Parts Most Frequently Used: Nut, Bark, Gall, Leaf

Flavors/Temps: Very Bitter, Slight Warming, Astringent

Caution: Due to high tannin content only use oak bark internally for no longer than four weeks. Not recommended for pregnant women.

Key Constituents: Nuts – Tannins, Protein, Carbohydrates, and Fat. Galls – Gallotannic acid, Tannins, Vitamin A, Vitamin C, Iron, Protein, Fiber, Calcium. Bark – Tannins (including Ellagitannin), Saponins (including Triterpenoids), Octyl gallate, Polyphenols, Resin.

History/Folklore: History/Folklore: Oak is a symbol of strength and endurance. It has become the national tree for many countries, including Bulgaria, France, Germany, Jordan, Latvia, Poland, Wales, and, as of 2004, the United States. Germany puts the oak image on its coins. The Ancient Greeks identified it with Zeus (King of Gods), and in Celtic times, the name of the oak tree was part of the name for druids, which meant strong, firm, strong in knowledge, or “knower of the oak tree”. Oaks were also associated with the god of thunder.

The Latin name “Quercus” is thought to derive from the Celtic words that mean “fine tree.”

An extract made of the bark of the species Q. crassifolia has been shown to fight E. coli and other bacteria that can cause stomach problems and diarrhea. The German Commission E has approved oak bark as a treatment for diarrhea, and the U.S. Pharmacopoeia listed it until 1916 for its astringent and antiseptic properties. Studies on oak bark in Russia confirmed it as the most effective remedy for preventing staphylococcal infections, making it a possible focus for use against MRSA and other antibiotic-resistant infections.

Native Americans have used oak bark to treat a wide variety of ailments, including bruises, hemorrhoids, bowel problems, and bladder issues. They used the acorns to make flour. The Ojibwa Indians used red oak bark to support heart and bronchial health.

Oak galls are formed by wasps laying eggs inside or feeding on the branches of leaves of trees. Used as a medicine in a way similar to that of oak bark, the galls are food for jays, nuthatches, titmice, and other birds that enjoy the larvae of the wasps. Sometimes they are called oak apple galls, because they can look like small apples. The galls do not typically harm the tree.

Oak galls help improve the elasticity of tissues and skin. This includes tightening the vaginal membrane wall, skin, and bladder tissues. Extracts made from the galls will contain vitamin A and C, iron, calcium, and other antioxidants. Oak galls can also help to treat cysts.

Both oak bark and oak galls have antiseptic, astringent, anti-inflammatory, and coagulating properties. Oak galls are popularly used to make dye.

Oak bark powder can be applied externally to dry out sores, insect bites, and bruises.

The tannins found in the leaves, bark, and acorns can be toxic. The leaves and flower buds are especially toxic when they are opening in the spring. A type of tannin known as ellagitannin is known for improving the structure and function of the liver and heart. It can help reduce the impact of a high-carbohydrate or high-fat diet and has been shown to lower systolic blood pressure. Ellagitannin has anti-inflammatory, anticancer, antioxidant, prebiotic, and cardioprotective properties. In correct doses, the bark and oak galls make excellent medicines.

The acorns can be used in soups and cereals, or as a coffee substitute. As a coffee substitute, 1-2 cups daily can be used as a medicine to help regulate thyroid function, improve blood count, and counter iron deficiency that contributes to anemia. It has also been used to treat rickets in children, reduce gout and joint pain, ease menses, and improve digestive function. Acorns do not appear on an oak tree until it is 20 years old.

Oak trees are powerful contributors to a clean environment. They store carbon dioxide, and a single large oak can remove up to 10 lbs of toxins from the air each year. They are a source of food and protection for birds, bears, insects, spiders, and many other species.

Oak woodlands host more than 160 species of birds and contribute to the health of over 2,000 plant species. Their large canopies help cool the ground and block high winds that can damage other growing plants. Their deep, wide root systems help stabilize soils, recycle nutrients, and generate biomass for other nearby plants. Their dead, fallen branches provide habitat for nesting birds, and bark for making medicine.

Oak wood is prized for furniture, flooring, and cabinet making. White oak has some water resistance, so it is considered the best choice for crafting wine barrels and boats. Red oak trees are more abundant, and their wood costs less than white oak.

White oak was used to build the hull of the famous U.S. naval ship, the USS Constitution, aka “Old Ironsides”, in 1797. She is the world’s oldest ship.