Sorrel contains high levels of oxalic acid, this is fine in small quantities, but in large doses oxalic acid can lock-up other nutrients, especially calcium, which may lead to mineral deficiencies.  Anyone who suffers from rheumatism, arthritis, kidney stones, gout, hyperacidity or anyone who is pregnant should avoid this plant as it can cause aggravation. Oxalic acid is also present in many foods you would buy from a supermarket, so please bear this in mind. Just because it's wild, doesn't mean it should be ignored totally.

Wood Sorrel Oxalis acetosella

Wood Sorrel Oxalis acetosella is a pretty little plant found mainly in the shade of ancient trees. Like common sorrel the leaves have a very sharp acidic taste, too sharp for some but perfectly acceptable to me. The stalks should not be consumed but the leaves are perfectly safe in small amounts (see common sorrel for oxalic acid details). These small green leaves are the perfect accompaniment to fish dishes, and even a sharp tasting tea can be made from them.

LEAVES - raw or cooked. A sharp tea can also be made from the fresh leaves.