Stems simple or nearly so, erect, pubescent, 1 to 3 feet high, from stout perennial roots. Basal leaves lyrately and interruptedly pinnate, petioled, the lateral segments generally few and small, the terminal one to three leaflets much larger, all sharply and irregularly lobed and toothed; stem leaves rather far apart, short petioled or sessile, simple or three-foliated. Flowers few, terminal, purple or purplish, nodding, three-fourths to 1 inch broad; petals obovate emarginate, abruptly narrowed into a claw; calyx lobes spreading, purple; head of the fruit stalked in the calyx; achenes pubescent, style jointed, plumose below, about one-fourth of an inch long.
In swamps and low grounds, Newfoundland to British Columbia, New Jersey, Pennsylvania, Michigan and Colorado; also in northern Europe and Asia. Flowering from early June until the latter part of July.
Memoir 15 N. Y. State Museum
Purple Or Water Avens - Geum rivale
There are several other Avens in New York, all except G. rivale with reflexed calyx lobes. G. Virginianum Linnaeus and G. cana-dense Jacquin have white flowers. G. vernum (Rafinesque) Torrey & Gray; G. strictum Aiton (described above), and G. meyerianum Rydberg, have yellow flowers. G. macrophyllum Willdenow, a boreal species found only in the Adirondacks, in this State, also has yellow flowers. For complete descriptions of these additional species the student should refer to Gray's Manual or Britton and Brown's Illustrated Flora.