ABSTRACT Sweet-scented Indian-plantain, Hasteola suaveolens (L.) Pojark., is a species of special concern in 13 states and jurisdictions in the eastern United States and occurs predominantly in riparian habitats. In the Allegheny National Forest (ANF) of northwestern Pennsylvania, H. suaveolens is considered a species with viability concerns. I surveyed riparian plant communities in the Allegheny River Islands Wilderness (ARIW) of the ANF to provide information on the habitat affinities of H. suaveolens useful for conservation and management needs. Hasteola suaveolens was located within 13 of 42 survey sites on six of the seven islands in the ARIW and occurred in three riparian community types: a floodplain scour community dominated by native herbaceous plants an Acer saccharinum–Platanus occidentalis floodplain savanna community and a Platanus occidentalis–Carya cordiformis (Wang.) K. Koch–Ulmus rubra Muhl. floodplain savanna community. Occurrences of H. suaveolens were largely associated with elevated floodplain geomorphic surfaces having moderately drained to well-drained soils that were located above high energy scour zones.