Marsh Milkwort. Polygala cruciata.
Milkwort Family. July - Sept.
A plant 3 - 12 inches high, found on margins of swamps, in low ground. Maine to South Carolina, and from Michigan to Minnesota and Nebraska.
Magenta, white or greenish, tiny, borne in terminal, clover-like heads.
Generally in whorls of 4. Plant stems square, branching.