Pedunculate Oak - Quercus robur
Irish name - Dair ghallda
Beech, Oak, Chestnut family - Fagaceae
Characteristics
- Pedunculate oak is a large slow-growing tree, reaching up to 30m (90ft), occasionally more at maturity. Oak can live for over 500 years, coppiced specimens may reach 1000 years.
- The leaves, with 4-5 usually unequal lobes on each side, are carried on very short leaf stalks.
- The male flowers are borne in slender catkins; the females in spiked stalks.
- Acorns are borne on long stalks or “peduncles”.
- The thick bark protects older oaks during fire; even young oaks will usually regenerate from the base.
Season
- Young leaves and flowers open mid-April to mid-May.
- The oak has a second flush of growth known traditionally as the Lammas growth since it tends to coincide with the Celtic Lammas Festival on August 1.
- The acorns ripen in October.
- Pedunculate oak tends to fruit abundantly only every few years. The crop is largely determined by the climatic conditions of the previous year at the time of bud burst.
- Leaves fall in late October and early November.
Preferred Environment
- Pedunculate oak generally occurs in the lowlands.
- This oak is found on heavy clays and loams, particularly where the soil is neutral or alkaline. It is a thirsty tree and needs plenty of water.
- It is not tolerant of salt-laden winds, thus is uncommom in maritime environments.
- The pedunculate oak is the dominant woodland tree on suitable soils and was very common throughout Ireland before being cleared for agriculture.
Wildlife Associations
- Approximately 284 identified insect species are associated with pedunculate oak.
- Pedunculate oak is considered beneficial to more species than most other native trees.
- In autumn, disc-like spangle-gall often covers the underside of the leaves.
Uses
- Oak timber has been used in Irish construction for 7,200 years.
- The tanning industry has historically used the bark in their processes.
Please remember...
Permission from the landowner - and, if the site holds any kind of designation, from Northern Ireland Environment Agency too - must be sought before collecting plant material (including seeds).


