Fl. Boston. ed. 2, 182. 1824
Subspecies 2 (2 in the flora).
Plants infected with an anther smut, Microbotyrum stellariae (Sowerby) G. Deml & Oberwinkler [Ustilago violacea (Persoon) Roussel, in the broad sense], exhibit flowers with enlarged, reddish anthers. This condition is known in both subspecies, especially in northern areas of the range, but is as yet unknown in Stellaria calycantha, a species previously united with S. borealis by some authors.
|1||Sepals ovate to ovate-triangular, with midvein extending to near apex, lateral veins visible only at base; capsules dark brown, opaque, less than 2 times as long as wide, usually 3-4.5(-5) mm; leaf blades elliptic-lanceolate to narrowly elliptic or linear-lanceolate, widest just below middle, usually 2-3 cm; circumboreal||Stellaria borealis subsp. borealis|
|1||Sepals narrowly triangular, with 3 prominent, ridged veins extending to near apex; capsule straw colored, translucent, 2 times as long as wide, usually 5-7 mm; leaf blades narrowly lanceolate, widest near base, usually 3-6 cm; w North America||Stellaria borealis subsp. sitchana|