An oak is a tree or shrub in the genus Quercus of the beech family, Fagaceae. There are approximately 600 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably Lithocarpus, as well as in those of unrelated species such as Grevillea robusta and the Casuarinaceae (she-oaks). The genus Quercus is native to the Northern Hemisphere, and includes deciduous and evergreen species extending from cool temperate to tropical latitudes in the Americas, Asia, Europe, and North Africa. North America contains the largest number of oak species, with approximately 90 occurring in the United States, while Mexico has 160 species of which 109 are endemic. The second greatest center of oak diversity is China, which contains approximately 100 species.
Quercus kelloggii, the California black oak, also known as Kellogg oak, is an oak in the red oak section, native to western North America. Although genetically separated from them for more than 20 million years its leaves are remarkably similar in appearance to several other members of the red oak section including the red oak and the black oak found in eastern and central North America.
Cork is an impermeable buoyant material, the phellem layer of bark tissue that is harvested for commercial use primarily from Quercus suber, which is endemic to southwest Europe and northwest Africa. Cork is composed of suberin, a hydrophobic substance. Because of its impermeable, buoyant, elastic, and fire retardant properties, it is used in a variety of products, the most common of which is wine stoppers. The montado landscape of Portugal produces approximately half of cork harvested annually worldwide, with Corticeira Amorim being the leading company in the industry. Cork was examined microscopically by Robert Hooke, which led to his discovery and naming of the cell.
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines, and shrubs. Bark refers to all the tissues outside the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner bark, which in older stems is living tissue, includes the innermost area of the periderm. The outer bark in older stems includes the dead tissue on the surface of the stems, along with parts of the innermost periderm and all the tissues on the outer side of the periderm. The outer bark on trees which lies external to the last formed periderm is also called the rhytidome.
A lignotuber is a woody swelling of the root crown possessed by some plants as a protection against destruction of the plant stem, such as by fire. The crown contains buds from which new stems may sprout, as well as stores of starch that can support a period of growth in the absence of photosynthesis. The term "lignotuber" was coined in 1924 by Australian botanist Leslie R. Kerr.
Quercus ilex, the evergreen oak, holly oak or holm oak, is a large evergreen oak native to the Mediterranean region. It takes its name from holm, an ancient name for holly. It is a member of the Cerris section of the genus, with acorns that mature in a single summer.
Quercus cerris, the Turkey oak or Austrian oak, is an oak native to south-eastern Europe and Asia Minor. It is the type species of Quercus sect. Cerris, a section of the genus characterised by shoot buds surrounded by soft bristles, bristle-tipped leaf lobes, and acorns that usually mature in 18 months.
Quercus suber, commonly called the cork oak, is a medium-sized, evergreen oak tree in the section Quercus sect. Cerris. It is the primary source of cork for wine bottle stoppers and other uses, such as cork flooring and as the cores of cricket balls. It is native to southwest Europe and northwest Africa. In the Mediterranean basin the tree is an ancient species with fossil remnants dating back to the Tertiary period.
Quercus virginiana, also known as the Southern live oak, is an evergreen oak tree endemic to the Southeastern United States. Though many other species are loosely called live oak, the Southern live oak is particularly iconic of the Old South. Many very large and old specimens of live oak can be found today in the Deep South region of the United States.
Live oak or evergreen oak is any of a number of oaks in several different sections of the genus Quercus that share the characteristic of evergreen foliage. These oaks are not more closely related to each other than they are to other oaks.
Quercus agrifolia, the California live oak or coast live oak, is a highly variable, often shrubby evergreen oak tree, a type of live oak, native to the California Floristic Province. It grows west of the Sierra Nevada mountain range from Mendocino County, California, south to northern Baja California in Mexico. It is classified in the red oak section of oaks.
Quercus variabilis, the Chinese cork oak, is a species of oak in the section Quercus sect. Cerris, native to a wide area of eastern Asia in southern, central, and eastern China, Taiwan, Japan, and Korea.
Quercus faginea, the Portuguese oak or Valencian oak, is a species of oak native to the western Mediterranean region in the Iberian Peninsula and the Balearic Islands. Similar trees in the Atlas Mountains of northwest Africa are usually included in this species, or sometimes treated as a distinct species Quercus tlemcenensis. It occurs in mountains from sea level to 1900 m altitude, and flourishes in a variety of soils and climates.
The woodlands of the Iberian Peninsula are distinct ecosystems on the Iberian Peninsula. Although the various regions are each characterized by distinct vegetation, the borders between these regions are not clearly defined, and there are some similarities across the peninsula.
Los Alcornocales Natural Park is a natural park located in the south of Spain, in the autonomous community of Andalusia; it is shared between the provinces of Cádiz and Málaga. The natural park occupies a territory spanning seventeen municipalities with a total population of about 380,000. "Los Alcornocales" means "the cork oak groves".
The Mediterranean woodlands and forests is an ecoregion, of the Mediterranean forests, woodlands, and scrub biome, in the coastal plains, hills, and mountains bordering the Mediterranean Sea and Atlantic Ocean in North Africa.
The Iberian pig is a traditional breed of the domestic pig that is native to the Iberian Peninsula. The Iberian pig, whose origins can probably be traced back to the Neolithic, when animal domestication started, is currently found in herds clustered in the central and southern part of Portugal and Spain.
A dehesa is a multifunctional, agrosylvopastoral system and cultural landscape of southern and central Spain and southern Portugal; in Portugal, it is known as a montado. Its name comes from the Latin 'defensa', (fenced), referring to land that was fenced, and usually destined for pasture. Dehesas may be private or communal property. Used primarily for grazing, they produce a variety of products, including non-timber forest products such as wild game, mushrooms, honey, cork, and firewood. They are also used to raise the Spanish fighting bull and the Iberian pig. The main tree component is oaks, usually holm and cork. Other oaks, including melojo and quejigo, may be used to form dehesa, the species depending on geographical location and elevation. Dehesa is an anthropogenic system that provides not only a variety of foods, but also wildlife habitat for endangered species such as the Spanish imperial eagle.
Bot canker of oak is a disease on stems, branches and twigs of oak trees in Europe and North America. The casual agent of Bot canker of oak is the fungus Botryosphaeria corticola. Bot canker of oak causes lesions and cankers on a wide range of oaks in Europe and most recently live oaks in North America. Some infections were formerly attributed to Botryosphaeria stevensii, but most likely represent infections by Botryosphaeria corticola. Botryosphaeria corticola is distinguishable from Botryosphaeria stevensii via ITS rDNA sequencing.
The symbols of Portugal are official and unofficial flags, icons or cultural expressions that are emblematic, representative or otherwise characteristic of Portugal and of its culture.
