Natchez Trace Parkway Engine Module Supervisor Robert Vick, and staff members monitor a prescribed burn at Fort Hill in the Vicksburg National Military Park Monday. The supervised burns were to continue today in a program to help the overall maintenance of the park landscapes and control the spread of invasive plant species. About 56 acres were to be burned, providing a more historically accurate viewshed, National Park Service Natural Resources Program Manager Virginia DuBowy said.