Ajuntament de Barcelona

Quercus ilex

Hortes de Sant Bertran and Forestier's stairs

    Catalan name: 
    Alzina
    Spanish name: 
    Encina
    English name: 
    Evergreen oak
    Botanical synonyms: 
    Quercus gramuntia
    Observations: 

    According to the International Union for Conservation of Nature (IUCN), the conservation status of this plant is least concern.

    Species characteristics
    Family: 
    Fagaceae
    Origin: 
    Coastal Mediterranean area
    Habitat: 
    Forests in areas with more than 500 mm per year of rainfall
    Characteristics: 

    Perennial tree 8-15 m tall, with a crown measuring 8-10 m in diameter.

    The simple jagged leaf, 4-7 cm long, is bright dark green on the upper side and whitish green on the lower side. It resembles the holly leaf.

    The yellowish flowers are grouped into hanging catkins the masculine ones and solitary the feminine ones. 

    The fruits are small light brown acorns, 2-3 cm long.

    When young, it is often a shrubby that can be mistaken with the Kermes oak (Quercus coccifera); sometimes, because of the climatic or edaphic conditions of the place, it remains a shrubby.

    Flowering time: 
    April-May
    Fruiting time: 
    Early autumn
    Uses and properties: 

    Traditionally speaking, wood from Holly Oak is used as fuel, mainly as a resource for charcoal. Its hardness and resilience to decomposition make it very appreciated in carpentry to make furniture, garden tools, boats or cart wheels and in construction to make pilars and beams.

    Acorns are used to feed pigs and the sweet ones can be eaten by humans (either toasted, as a nut or to make flour). In some places in Extremadura, one can find Acorn Liqueur for human consumption.

    Some parts have been used in popular medicine.

    Tannins from the bark are used in tanning, hence its name, specially in Morocco. Because of its big life span, it's widely used in gardening as decoration, since it can be groomed almost at will, as seen in many places in Barcelona such as Dante Square or in the Greek Theatre (Teatre del Grec). Although used in urban environments, its sensitivity to plagues and sickness is higher when it grows in the wilderness.

    Growth of young samples is better in shadowed areas, although full sun exposure is not a problem when older.

    History and curiosities: 

    The scientific name of the evergreen oak, Quercus ilex, consists of the genus name Quercus, from the Celtic *quercuez, "oak, evergreen oak" —literally "beautiful tree", from *quer, "beautiful, elegant", and *cuez, "tree"—, and the Latin term ilex, "evergreen oak".

    The evergreen oak is one of the three main trees used to locate the truffle spots because of its symbiotic relation with the truffles.

    The evergreen oak, one of the indigenous trees of the Mediterranean forest, is the forest species that takes up most of the area in the Iberian Peninsula: approximately 3 million of hectares.

    For further information: 

    LÓPEZ GONZÁLEZ, Ginés A. Los árboles y arbustos de la Península Ibérica e Islas Baleares. (2 vol.) Madrid: Mundi-Prensa, 2001

    THE ROYAL HORTICULTURAL SOCIETY. Enciclopedia de plantas y flores. Barcelona: Grijalbo, 1996

    http://www.asturnatura.com

    http://www.rhs.org.uk