Family changed from Trilliaceae to Melanthiaceae.

Plants of the World online, Kew Science http://plantsoftheworldonline.org/taxon/urn:lsid:ipni.org:names:542553-1 Link

Trillium sessile L. Trilliaceae Distribution: North America. Various Trilliums were used by Native Americans to stop haematuria, haematemesis, menorrhagia, and to heal ulcers (Milspaugh, 1974). Roots were eaten to treat stiff muscles, and tea from the plant drunk and powdered plant put on joints for rheumatism by the Iroquois (Lewis & Elvin-Lewis, 2003).

Oakeley, Dr. Henry F. (2013). Wellcome Library notes. Link

Northern America, North-Central U.S.A.

Northern America, Northeastern U.S.A.

Northern America, Southeastern U.S.A.