Wood Sorrel and Yellow Wood Sorrel
Oxalis acetosella L. and 0. stricta L.
Small, low-growing perennials spreading from slender rhizomes. Stems of yellow wood sorrel are green-purple and smooth or only slightly hairy; those of wood sorrel have long hairs. Leaves are clover-like with three heart-shaped leaflets and are arranged oppvsge or in whorls on the stem. Several flowers with 5 petals occur on branched stalks. Those of yellow wood sorrel are bright yellow; those of wood sorrel are streaked and light purple. The fruit is a capsule that splits at maturity ejecting the seed. Wood sorrel blooms in June and July; yellow wood sorrel from May to October.