Technical Abstract: Aerial color photography was used in 1993 to map Leafy Spurge (Euphorbia esula) infestations occurring within Theodore Roosevelt National Park, Medora, ND. Results indicated that 1:10,000 scale photography was effective in identifying and mapping spurge clumps occupying an area greater than 1 square meter. Other findings included the predictable nature of new spurge stand establishment and development, as well as the total estimated acreage of leafy spurge for the park. New photography was acquired in 1998 and is currently being analyzed. This paper will compare and contrast the findings of the 1993 and 1998 efforts for the area of the park west of the Little Missouri River. Specific findings, concerning the changes in leafy spurge distribution, extent, and the ability of aerial photography to quantify the dynamics of the leafy spurge community, will be presented.