Distribution: Widely distributed on both sides of the Cascades crest in forested areas in Washington; British Columbia to California, east to Montana, Wyoming, and Colorado.
Habitat: Open to dense moist forests at low to mid-elevations, often where boggy in the spring.
Conservation Status: Not of concern
Glabrous perennial herbs from short, thick rhizomes, the flowering stem 1-3 dm. tall.
Leaves usually 3, whorled, at the top of an otherwise naked stem; leaves not mottled, sub-sessile, broadly ovate to deltoid-obovate, 5-15 cm. long and broad, pointed.
Flowers solitary, stalked, the peduncle 2-8 cm. long; sepals 3, green, narrowly oblong, 1.5-6 cm. long; petals 3, white, longer than the sepals and much wider; stamens 6, filaments 3-6 mm. long, anthers 6-14 mm. long, cream colored.
Fruit a fleshy capsule, yellowish, slightly winged.
T. ovatum is distinguished from our other Trilliums by its stalked flowers and sessile unmottled leaves. The leaves form a single whorl of 3 below the solitary flower.