Special thanks to lyda_pearl of Berlin, New Hampshire who submitted this image via the BPotD Submissions Forum on the garden's online discussion boards. The original thread and image is here. Many thanks – it's great to receive some images from eastern North America!
Native to eastern North America, painted trillium is found in forests with moist, nutrient-rich, acidic soils. Its epithet, undulatum, means “wavy”; the photograph aptly illustrates that the petal margins are the reason for that name.
A phenomenon mentioned in the entry on Cirsium vulgare (bull thistle) also applies to trilliums – many, if not all, trilliums (including Trillium undulatum) have their seeds dispersed by ants. In other words, they are myrmecochores.
Photography resource link: For inspiration, the photography of Paul Butzi. Paul has also written a number of articles worth investigating.
There seems to be a tendency for local slugs to zero in on species from outside PNW, leave native one alone. If I were trying T. undulatum here I would keep it baited.