Theodore Roosevelt NP Vegetation Map contributes to advanced remote sensing research for mapping invasive leafy spurge in and adjacent to the park.
Leafy spurge is a highly aggressive and difficult to control herbaceous exotic plant.
It was first introduced at the park s western boundary in 1966 and now occupies approximately 10 percent of the total area of the South Unit. It grows in extensive, dense monocultures, often occupying entire sections of stream floodplains or smaller drainages. Although the plants grow in dense stands, openings in the canopy can expose litter and soil, adding to the challenge of mapping via remote sensing. The recently completed USGS-NPS Vegetation Mapping Program map at THRO has proven to be a valuable aid in this research because leafy spurge was one of the vegetation types included in the mapping process. The only other source of information was a 1993 map of leafy spurge, produced by the park in earlier efforts to generate baseline data to be used in control efforts.