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CommentsSwamp Rose Mallow has exotic oversized flowers that are very striking, particularly when they occur in a colony of plants. Other native Hibiscus spp. (Rose Mallows) in Illinois are similar to Swamp Rose Mallow in appearance and they are found in similar habitats. These species include Hibiscus lasiocarpos (Hairy Rose Mallow) and Hibiscus laevis (Halberd-Leaved Rose Mallow). Hairy Rose Mallow has felty leaves that are conspicuously hairy on both their upper and lower surfaces; Swamp Rose Mallow has leaves that are hairless (or nearly so) on their upper surfaces. Hairy Rose Mallow also has hairy ovaries/capsules, while the ovaries/capsules of Swamp Rose Mallow are glabrous. Sometimes Hairy Rose Mallow is regarded as a subspecies of Swamp Rose Mallow, or Hibiscus moscheutos lasiocarpos. The remaining similar species, Halberd-Leaved Rose Mallow, has leaves with divergent basal lobes (shaped like a halberd) or palmate lobes (maple-leaf shaped), leaf surfaces that are hairless on both the lower and upper sides, and seeds that are quite hairy. In contrast, Swamp Rose Mallow lacks such strongly lobed leaves, the lower surfaces of its leaves are canescent (or tomentose), and its seeds are hairless. In the past, the pink-flowered form of Swamp Rose Mallow that lacks a reddish purple throat was classified as a distinct species, Hibiscus palustris. However, it is now considered one of several color forms of Swamp Rose Mallow.