Similar Species: Large Yellow Wood Sorrel is most likely to be confused with Yellow Wood Sorrel, but is a generally larger species (flowers up to 1 inch in diameter). The seedpods of Large Yellow Wood Sorrel are short and stubby in comparison with the elongate seedpods of Yellow Wood Sorrel. The leaves of Large Yellow Wood Sorrel are margined with purple. The leaves of Yellow Wood Sorrel may be blotched with purple, but not along the leaf lobe margins. The flower pedicels and stems of Large Yellow Wood Sorrel are usually bristly. The flower pedicels and stems of Yellow Wood Sorrel are smooth or slightly hairy.
Lucas Land
Great Wood Sorrel
Oxalis grandis
From Nearctica
Identification: Plant erect. Flowers yellow, relatively large (up to 1 inch in diameter), with 5 petals in an open rosette. Seedpods short and stubby, borne on a relatively short pedicel, the pedicels never bent. . Leaves with the astringent flavor of oxalic acid. Leaves, green, cloverlike with three lobes, the lobes each with an apical notch and a fold line through the center. Leaf lobes usually margined with purple. Stipules at the base of the leaf petioles absent. Plant 1 to 3 feet in height.
Distribution: Southern Illinois to Pennsylvania, southward to Georgia and Mississippi.