Quercus prinoides and Quercus muhlenbergii are closely related and have sometimes been treated as subspecies of one species. They are treated here as distinct for the following reasons:- Quercus muhlenbergii is found on calcareous soils whilst Quercus prinoides occurs on sands (often acidic) and dry shales; seedlings of Quercus prinoides can flower and produce acorns in as few as 3 - 5 years from planting, when only 20-50 cm tall, and maintain their dwarf, clonal habit in cultivation, whilst Quercus muhlenbergii begins fruiting as a small tree of 3 metres or more tall[
Quercus acuminata (Michx.) Sarg.
Quercus alexanderi Britton
Quercus brayi Small
Quercus castanea Muhl.
Quercus castanea macrophylla Hampton
Quercus prinoides acuminata (Michx.) Gleason
Quercus prinoides alexanderi (Britton) Steyerm.
Quercus prinus acuminata Michx.
Quercus rubra muehlenbergii (Engelm.) Wenz.
Quercus sentenelensis C.H.Mull.
Common Name: Yellow Chestnut Oak
Quercus muehlenbergii is a deciduous tree with a broad, rounded canopy; it usually grows around 18 - 30 metres tall, though on favoured sites it has reached 48 metres and on drier sites it is sometimes a shrub around 3 metres tall[
]. The straight, cylindrical bole usually branches from quite low down; it can be up to 120cm in diameter on favoured sites
The tree is harvested from the wild for mainly local use as a food, medicine and source of materials. There are conflicting reports on the uses of the wood, but it is probably harvested on a commercial basis. It is sometimes grown as an ornamental, making an attractive shade tree[
This species has a wide distribution across the United States and into parts of Canada and Mexico. Although population size has not been quantified, it is not believed to approach threshold values for a threatened category. 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[
Central and eastern N. America - Iowa to Vermont, south to New Mexico, northern Mexico, Texas and northern Florida
Dry calcareous slopes and ridges, or on rich bottoms[
]. Favouring alkaline soils and avoiding acid soils, it grows on limestone outcrops and well-drained slopes of the uplands, usually scattered with other hardwood speciess[
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Quercus muehlenbergii is a very cold-hardy tree, tolerating temperatures down to around -30°c when dormant. It grows best in areas with hot summers. In areas with cooler summers, such as the maritime regions of the temperate zone, it often grows poorly, failing to properly ripen its wood and suffering frost damage over the winter[
Grows best in a sunny position[
], though young plants tolerate reasonable levels of side shade[
]. Prefers a good deep fertile, well-drained loam which can be on the stiff side[
]. Succeeds on clay and alkaline soils[
]. Found in the wild on dry, rocky sites, such as calcareous bluffs, rocky hillsides, and protected slopes and canyons. It also occurs in glades and valleys, and along rocky streambanks[
]. It tolerates moderate exposure, surviving well but being somewhat stunted[
]. Established plants are very drought tolerant[
This species is localized throughout its range and seems dependent upon soil type and pH above 6. It readily reproduces by sprouting.
Growth is fairly rapid for an oak[
], especially when the tree is young, though it slows down with age[
]. It can take up to 30 years before the tree starts to produce acorns[
Seed production is cyclic, a year with high yields is followed by 2 - 3 years of light crops[
]. The tree flowers on new growth produced in spring, the seed ripening in its first year[
Quercus muhlenbergii brayi (Small.)Sarg., has somewhat larger seeds than the type, sometimes 3cm long[
Closely related to Quercus prinus[
]. Trees are often confused with Quercus prinus, Quercus prinoides and Quercus michauxii[
Trees respond well to coppicing[
Seedlings soon develop a taproot and become intolerant of root disturbance, they should be planted into their permanent positions whilst young[
Hybridizes freely with other members of the genus[
This species is threatened by fire, to a certain extent. Severe wildfire kills saplings and small pole-size trees but these re-sprout. Fire scars serve as entry points for decay-causing fungi, however, and the resulting decay can cause serious losses[
Plants in this genus are notably resistant to honey fungus[
Seed - cooked. The brown, oblong to ovoid seed can be 13 - 28mm long and 10 - 16mm wide[
]. The seed contains very little bitter tannin, it is quite sweet and rather pleasant eating[
]. Tastes nice when baked in an oven[
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.
An infusion of the bark has been used in the treatment of vomiting[
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 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 heartwood is dark brown, with a narrow band of paler sapwood. The wood is heavy, very hard, strong, close grained, durable. It weighs 53lb per cubic foot[
]. When properly dried and treated, glues well, machines very
well, and accepts a variety of finishes. A valuable wood for many uses, including making furniture, cabinet making and containers[
]. Not abundant enough to be used commercially, it is used for fencing, cooperage etc[
The heavy wood makes an excellent fuel, burning with 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.