About Circaea alpina L.
Leaf Characteristics
Circaea alpina L. has opposite, ovate leaves that measure 2–6 cm long and have coarse teeth along the edges. The petioles, which range from 1.5–4 cm (0.6–1.6 in) in length, feature a wing along their lower surface.
Inflorescence and Flowering Period
Flowers and fruits are grouped close to the top of the fruiting raceme; each raceme produces 15 or fewer white or pink flowers, blooming from mid-May through early September.
Flower Petal Traits
Every flower holds two white to light pink petals 1–1.5 mm (0.04–0.06 in) long, each divided into two lobes.
Flower Sepal Traits
It also has two white sepals that measure 1–2 mm (0.04–0.08 in) long.
Fruit Characteristics
Its fruit is a small bur that contains a single seed.
Reproduction Methods
C. alpina can reproduce both vegetatively through stolons and by seed.
North American Distribution
In North America, Circaea alpina grows across the entire range of Canada, and in the United States it occurs from North Carolina to Maine, and from New Mexico to Washington.
Eurasian Distribution
In Eurasia, its range covers Northern Europe, extending south to Albania and Bulgaria and east to Korea and Japan.
Habitat Preferences
This species favors moist, upland habitats.
Elevation and Specific Habitats
It is most commonly found in forests or near streams, at elevations from sea level up to 3,000 metres (10,000 ft).