One of the ingredients of the Essiac cancer formula. Dried leaves act as a refrigerant and diuretic, and traditionally have been used to treat fevers, inflammations and scurvy. Use sparingly fresh in salads for a tart tangy taste. Antiscorbutic. Contains oxalic acid which can be toxic in large doses. Keep an eye on this plant as it can become quite invasive in acidic soils. Host plant for the Small Copper butterfly.