The light brown, ovoid to narrowly ovoid or ellipsoid seed is 12 - 18mm long and 8 - 12mm wide[270 ]. Although no direct reference of edibility has been seen, this species belongs to the white oak subgenus, where the seeds are generally low in tannins and are often eaten[1050 ]. The seed is usually cooked before eating, though it can also be eaten raw. It can be eaten whole, though it is more commonly dried, then ground into a powder and used as a thickening in stews etc or mixed with cereals for making bread. In some species, especially many of those classified as 'white oaks', the seeds are low in tannins and have a more or less sweet and agreeable flavour. The seed of most species, however, have a very bitter flavour, due especially to the presence of tannins. In these species there are various processes that can remove or at least reduce the amount of these bitter substances (although other water-soluble substances, including some minerals, will also be removed). Tannins are water-soluble and therefore the easiest way to remove or reduce tannin levels is by soaking in water. A few different methods are listed:- A traditional method of preparing the seed was to bury it in boggy ground overwinter and allow the wet soil to gradually leach the tannins. The germinating seed was dug up in the spring when it would have lost most of its astringency and bitterness. Another method was to wrap the seeds in a cloth bag and place them in a stream for several weeks. Drying the seed and grinding it to a powder before soaking speeds up the process. The fastest method is to use hot water, by cooking the powder and changing the water several times until the cooking water is no longer bitter. Alternatively, you can use cold water (which is reported to produce the best quality flour). In this case, you soak the powdered seed in cold water for 12 - 24 hours then discard the water. Repeat this process for a number of times until the soak water is no longer bitter. The roasted seed of many Quercus species has been used as a coffee substitute. Gray oak (Quercus grisea), a member of the beech family (Fagaceae), is a hardy southwestern native that produces edible acorns. Like all oaks, its acorns contain high levels of tannins when raw, which can cause digestive upset and must be leached out before the nuts are safe to eat. The acorns of gray oak are relatively large and of good quality, though still somewhat astringent when fresh. Once shelled, coarsely ground, and leached with repeated changes of water, the nutmeats become palatable and lend themselves well to cooking. The nuts are whitish inside with dark-brown shells, and after processing they are well suited for making breads, pancakes, or porridge. Roasting the leached nutmeat brings out a more nutty, pleasant flavor while driving off moisture, making them suitable for long-term storage. The harvest typically occurs toward the end of summer into autumn, when acorns mature, although timing can vary with elevation and rainfall. While they require effort to process, gray oak acorns are a reliable and worthwhile wild food resource [2-3].

Plants For A Future can not take any responsibility for any adverse effects from the use of plants. Always seek advice from a professional before using a plant medicinally.


Quercus (oak) species are used in the traditional medicine of many cultures, being valued especially for their tannins. Various parts of the plant can be used, most frequently it is the leaves, bark, seeds, seed cups or the galls that are produced as a result of insect damage. A decoction or infusion is astringent, antibacterial, antifungal, antiseptic, styptic and haemostatic. It is taken internally to treat conditions such as acute diarrhea, dysentery and haemorrhages. Externally, it is used as a mouthwash to treat toothache or gum problems and is applied topically as a wash on cuts, burns, various skin problems, haemorrhoids and oral, genital and anal mucosa inflammation[4 ]. Extracts of the plant can be added to ointments and used for the healing of cuts[4 , 1231 ].

The leaves of most species in this genus are more or less rich in tannins. A mulch of the partially decayed leaves can be placed around vulnerable plants in order to repel slugs, snails, grubs etc, and these will in time break down to add humus and nutrients to the soil. Fresh leaves should be used with caution, however, since as these decay they utilize some of the nitrogen in the soil and thus can inhibit plant growth[20 , K ].. Oak galls are excrescences that are sometimes produced in great numbers on the tree and are caused by the activity of the larvae of different insects. The insects live inside these galls, obtaining their nutrient therein. When the insect pupates and leaves, the gall can be used as a rich source of tannin, that can also be used as a dyestuff and is also used by many cultures to make ink[4 , 331 ]. The bark of oak trees is also usually rich in tannins and can be used as a dyestuff and for waterproofing rope[331 , K ]. The wood is hard and heavy. Because of its usually small dimensions it has little commercial value, though it is used as fence posts and, when larger sizes become available, it is used to make furniture[1050 ] The wood is used for fuel[1050 ].

Special Uses