Using lichens to assess air quality on public lands is increasingly common, serving as a budget friendly supplement to widely spaced monitoring networks like NADP and IMPROVE. Two common lichen species, Letharia vulpina and Usnea lapponica, were collected from the Bridger Wilderness less than 30 km from a concentration of active oil and gas wells in Sublette County, WY. Lichens accumulate nutrients, such as nitrogen, in excess of metabolic needs, making tissue levels a reflection of atmospheric nitrogen levels. The main objectives were to calibrate nitrogen levels in lichen with co-located nitrogen measurements and determine the extent of nitrogen dispersal into the wilderness. Overall nitrogen levels were relatively low although visual signs of damage to lichens were seen at the highest deposition sites. The results demonstrate that lichen tissue indicators are a simple, accurate tool for nitrogen monitoring.