Trientalis borealis is a perennial herb, summer-green, 10-20 cm tall, roots associated with vesicular-arbuscular endomycorrhizal fungi (Berliner and Torrey 1989); colonial from rhizome, most reproduction is vegetative (Bierzychudek 1982), new rhizome initiated during June, can vary from 5 cm to 1 m, forms a tuber during July-Aug. in which leaves and flowers of following season will develop, tuber formation initiated by shortened photo period, later in season cool-night temperatures decrease respiratory rate and enhance carbohydrate storage (Anderson and Loucks 1973).
Leaves in one whorl of 5-9 below flowers, 3-10 cm long, lance-shaped, flowering starts when leaves are almost fully expanded.
Flowers white, radially symmetrical, ca 1 cm wide, 7 parted, self-fertile (Anderson and Loucks 1973) but usually pollinated by bees; blooms May-June.
Fruit dry, a capsule ca 0.2 cm long, matures in July, capsule wall splits exposing 2-14 white seeds; fruit may persist through winter (Anderson and Loucks 1973).
Wetland status: FAC.
Frequency in NYC: Very infrequent.
Habitat: Moist, undisturbed woods, swamp forest margins, shade tolerant.