northern starflower

(Lysimachia borealis)

Conservation Status
northern starflower
Photo by Luciearl
  IUCN Red List

not listed


NNR - Unranked

SNR - Unranked


not listed

Wetland Indicator Status
  Great Plains

FAC - Facultative


FAC - Facultative

  Northcentral & Northeast

FAC - Facultative


Northern starflower is a 4 to 8 tall, erect, perennial forb that rises on a single stem from a long, slender, creeping rhizome and fibrous roots.

The stems are erect, slender, unbranched, round in cross section, and hairless. There is a whorl of 5 to 9 leaves at the top of the stem and usually one or more much smaller leaves between the middle and the top of the stem.

The leaves in the whorl are short-stalked or stalkless, lance-shaped to lance-elliptic, ¾ to 4 long, ¼ to 1¾ wide, and widest at the middle. They are narrowly wedge-shaped at the base and taper to a point at the tip with straight or concave sides along the tip. They are pinnately veined with a single prominent midvein and several lateral veins that join at the end and do not reach the margin. The upper and lower surfaces are hairless. The margins are untoothed. The leaves lower on the stem, if any, are alternate, inconspicuous, 1 32 to ¼ long, 1 32to 1 16 wide, and often more or less scale-like.

The inflorescence is usually 1, sometimes 2 or 3 flowers rising from the upper leaf axils. Each flower is solitary at the end of slender flower stalk (pedicel). The pedicel is hairless but sparsely covered with stalked glands. It is ¾ to 2 long, usually shorter than the leaves.

The flower is 5 16 to 9 16 wide, flat, and circular. There are 5 to 9, usually 7 sepals, 5 to 9, usually 7 petals, and 5 to 9, usually 7 stamens. The sepals are green and are fused at the base into a short calyx tube, then separated into lance-shaped or lance-linear lobes that are longer than the tube. The petals are white and are fused at the base into a short corolla tube, then separated into widely spreading, egg-shaped to narrowly lance-shaped lobes that are longer than the tube. The petals are longer than the sepals and are pointed at the tip. The stalks of the stamens (filaments) are fused at the base.

The fruit is an globe-shaped capsule. It ripens in mid-summer.




4 to 8


Flower Color




Similar Species

  No similar species  

Moist. Coniferous forests, mature hardwood forests, bogs. Light shade.




May to June


Pests and Diseases






Distribution Map



2, 3, 4, 5, 7, 24, 28, 29, 30.









  Kingdom Plantae (green algae and land plants)  
  Subkingdom Viridiplantae (green plants)  
  Infrakingdom Streptophyta (land plants and green algae)  
  Superdivision Embryophyta (land plants)  
  Division Tracheophyta (vascular plants)  
  Subdivision Spermatophytina (seed plants)  
  Class Magnoliopsida (flowering plants)  
  Superorder Asteranae  


Ericales (heathers, balsams, primroses, and allies)  


Primulaceae (primrose)  
  Subfamily Myrsinoideae (cape myrtle)  


Lysimachia (loosestrifes)  
  Section Trientalis (starflowers)  

Starflowers were formerly placed in the genus Trientalis, which was part of the Lysimachia complex. A recent phylogenetic analysis (Manns & Anderberg, 2009) concluded that the genus Trientalis is invalid, and the species were moved to the genus Lysimachia, section Trientalis.


Subordinate Taxa






Trientalis americana

Trientalis borealis

Trientalis borealis ssp. borealis


Common Names


American starflower

northern starflower














The group of outer floral leaves (sepals) below the petals, occasionally forming a tube.



A collective name for all of the petals of a flower.



On plants: The thread-like stalk of a stamen which supports the anther. On Lepidoptera: One of a pair of long, thin, fleshy extensions extending from the thorax, and sometimes also from the abdomen, of a caterpillar.


Pinnately veined

With the veins arranged like the vanes of a feather; a single prominent midvein extending from the base to the tip and lateral veins originating from several points on each side.



A horizontal, usually underground stem. It serves as a reproductive structure, producing roots below and shoots above at the nodes.



An outer floral leaf, usually green but sometimes colored, at the base of a flower.

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  Starflower (Trientalis borealis)
Andree Reno Sanborn
  Starflower (Trientalis borealis)  

Primrose Family

  Trientalis borealis (Star-Flower)
Allen Chartier
  Trientalis borealis (Star-Flower)  



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Other Videos
  MyNature Apps; Identifying Starflower, Trientalis borealis

Uploaded on May 30, 2011

How to identify Starflower, Trientalis borealis also known as May Star, Star-of-Bethlehem and Broadleaf starflower.






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