Quercus nigra pumila Marshall
Quercus rubra nana Marshall
Quercus banisteri Michx.
Quercus discolor banisteri (Michx.) Spach
Quercus nigra ilicifolia Kuntze
Quercus nana (Marshall) Sarg.
Quercus pumila Sudw.
Common Name: Bear Oak
Quercus ilicifolia is a deciduous shrub or a small tree that can grow up to 6 metres tall[
]. The plant spreads at the roots and often forms dense thickets[
The tree has been harvested from the wild for local use as a medicine and possibly also as a food. It is a very valuable wildlife habitat and can be used in soil restoration projects. It is often grown as an ornamental.
Scrub Oak is an important co-dominant of sand barren communities in the northeastern United States, additionally extending into sandy barren and mountainous habitats through the mid-Atlantic region into southern Ontario. Though the sand barren communities it characterizes are increasingly rare (threatened by fire suppression and disrupted disturbance regimes), Quercus ilicifolia remains locally abundant. The plant is classified as 'Least Concern' in the IUCN Red List of Threatened Species(2013)[
All parts of the plant contain tannins. Whilst tannins are found in many foods, and have a range of medicinal uses. They are usually only present in low concentrations. In some foods made from oaks (particularly the seeds), the tannin content can be quite high unless the food is treated to reduce tannin content.
Tannins are only of low toxicity and, because of their bitter taste and astringency, are unlikely to be eaten in large quantities. However, if they are taken in excess, they can cause stomach pains; constipation followed by bloody diarrhoea: excessive thirst; and excessive urination[
Eastern N. America - southern Ontario to Maine, south to North Carolina
Dry, sandy soils and open rocky outcrops on dry mountain, upland, barren, and slope sites; at elevations up to 1,500 metres[
|Conservation Status||Least Concern
|Other Uses Rating||
|Cultivation Status||Ornamental, Wild
Quercus ilicifolia is a very cold-hardy plant, tolerating temperatures down to around -25°c when dormant. It grows best in areas with hot summers. In areas with cooler summers it does not fruit well. Annual rainfall is around 1,100 - 1,200mm[
Requires a sunny position[
]. Requires a well-drained soil[
]. It is found in the wild on sandy, rocky, well-drained, nutrient-poor soils[, usually on soils with a low pH1050].
Quercus ilicifolia is a thicket-forming plant, forming a cluster of stems from a spreading rootstock. Individual stems are short-lived and grow slowly with a typical life span of 20 - 30 years; however, the root system is reportedly long lived and may support several generations of these short-lived stems[
Mature seed production requires 3 growing seasons. Flower buds are produced in the first growing season, flowering occurs in the second growing season with immature acorns being produced in the autumn of the second season, but they do not mature until the third growing season[
The plant resprouts freely from the base if it is cut down or top-killed by fire[
Quercus ilicifolia reportedly hybridizes with Quercus coccinea, Quercus falcata, Quercus imbricaria, Quercus marilandica, Quercus phellos, Quercus rubra, and Quercus velutina[
The acorns are an important food source for black bears, turkey, grouse and other species of wildlife[
Quercus ilicifolia is a crucial component of northeastern sand barren communities, particularly scrub oak-heath shrublands and pitch pine-scrub oak woodlands, which are rare community types facing major declines due to fire suppression and development of land. These sand barren communities provide important habitat for numerous wildlife species, notably rare species of birds and moths in southeastern Massachusetts[
Quercus ilicifolia can be found for sale in commercial nurseries for cultivation as an ornamental plant[
The ovoid to subglobose seed is 9 -16mm long and 8 - 11mm wide[
]. A bitter taste[
Although we have no specific information for this species, the seeds of all the species of oak are edible - indeed, several species have been used as staple foods, whilst most if not all have been used for food in times of shortage, when better foods were not available[
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.
The Iroquois considered Quercus ilicifolia very helpful in treating gynecological problems[
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[
]. Extracts of the plant can be added to ointments and used for the healing of cuts[
The plant is an early successional species that depends on stand disturbance, particularly periodic fires. It has been successfully used in a rehabilitation project on the Fresh Kills Landfill on Staten Island, New York, and may warrant consideration in other revegetation projects. Before planting seedlings, the site was covered with a 40cm layer of highly compacted clay-shale subsoil to minimize gas and water exchange with landfill contents. Next the site was covered with a 75cm layer of sandy mineral soil and a small amount of composted leaf mulch. Of the 65 bear oak planted, 33 were reproductively mature by the first year following planting, and 2 new bear oak seedlings emerged[
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[
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[
The bark of oak trees is also usually rich in tannins and can be used as a dyestuff and for waterproofing rope[
The wood of many Oak species is a favoured fuel - burning well and giving off a lot of heat[
Seed - it quickly loses viability if it is allowed to dry out. It can be stored moist and cool overwinter but is best sown as soon as it is ripe in an outdoor seed bed, though it must be protected from mice, squirrels etc. Small quantities of seed can be sown in deep pots in a cold frame. Plants produce a deep taproot and need to be planted out into their permanent positions as soon as possible, in fact seed sown in situ will produce the best trees[
]. Trees should not be left in a nursery bed for more than 2 growing seasons without being moved or they will transplant very badly.