon.