Oak tree properties

This article was endorsed by Elisenda Carballido - Dietitian nutritionist. Postgraduate in Phytotherapy and master in Nutrition and Metabolism.

(Quercus robur)


Common English name: Oak, English oak, French oak

Common name in other languages:

Spanish: Roble, roble atlántico, roble inglés, roble carballo.

French: Chêne pédonculé

Catalan: Roure pènol.

Gallego: Carballo común

Portuguese: Carvalho-alvarinho, carvalho-vermelho,carvalho-roble.

Italian: Farnia

Euskara: Haritz kanduduna

German: Stieleiche.

Danish: Stilk-Eg

Dutch: zomereik

Polish: Dąb szypułkowy

Finnish: Metsätammi

Scientific name: Quercus robur L.

Family. Fagaceae

Habitat: Where does oak tree live?

European tree from Atlantic climate forest. It appears as a cultivated in gardens, hedgerows, tree seats, etc.

Oak description

oak drawing

Oak drawing with an acorn and a leaf

Evergreen tree of the Fagaceae family up to 45 m in height.

Erect stems with the bark full of cracks and wrinkles, light gray in youth and darker as the tree gets older.

Leaves alternate, lobed, sessile, with rounded lobes and very short petioles, provided with two auricles at the base larger than the petiole up to about 12 cm.

Flowers in catkins, yellow-green color.

Fruit in nut (acorns), gathered in groups of 1-3 on the same stalk.

Very curious are the galls produced by these trees. These are excrescences produced by oaks so that they can inhabit different parasites, without damaging the wood of these trees. They are formed by the interaction of hymenoptera cynipid insects with oak. In the oaks, these gills, in the form of balls, are known as “gallarita” or “gallaruto”.

Harvesting and conservation of bark, gills and oak leaves

The bark should be collected in spring and the leaves in summer. They should be dried in the shade and kept in bags of clothing in a cool and dry place.

Can oak acorns be eaten?

Some oaks produce sweet acorns that can be eaten, although in many cases they are bitter and are not consumed, or they have to be debittered. In nature, acorns are necessary to feed forest animals (squirrels, birds, …), or for some insects to complete their life cycle.

Detail of an oak fruit (acorn) and leaves.

Detail of an oak fruit (acorn) and leaves.

Components of oak

  • Tannins (20% bark, 10% leaves): Gallic acid, catechol, pyrogallol. The maximum concentration in tannins occurs in specimens of more than 10 years.
  • The gills of the oaks also have tannin (tannic and gallotanic acid, 20%) and can be used in phytotherapy.
  • Flavonoids: quercetin, catechins, gallocatechins, leucocyanidin, leucodelfinidin (bark)
  • Soluble fiber: Pectin (bark)



a big oak

Appearance of a large, majestic oak (Quercus robur L.)

Historically, oak (Quercus robur L.) has always been highly appreciated, both for its uses in natural medicine, and for its great ecological importance (it is estimated that an oak can be colonized by more than 500 species of insects).

  • Oak medicinal properties are derived from its richness in tannins and flavonoids that provide it with astringent, antiseptic, anti-inflammatory and hemostatic properties.

There are many plants that contain tannins, but what characterizes the oak is that it has one of the most potent tannins and in more concentration, which makes it one of the best astringent remedies.

Oak astringent properties

The astringent properties of oak are due to the presence of tannins (gallic acid) and catechins. It is called astringent to any substance that constricts body tissues. It is primarily used in two ways:

  • Internally to reduce secretions, reduce swelling and stop bleeding.
  • Externally to “dry” skin, tightening the tissue or blocking fluid.

Hemostatic properties of oak tree

It is called hemostatic to any compound capable of retaining blood flow. In natural medicine the hemostatic properties of certain plants are used to stop bleeding. In natural medicine these properties are used for the following conditions:


Oak bark decoctions for the digestive system

Oak bark decoctions are suitable for the digestive system abnormalities as they can neutralize excess secretions which can cause numerous problems such as:

  • Diarrhea: This plant can stop diarrhea by reducing the excess of fluid in the gut, which is useful if colitis or diarrhea. (Decoction of a teaspoon of ground bark for each glass of water. (5 g.) Drink 3 cups a day).

For childhood diarrhea some acorns can be toasted and pounded into a powder. Make a decoction of 3 gr. per cup of water.

  • Gastritis: It helps improve the symptoms of the disease, by acting on an inflamed gastric mucosa. Gallic acid, besides being astringent, has antiinflammatory properties because of flavonoids. (Decoction of a teaspoon of ground bark for each glass of water. (5 g.) Drink 2 glasses)

Do not exceed the dose and avoid treatment for ulcers because this plant can aggravate the disease. If a worsening, stop taking it and consult a doctor. The plant contains betasitosterol having ulcerogenic properties.

  • Intestinal bleeding: People with intestinal bleeding can take the same mixture, provided that they have been diagnosed by a doctor and their ulcers do not present an evil character

Astringent properties of oak bark for urogenital disorders

  • Urinary incontinence: The astringent properties of this plant can avoid this derangement (Decoction of a teaspoon of bark per cup of water for 10 minutes (three small glasses a day)
  • Vaginal flow: The preparation above may be useful for the treatment of vaginal discharge.

Properties of acorns to lower cholesterol


Photo of acorns.

For many years, acorns have served as food for humans, as have chestnuts. Currently, its consumption is relegated to those who still do not have the palate accustomed to the flavors of modern food.

Certainly, acorns have the taste of a somewhat bitter, astringent almond, due to its tannin content. Said components can also be used for medicinal purposes, since they are foods that lower cholesterol, and, for all the aforementioned, they are also very suitable for diarrhea. In addition, acorns are rich in healthy fats and carbohydrates, they provide healthy energy for the body. See how to collect and consume acorns.

medicinal properties of oak

Main medicinal properties of oak and its benefits in natural medicine

Oak bark remedies for external use

Wealth in tannins and flavonoids gives the bark of this plant antiseptic, anti-inflammatory, astringent and hemostatic properties, which can be exploited for treating a number of conditions including:

Detail of an oak trunk

Detail of an oak trunk. The bark of this tree is purchased in herbalists and is used with medicinal properties.

  • Pharyngitis: It reduces inflammation of the pharynx and helps eliminate germs that cause inflammation. (Decoction of 5 0 6 tablespoons of crumbled dried bark per liter of water. Make gargling)
  • Sore throat: The same treatment is suitable to gargle in order to treat swollen tonsils.
  • Rectal or anal problems: These same properties can be helpful in the treatment of rectal problems such as healing of hemorrhoids (Use the previous preparation to mix with water and perform sitz baths). Also for anal fistulas. (Decoction of a teaspoon of dried bark per cup of water. Wet a towel with the liquid and apply on fistula).
  • Problems of the gums: The gums are body tissues that cover the teeth and portions near jaws. These tissues are subject to possible inflammation (gingivitis) with a clear disposition to bleeding (bleeding gums). (Mouthwashes made from macerating one tablespoon of fresh bark in a liter of red wine for 4 days help reduce gum inflammation and stop the outflow of blood)
  • Mouth sores: Same rinses may be useful in the treatment of mouth sores.
  • Nosebleeds: Oak is one of the best hemostatic, able to stop the flow of blood. This property can be used to stop nosebleeds in the even of epistaxis or frequent episodes of bleeding from the nose. (Crumble a bit of dry oak bark. Convert it into powder with a coffee grinder. Take a speck of dust between your fingers and insert it into the nose.)
  • Cracks in the skin: The astringent properties of oak help to close the cracks in the skin in people who are prone to the formation of these grooves when their skin is very dry chapping, cracks on breasts, cracked anus, etc. (Decoction of a spoonful of dried bark per cup of water. Apply the liquid to the affected area two or three times daily)
  • Chilblains: Its astringency may be suitable for the treatment of chilblains (decoction of 200 g of dried bark per 4 liters of water for ¼ hour. Cool and realize hands or feet baths with the resulting liquid)
  • Inflammation of the vulva: Very useful in the treatment of vulvitis. (Make vulva baths with the liquid from the decoction of a spoonful of dried bark per cup of water.)

Can oak consumption be dangerous?

Oaks and related plants of the genus Quercus have a very high amount of tannins, especially in the bark, where it can reach up to 20% and a smaller proportion in the leaves and fruits (acorns)

The tannins are irritating for the intestinal mucosa can cause vomiting and even ulcerations. It is recommended, therefore, to use preparations for internal use only under supervision of the physician and never exceed the recommended dose.

Internal preparations should never be taken in case of gastroduodenal ulcer. Treatments for internal use should not be prolonged longer than 4 days.

External use applications must not be performed on very large wounds or extend them beyond 15 or 20 days. Patients who present infections, fever or heart problems should not perform any baths treatments with this plant.

punto rojo More information on oak.

Written by Editorial Botanical-online team in charge of content writing

16 September, 2019

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This material is for informational purposes only. In case of doubt, consult the doctor.
"Botanical" is not responsible for damages caused by self-medication.

Botanical-online is an informative page that describes, among other topics, the traditional uses of plants from a therapeutic point of view. Their descriptions do not replace professional advice. Botanical-online is not responsible for self-medication and recommends consulting with the physician.