The oaks or oaks (genus Quercus) They are shrubs and timber trees that can reach 45 m in height and belong to the Fagaceae family. This genus includes more than 300 species of plants distributed in the temperate mountainous regions of the northern hemisphere between the parallels 15º-30º N.
They are characterized by their erect trunks with dark-colored cracked and fissured bark and dense green or reddish-brown foliage. It constitutes one of the genres most used by man as a source of high quality tannins, carbon and wood, durability and resistance.
Most species of the genus Quercus they have been subjected in their diverse natural environments to intense deforestation. Either because of their high commercial value as timber species or simply because of the expansion of agricultural frontiers and livestock operations..
In addition, the oaks and the common oak have suffered huge losses caused by forest fires and mining operations. In this regard, many of the repopulations are carried out with fast-growing species such as pines or eucalyptus, thus losing their natural spaces..
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Species belonging to the genus Quercus They are frequently large shrubs or trees with straight and leafy trunks. Simple, alternate and stipulate leaves, with deciduous, evergreen or marcescent habits, and with entire or serrated margins.
The male flowers appear in hanging racemose inflorescences, each flower contains 4-10 stamens and long filaments. The female flowers in spikes or heads have three stigmas and anthropic ovules surrounded by a compact structure that will be the capsule when they mature..
Its fruit is a nut or acorn in an axial position, individually or in groups of two or three units. It is surrounded by a leathery capsule, with a large seed devoid of endosperm and bulging and succulent cotyledons..
- Kingdom: Plantae
- Division: Magnoliophyta
- Class Magnoliopsida
- Order: Fagales
- Family: Fagaceae
- Gender: Quercus
The oak or oak forests are located throughout Europe and Asia, through the Middle East, northeast Africa and America. In fact, they are found in most of the temperate forests of the Northern Hemisphere, even in some tropical and subtropical regions..
Sowing is done during the fall with freshly collected seeds from vigorous acorns and free of bruises, pests or diseases. In spring, stratified seeds can be used in a percentage mixture of sand and peat, maintaining humidity for 30-60 days at a temperature of 0-2º C.
In the case of using stratified seeds, there is a small root of 2 - 5 cm that it is recommended to prune before sowing. The culture is established in polyethylene bags of 500 cc in volume with a loose substrate rich in organic matter..
Germination occurs between 4-6 weeks after sowing. Trying to maintain adequate agronomic practices during the seedling growth process: irrigation, weeding, fertilization, pest and disease control.
The plants will be ready to be transplanted to the final site when they reach an average height of 25-40 cm.
The stored seeds are regularly attacked by small beetles of the Curculionidae family. The damage is caused by larvae that penetrate the seeds and develop inside them. When maturing the adult emerges, making the perforation evident.
During the establishment in the nursery the seedlings are affected by the fungus Pestalotia sp., causal agent of leaf spot. The symptoms are manifested with yellowing of the leaves, necrosis and death of the plant.
In plants planted in the field, the disease called descending death of oak has been detected, caused by the fungus Ceratocystis fagacearum associated with coleoptera Xyloborus sp. The plant experiences loss of vigor, defoliation and reduction of the foliage causing the downward death that ends with the death of the tree.
Acorn of various species is consumed by man or used as food for wild animals or cattle and goats. In the Iberian Peninsula, the fruits are destined for feeding the Iberian pigs used in the production of Serrano ham..
The fruits of some species of oaks such as the Quercus ilex Y Quercus alba They are used by hand to make flour. This process consists of roasting, cooking, leaching and adding additives such as bicarbonate or clays to eliminate the astringent flavor of the acorns..
Species like Quercus tinctoria Y Quercus coccifera contain chemical elements similar to mealybug. Thus, this characteristic makes them useful to be used in the dyeing and coloring industry..
In addition, the bark of various species of Quercus It contains a large percentage of tannins, an astringent substance used for the tannery industry. The crust of the Quercus suber - Mediterranean cork oak - used to make corks for wine and cognac bottles.
The wood of the Quercus It is highly appreciated for its firmness, weight and durability, being used for the manufacture of ships, constructions, furniture, carpentry and joinery in general. It is currently used for the manufacture of wooden barrels where wine and cognac are aged during their fermentation process..
The medicinal properties of Quercus They are the result of the amount of flavonoids and tannins it has, which provide anti-inflammatory, antiseptic, astringent and hemostatic properties..
The artisanal use of decoctions or infusions of leaves and bark is used satisfactorily for the treatment of digestive complaints. In fact, it is effective in relieving diarrhea, intestinal bleeding, gastritis, urinary incontinence, rectal problems and pharyngitis..
In addition, it is recommended to treat gum problems, nosebleeds, mouth sores, skin conditions and angina.
Robust tree species up to 30 m in height known as Andalusian gall or Andalusian oak. Under natural conditions, it has a wide and dense crown with a trasovado profile that projects a large rounded or irregular shadow..
Native to southwest Europe and North Africa - Morocco -, on the Iberian Peninsula it is located in Andalusia, Algarve, Catalonia, Sierra Morena and Toledo. It grows in medium mountain areas, ravines, slopes and stream banks at altitude levels below 1,000 meters above sea level. .
A shrubby species that under favorable conditions can reach 5 - 6 m in height, it is a phagaceae native to the Mediterranean region. It is commonly known as carrasco, holm oak, carrasquilla, carrasquizo, kermes oak, chaparra or chaparro.
It is a very resistant plant to dry and arid climates around the Mediterranean, being tolerant to extreme temperatures and low rainfall. The wood is used as firewood to obtain charcoal, and the acorns are used as food for goat and pig herds.
Marcescent tree with a wide crown and dense foliage that reaches 20 m in height, typical of North Africa and the Iberian Peninsula. Its leaves are characterized by remaining on the tree during autumn until the following spring when the first flower buds emerge..
It is known as Carrasqueño oak, Quejigo or Valencian oak, it grows in all types of soils and seasonal variations, growing up to altitude levels of 1,900 meters above sea level. Its wood is used for the manufacture of agricultural or artisanal tools and in the construction of storage containers or barrels..
Evergreen tree native to the Mediterranean region of medium - low size, 20 - 25 m high with a leafy and spreading crown. This type of holm oak is known as holm oak, chaparro or chaparra, it has a very cracked and rough bark that is gray - brownish in the case of older trees..
It is distributed in a large part of the Iberian Peninsula and the Balearic Islands, forming dense forests associated with scrub and climbing plants. The species is of great landscape importance, forming part of the holm oak forests - meadows - linked to rural development. It is a source of charcoal and is used in tannery.
Large deciduous species. Large and imposing tree, it reaches 45 m in height, presenting an open and extensive crown, and a strong root system. Known as winter oak or sessile oak it is part of the white oaks of North America, Europe and Asia.
It grows and develops along the mountainous slopes, on dry and deep soils, even in rocky terrain up to 1,800 meters above sea level. The wood is highly appreciated for its hardness and quality, its acorns are used as a nutritional supplement and it is a source of tannins for tanning hides..
The downy oak is a deciduous species up to 20 m high with an extended crown and dense foliage, characterized by its very hairy young branches. It is distributed in the lower part of Europe, from Spain to the Asian border of Turkey, between 400 - 1,500 meters above sea level..
It adapts to warmer and drier climates than other oak species, preferably on limestone soils, with low fertility and little weathering. It is a species used for agroforestry purposes, the wood is used as firewood for combustion and contains tannins used in tanneries..
Deciduous tree species 25 m high, more rustic and open than other oak species, commonly known as melojo or rebollo. During the summer the foliage has a light green color that turns brown and marcescent during the winter..
It is distributed in the western Mediterranean, the Iberian Peninsula, southern France, North Africa, including Morocco and the Rif massif. At medium sun exposure, between 500-2000 meters above sea level and average annual rainfall of 650-1,200 mm. The wood is used in construction and carpentry, with extensive agroforestry use.
The common oak, ash oak, box or horse oak is a large, robust and majestic species that can reach 40 m in height. It is a deciduous tree with a woody stem with wide longitudinal cracks and an extended crown..
It inhabits throughout Europe and Western Asia, even in extreme climatic conditions from sea level to 1,400 meters above sea level. It is used as an ornamental tree and its wood is of excellent quality, hard, heavy and resistant, widely used in joinery and carpentry..
A deciduous tree species with large leaves that can reach 25 m in height, it is characterized by its gray and soft bark. Called American Red Oak, Northern Red Oak, or American Red Boreal Oak, it is native to east-central North America.
In Europe it is cultivated as an ornamental or for forestry purposes; however, in some areas it is considered an invasive species. It is cultivated commercially for the quality of its wood, and as an ornamental species due to its graceful appearance and attractive foliage during the fall..
Small evergreen tree, relatively short stem and rounded crown that does not reach 15 m in height. Native to North Africa and Europe, it has been widely spread due to the excellent cork obtained from its bark.
It is known as cork oak, being a very common tree in Mediterranean forests with high annual rainfall and temporary dry periods on siliceous soils. The use of cork is its main economic value. However, firewood and charcoal are of excellent quality and their acorns are a source of animal food..
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