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Hypericum ascyron L.

Great St. John's-wort

Habitat: Moist rich soil, riverbanks. [Non-tidal rivershore (non-forested, seasonally wet); Forested wetland].

Range: Northern Maine to Manitoba, south to western New England, New Jersey, Ohio, Indiana, and Missouri.

Aids to Identification: As an herb in the St. John's-wort genus, H. ascyron displays the characteristic 5-petaled, yellow flowers and opposite, punctate leaves. It is unique within its group because of its large flowers (2.5-3.0 cm wide), large leaves (5-12 cm long), and 5-locular capsules.

Ecological characteristics: Very little is known about the ecological characteristics of this species in Maine.

Phenology: Flowers July - August.

Family: Clusiaceae

Synonyms: Formerly known as Hypericum pyramidatum Ait.

Known Distribution in Maine: This rare plant has been documented from a total of 2 town(s) in the following county(ies): Aroostook, Penobscot.

Dates of documented observations are: 1951, 2002

Reason(s) for rarity: Disjunct from principal range.

Conservation considerations: The only known population in Maine occurs along a powerline right-of-way. It is unclear how maintenance of the powerline will affect the population.