Quercus ilex acorn bud (16/08/2011, Cambridge)
Position: Flourishes in full sun to partial shade.
Soil: Free draining soil.
Flowering period: Spring
Eventual Height: 25m
Eventual Spread: 20m
Hardiness: USDA Zone 7a-11
Family: Fagaceae
Quercus ilex is an medium sized evergreen tree eventually forming a bell shape. Its evergreen leaves are leathery, are dark green above and whitish below with dense short hairs on the underside. The leaf shape is variable and are 4cmm – 8cm long and 1cm – 3cm wide when mature. The leaves on the lower branches are often larger and spiny. Old leaves fall 1 – 2 years after new leaves emerge. Its bark is black and finely cracked. The tree produces yellow catkin flowers in spring followed by acorns which mature in about six months.
Commonly known as Holm Oak or Holly Oak, Q. ilex is native to the Mediterranean region of Europe. It takes its common name Holm from an Anglo-Saxon name for Holly. Q. ilex is not native to the UK and was introduced in the 1500s, it is now listed as an alien invader species and it is proposed that it should be included on Schedule 9 of the Wildlife and Countryside Act.
Quercus is the ancient Latin name for an oak tree but some authorities believe it to be derived from the Celtic quer meaning ‘fine’ and cuez meaning ‘a tree’. Ilex is from the Latin for holly referring to this trees juvenile leaves often being similar to that of Holly.
Quercus ilex (16/08/2011, Cambridge)
The Landscape architect may find this plant useful as an evergreen specimen tree which is tolerant of pollution. It may be used as an evergreen hedging species and is suitable for the maritime climate. This tree will not tolerate cold continental winters.
This plant will tolerate most soil conditions; it will be happy in acid, neutral or alkaline pH levels and will tolerate very alkali soils. I thrives in sandy, loamy or clay based soils and will even tolerate heavy clay soils.
The Royal Horticultural Society gave the tree Q. ilex their prestigious Award of Garden Merit in 1993.
Ecologically this tree is valuable to birds to provide shelter and nesting sites. The acorns also provide a source of food for a wide variety of animals. Q. ilex is one of the top trees for establishing a truffle orchard as the truffles grow in an ectomycorrhizal association with the tree’s roots.
Maintenance: Dead or damaged material may be removed in late autumn through winter. When maintaining this tree as a hedge it should be trimmed once a year in the winter months.
