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oak,any tree or shrub of the genus Quercus of the family Fagaceae (beechbeech,
common name for the Fagaceae, a family of trees and shrubs mainly of temperate and subtropical regions in the Northern Hemisphere. The principal genera—Castanea (chestnut and chinquapin), Fagus (beech), and Quercus
..... Click the link for more information. family). This complex genus includes as many as 600, found chiefly in north temperate zones and also in Polynesia. The more southerly species, ranging into the tropics, are usually evergreen. Oaks are cultivated for ornament and are prized as the major source of hardwood lumber. The wood is durable, tough, and attractively grained; it is especially valued in shipbuilding and construction and for flooring, furniture, railroad ties, barrels, tool handles, and veneer (particularly highly burled oak). The oaks are commonly divided into two groups, the black (or red) and the white. The former (e.g., the scarlet, pin, Spanish, willow, laurel, and shingle oaks) are characterized by leaves with sharp-tipped lobes and by acorns that mature in two years. The white oaks (e.g., the white, post, bur, cork, and holly oaks) are characterized by smooth-lobed leaves and acorns that mature in one year. Q. alba, the white oak, is the most important timber tree of the oak genus. Lumber-yielding species of chestnut (genus Castanea) are included in the white oak group when the term is used as a timber classification. The live oaks, evergreen species common in the S and SW United States, are sometimes considered a separate group. The bark of some oaks has been employed in medicine, in tanning, and for dyes; that of the cork oakcork oak,
name for an evergreen species of the oak genus (Quercus) of the family Fagaceae (beech family). The cork oak (Q. suber) is native to the Mediterranean region, where most of the world's commercial supply of cork is obtained.
..... Click the link for more information. supplies the cork of commerce. The gallsgall,
abnormal growth, or hypertrophy, of plant tissue produced by chemical or mechanical (e.g., the rubbing together of two branches) irritants or hormones. Chemical irritants are released by parasitic fungi, bacteria, nematode worms, gall insects, and mites.
..... Click the link for more information. caused by certain insects are utilized commercially. The Mediterranean kermes oak (Q. coccifera) is host to the kermes insect, source of the world's oldest dyestuff. Acorns, the fruit of oak trees, have long been employed as a source of hog feed, tannin (chiefly from valonia, the acorn cup of the Turkish oak, Q. aegilops), oil, and especially food. Acorns were one of the most important foods of the North American forest Native Americans; they were pulverized, leached to extract the bitter taste, and then cooked in various ways. Acorns have also been used as food in other regions where they are native. A symbol of strength, the oak has been revered for both historical and mythological associations. It was the favorite of Jove and Thor and especially sacred to the druids. St. Louis administered justice under an oak, and the Charter OakCharter Oak,
white oak tree that until 1856 stood in Hartford, Conn., and was thought to be 1,000 years old. There is a tradition that when Sir Edmund Andros, as governor-general of New England, demanded (1687) that the charter of Connecticut be surrendered by the colonists at
..... Click the link for more information. is legendary in America. Several unrelated plants are also called oak, e.g., the Jerusalem oak (a lobe-leaved annual of the goosefoot family) and the poison oak of the sumac family (see poison ivypoison ivy,
and poison sumac,
woody vines and trailing or erect shrubs of the family Anacardiaceae (sumac family), native to North America.
..... Click the link for more information. ). Oaks are classified in the division MagnoliophytaMagnoliophyta
, division of the plant kingdom consisting of those organisms commonly called the flowering plants, or angiosperms. The angiosperms have leaves, stems, and roots, and vascular, or conducting, tissue (xylem and phloem).
..... Click the link for more information. , class Magnoliopsida, order Fagales, family Fagaceae.
(Quercus), a genus of deciduous or evergreen trees; more rarely, shrubs of the family Fagaceae. The leaves are alternate, simple, feathered, lobed, or dentate, and sometimes entire. The flowers are small, opaque, unisexual, and monoecious. The stamens are on long, hanging catkins, and the pistils occur singly or in small bunches and are either sessile or on a peduncle. The fruit is a monospermous acorn that is often enclosed in a cuplike woody hull.
Oaks grow slowly, increasing in height for the first 80 years, and later, in circumference. They usually form a deep root system and send out numerous shoots from the stump. They need much light. Some species are quite drought-resistant and can endure severe winters and poor soil. Oaks begin to produce seeds at age 15-60 (earlier in open areas than in thickets). They reproduce chiefly by means of acorns. For planting, acorns gathered during the year of planting are used, since their ability to germinate quickly decreases. There are approximately 450 species of oak distributed in temperate, subtropical, and tropical zones of the northern hemisphere. In the USSR there are 20 wild species (according to other data, 11), which are found in the European USSR, the Far East, and the Caucasus, and there are 43 cultivated species.
In the Soviet Union the most important commercial oak is the pedunculate oak (Q. robur), which is 40-50 m high and 1-1.5 m in diameter. Its leaves are elongated and have an inverted egg shape, with five to seven pairs of short lobes, and they occur on petioles up to 1 cm long. The acorns occur singly or in bunches of up to three on peduncles. Beginning at age 40-60, the pedunculate oak flowers once a year, at the time of leaf formation. Fruit-bearing is abundant every four to eight years. With shade from the side, the tree grows quite rapidly, but it needs good overhead light. It lives 400-1,000 years. The pedunculate oak is found throughout the European USSR, in the Caucasus, and in most of Western Europe. In northern regions it grows chiefly in river valleys, but farther south it is found in watersheds and forms mixed forests with spruce. In southern regions there are oak groves. Oaks are found on the steppes in ravines and gullies. One of the basic varieties of timber in the broad-leaved forests of the USSR, the pedunculate oak is very similar to the sessile oak (Q. petraea), which has almost sessile acorns in bunches of two or three. The sessile oak is found in the western part of European Russia, the Crimea, and the northern Caucasus.
The Iberian oak (Q. iberica) is found in the eastern part of the northern Caucasus and in Transcaucasia. It has leathery leaves and sessile acorns that occur singly or in pairs. In the high mountains of the same region grows the Q. macranthera, which sends out thick shoots and has sessile acorns, which sometimes grow on short stems. The most common valley oak in eastern Transcaucasia is the long-stemmed oak (Q. longipes). An important timber variety in the Far East is the Mongolian oak (Q. mongolica), a frost- and drought-resistant tree.
The wood of the oak is very durable, hard, and longlasting, and it has a beautiful texture, with a pattern on the cross section. Because it does not rot, it is used to build ships and underwater installations. Oak is also used in railroad cars, furniture, cabinetry and coopery, and in house building. The bark of some varieties is used for cork (cork oak—Q. suber). The bark and wood contain tanning substances, which are used for tanning hides. The dried bark of young branches and slender trunks of Q. robur is used as a binder in an aqueous solution that is used as a rinse in treating inflammations of the mouth, pharynx, and larynx and as a moistener for treating burns. The acorns are processed into imitation coffee and feed for swine and certain other agricultural animals. Many species of oak, such as chestnut-leaved oak (Q. castaneifolia), are cultivated in gardens and parks as decorative plants.
REFERENCESFlora SSSR, vol. 5. Moscow-Leningrad, 1936.
Derev’ia i kustarniki SSSR, vol. 2. Moscow-Leningrad, 1951.
Menitskii, Iu. L. “Obzor roburoidnykh i gallifernykh dubov Kavkaza.” In Novosti sistematiki vysshikh rastenii. Leningrad, 1968.
Camus,A. Les Chênes: Monographie du genre Quercus, vols. 1-3. (Atlas.) Paris, 1934-48.
S. K. CHEREPANOV
What does it mean when you dream about an oak?
The sturdy and majestic oak tree represents stability, steadfastness, truth, tolerance, and wisdom. Psychologically, persons who identify with this symbol are seen to embody these qualities in their character. Commercially, the symbol of the oak tree is frequently used as a logo, implying strength and stability in business practices or civic pursuits.