This study reports a floristic and landscape survey of Ft. Assiniboine Sandhills Wildland Park. The park spans about 6,600 ha and is located along the north side of the Athabasca River northeast of the hamlet of Ft. Assiniboine. Thirty person-days of fieldwork were conducted in June and August 1997; 48 0.03 ha plots were established and described; miscellaneous observations were made outside the plots. A total of 434 species of plants were found in the study area, of which 20 species (4.59%) are classified as provincially rare. Of the 20 rare species, 6 were vascular plants, 7 were mosses, and 7 were lichens. By taxonomic group, there were 258 vascular taxa, 90 mosses, 14 hepatics, and 74 lichens. The typical 0.03 ha plot contained 50.2 species (s.d. 18.9, median 49.5), with a maximum of 97 species and a minimum of 9 species/plot. Mean number of rare species/plot was 0.771 (s.d. 1.372, median 0). White spruce forests, typically represented by riparian old-growth forests along the Athabasca River, had the highest species richness/plot (mean 75.7 species vs. an overall mean of 50.2 species)--about 50% more species than the average plot in the study area. Mixedwood forests, typically old-growth riparian white spruce - balsam poplar +/- aspen +/- birch forests along the Athabasca River, stood out from all the others in supporting the most rare plant species (a mean of 3.0 species/plot vs. 0.771 species/plot overall). Pemmican Island is a hotspot for plant species richness and rare species richness. Conservation of plant species biodiversity requires that oldgrowth forests be protected from logging. The occurrence of provincially rare and otherwise noteworthy plant species is described. DCA ordination and TWINSPAN classification were used to differentiate plant communities and species groups. Five landscape types were found: eolian sand dunes; organic terrain; riparian complex; loess plain; and colluviating slopes. The most significant plant communities are riparian and non-riparian old-growth forests of white spruce and mixedwood; three types of grasslands (northern ricegrass, slender wheatgrass, western porcupine grass); and a diverse assemblage of wetlands ranging from marshes and rich fens to bogs. Management concerns relating to gas development, fire management, ORVs, nonconforming uses, and suggestions for trail development are offered.