Trientalis L. was a genus in the Myrsinoideae tribe of the Primulaceae family with three species, but is included in Lysimachia L. sensu latu as of 2023. Members of the former genus occur in North America and northern Eurasia. The separation still feels useful, as the group shows a pretty unique morphology for Lysimachia. Species grow from rhizomes.
Lysimachia borealis (Raf.) U.Manns & Anderb, syn. Trientalis borealis Raf., is native to North American woodlands. Height range: 10-20 cm. The photos below were taken by Nhu Nguyen in the Upper Peninsula of Michigan.
Lysimachia europaea (L.) U.Manns & Anderb., syn. Trientalis europaea L., is native to the boreal regions of Europe and Asia where it grows in acidic forest and bog habitats. Rarely reaching 10 cm, it is the smallest species of the group. At sunny locations, the leaves develop an attractive bronze tinge like this plant grown in the bog garden of Martin Bohnet in southern Germany. As this is more southern than the usual range, they flower in early summer for him, probably a lot earlier than in their northern homelands.
Lysimachia latifolia (Hook.) Cholewa, syn. Trientalis latifolia Hook., is a fall and winter dormant perennial that grows from slender rhizomes with enlarged vertical tubers. It is a short plant of the shaded northwest forests with white to pale pink star-like flowers that appear in spring and is known by the common name of Pacific or Woodland Starflower. Height range: to about 30 cm. The first 2 photos were taken in May 2003 in Sonoma County, California by Bob Rutemoeller. The third photo was taken by Nhu Nguyen. The next two photos were taken by Mary Sue Ittner including a photo of three of the tubers on a 1 cm grid.
