This section is from the book "A Guide To The Wild Flowers", by Alice Lounsberry. Also available from Amazon: A Guide to the Wild Flowers.
Rose.
Purple.
Scentless.
North and west.
May-July.
Flowers: large; nodding; terminal; growing sparingly on the flower stems. Calyx: top-shaped, with five spreading lobes. Corolla: of five obcordate petals. Stamens and Pistils: numerous. Styles: long; curved. Fruit: a head of dry akenes. Leaves: pinnately-parted, the upper ones having usually three lobes. Stem: simple.
This is a pretty flower of the swamps and low grounds. Its purple colour is of a peculiar shade; as though it had been mixed on a palette from which the chrome yellow had not been scraped.

G. strictum, or yellow avens, has flowers that grow in panicles. They are innocent enough looking; but it is from their pistils that the prickles come out in the late season to test the temper of those wandering in their vicinity.
 
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