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Greater sage-grouse have experienced declines due to numerous factors, causing them to be considered for listing under the Endangered Species Act. One of the main factors is thought to be habitat alteration and fragmentation caused by conifer encroachment, but little research has been done specifically to evaluate the effect. For example, western juniper distribution in the Great Basin has increased ~10-fold since pre-European settlement, but, although juniper management is becoming more widespread, little is known about how juniper encroachment and management may actually affect sage-grouse. Our goal was to assess specific effects of juniper encroachment and management on nest-site selection at multiple spatial scales. We analyzed high resolution spatial data of individual juniper trees in proximity to >300 nests in southern Oregon to determine important spatial scales and effects of juniper characteristics from 0.2 ha to 400 ha on nest-site selection. Our results indicate that various scales are important to sage-grouse nesting habitat and increased juniper coverage restricts nesting habitat. This information will be vital in determining how conifer encroachment effects sage-grouse populations as well as informing management. Studies evaluating the effects of conifer encroachment, such as this, will be integral to the Fish and Wildlife Service ESA listing decision in Fall 2015.