Nodding trillium, like all members of the trillium genus, is a native North American perennial woodland flower. This isn’t just any trillium, it is the species Linnaeus used as the template for the genus. “Nodding,” because the flower hangs downward, facing the ground. They prefer wet, swampy deciduous or mixed deciduous and conifer forests.
Plants: A single stalk 6-24" (15-60 cm) tall, topped by a single flower.
Leaves: A group of three leaves (technically bracts) are evenly spaced around the top of the stalk. The leaves are sessile (attached), or nearly so. Each leaf is 1½-6" (4-15 cm) in size, somewhat wider than long, ovate but sharp-tipped.
Flowers: Each flower is white, cream, or rarely, pink, with three strongly recurved, oblanceolate petals. Each petal is ½-⅞" (1.5-2.5 cm) long. There are three lanceolate pale green sepals between the petals. Each sepal is about the same length as a petal, but not recurved. The top of the stalk bends so that the flower is facing the ground. Flowers appear from April to May to as late as July in northern climates.
Fruits: A single dark red, six-sided berry, up to 1" (3 cm) in diameter. The berry contains two or more seeds.
Edibility: Leaves are used to flavor soups or salads.
See also this Trillium comparison table.
Trillium cernuum at the U.S. Forest Service Celebrating Wildflowers site
Trillium cernuum on wisflora.herbarium.wisc.edu
Trillium cernuum on gobotany.nativeplanttrust.org
Trillium cernuum on Discover Life
Trillium cernuum on Wikipedia
Trillium cernuum description by Thomas H. Kent, last updated 20 Dec 2020.