Medicinally, the barberry falls within the field of the "Doctrine of Signatures" in that, the wood of the stems being so vividly yellow, it was obvious to all that it would cure jaundice - which back then was called the yellow disease. One of its common names, Jaundice Berry, derives from this belief. Yet, however ridiculous this doctrine may have sounded, there seems to have been some truth in the association, for a most modern herbal from England says of barberry:
Tonic, purgative and antiseptic. Used in all cases of jaundice, liver complaints, general debility and biliousness. It regulates the digestive powers, being a mild purgative, and removes constipation ... The berries make a pleasant acid drink of great utility in diarrhea, fevers, et cetera. Note from Jane: I guess I start to wonder when the same herb is said to be useful for diarrhea and constipation. Just doesn't seem logical, but then again, I'm just reporting about these things, not taking this from personal experience.
The root, the root bark and the berries are used. Several writers recommend an infusion of 1/4 to 1/2 teaspoonful of the powdered bark taken three to four times daily, while the juice of the berries makes a pleasant and healtful acid drink. Note from Jane again: I'm glad to hear that the berries aren't poisonous like my parents told me when I was little, since I'm sure I tasted some of them while playing out in the yard - just to be mischievous.
The berries in the fall make an excellent jelly or pickle; beautiful in color and fine with meat dishes. In Herbal Simples, Fernie says that the jelly is an excellent relief for catarrhal infections, and that the plain juice, with a little sugar, is a healing gargle.
This purely European plant has established itself throughout the northeastern tier of the states. It is easily found, in spite of the fact that the first legislation against the barberry was passed in 1670, and the plan has been fought and grubbed out ever since. the common (not Japanese) barbery harbors the spores of a wheat rust which really makes it an enemy in the wheat-growing states. I have occasionally come across one here in our woods, but have never seen is as invasive, at least in our woods. I expect it wants a bit more sun like the Japanese Barberries of which I grow a dozen or so cultivars (photo at top - Berberis gilgiana). Although most of ours are rather large bushes and wouldn't be suited for a small garden, I have recently acquired some truly miniature ones, a gold and a red leaf, though right now, I'm not sure of their names. They are easy to grow and care for and can be pruned if they get a bit too large. There are deciduous and evergreen types, but all have lovely yellow flowers with the most delicious honey scent in the spring. Fall berries are a fine food for the birds once they have been frosted a bit.