The sessile oak (Quercus petraea) is part of the fagaceum family of flowering plants that also includes beeches and chestnuts. You may also know the sessile oak as the Cornish, Irish or durmast oak, as it is the official tree of Ireland and an unofficial emblem in Wales and Cornwall. You can find the sessile throughout most of Western Europe, including in many EcoTree forests.
The sessile oak is a deciduous tree important both ecologically and economically, as it is traditionally used for building materials. It also grows well in sandy soils and at higher altitudes up to 1600 metres. Providing shelter to many animals, the sessile oak plays a key role in biodiversity too.
A sessile oak can live for 500–1000 years and reach up to 45 metres high with a trunk 2 metres in diameter. Its bark has vertical ridges with continuous grooves that allow rainwater to make its way to the ground. Up high, the sessile oak has a full crown with shallow-lobed leaves that easily detach from their petioles or stalks.
It is a monoecious species, with male flowers in long catkins at the base of the leaf blades, and small female flowers found in clusters. The sessile – which means stalkless – produces acorns attached directly to the twig.
A sessile oak prefers oceanic, humid climates and fine sandy lime soils, especially if they are slightly acidic. It needs a regular water supply but can stand short spells of drought. However, it does not do well in deep frosts, especially later in the year when the cold tends to destroy its flowers.
We usually plant sessile oaks in autumn when we know there is no frost forecast. It’s important to plant them in a ditch 3 to 4 times larger than and just as deep as their clump of roots. In its first year after planting, a sessile oak should be watered regularly, especially if it is already tall.
Sessile oaks produce high quality wood that is both very solid and easy to work with. Traditionally, the sessile has been used for building materials, ships and making furniture.
The sessile oak has come to symbolise strength, power and generosity. With such a long lifespan, it’s been an ever present in most of our lives, which is why it makes the perfect sustainable birthday gift. What better way to celebrate a relationship that lasts than with a unique gift and living memory of such a happy occasion?