The data include ages and locations of presence/absence surveys for sagebrush (Artemesia tridentata) on the Bureau of Land Management Rio Grande del Norte National Monument, New Mexico. We sampled cross-sections of sagebrush along 11 General Land Office section survey lines and conducted growth ring analysis to produce inner-ring dates for 93 sagebrush plants. The presence/absence surveys were conducted along the same section lines as the growth ring samples and were compared to the original surveys from 1881 to assess vegetation change on the landscape.