Pedunculate oak (Quercus robur): what the forestry bodies record

This page reports what forestry bodies say about one tree. It does not identify trees from descriptions or photos and does not say what should be done with any tree. Each fact names its source, all read on October 9, 2026. The pests and diseases of oak that this site profiles are gathered in what attacks oak.

At a glance

Item	What the source records
Scientific name and family	Quercus robur, family Fagaceae (Woodland Trust)
Common names	English oak, pedunculate oak and common oak (Woodland Trust); Forest Research files it as Pedunculate oak with the code POK
Origin	Native (Forest Research and Woodland Trust)
Height	Up to 20 to 40 m, with a broad, spreading crown (Woodland Trust)
Rainfall and exposure	More than 600 mm of rain preferred; moderate exposure (Forest Research key properties)

Range

Forest Research says pedunculate oak is native to the British Isles except the far north, and to much of Europe. It names pedunculate and sessile oak as the two native oaks of Britain, with pedunculate dominant in the south, east and centre of England and sessile prominent in the west of England, Wales, Scotland and Ireland. It records a recognised hybrid of the two, Quercus x rosacea, widely distributed in Britain, with features of both parents that can make identification difficult. EUFORGEN, the European forest genetic resources programme, calls the tree large, long-lived and deciduous, native to Europe and parts of western Asia, and found in lowland forests and mixed woodlands, often forming dominant stands. The Woodland Trust calls it a very common tree, found most often in deciduous woods across southern and central Britain.

Site and soil

Forest Research says pedunculate oak is more light demanding than sessile oak, wind-firm and cold hardy, but open to damage from late spring frost when young. It says the tree can tolerate some exposure, though form is likely to be poor. It describes soils of medium to rich nutrient status, a preference for heavy, moist soils with a pH between 4.5 and 7, and tolerance of some waterlogging provided the soil does not dry out in summer. The entry says very free-draining soils with a fluctuating water table can lead to ring shake, a defect in the timber. It adds that the tree roots deeply, lacks apical dominance and tends to a bushy shape if open grown. EUFORGEN says the tree can grow in highly diverse conditions but prefers fertile and well-watered soils, and acts as a pioneer species on plains and hills, but as a late successional species in valleys and floodplains.

Leaves, flowers and acorns

The Woodland Trust describes leaves about 10 cm long with four or five deep, smooth-edged lobes, almost no leaf stalk, and growth in bunches, with leaf-burst in mid-May. Flowers are long, yellow hanging catkins. Acorns are 2 to 2.5 cm long on long stalks, which gives the species its name pedunculate. In winter it names rounded buds in clusters, each with more than three scales, as the way to identify it. For sessile oak the page says the reverse holds: leaf stalks and no acorn stalks.

Wildlife and timber

The Woodland Trust says oak in the United Kingdom can support more than 2,300 species, more biodiversity than any other native tree, though not on a single tree. Forest Research says both native oaks host many thousand species of native flora and fauna. For timber, the Woodland Trust calls oak one of the hardest and most durable on the planet and says it takes up to 150 years before an oak is ready for construction. EUFORGEN says the wood is valued for construction, shipbuilding, furniture, veneer, fencing and firewood, and that a high tannin content makes it resistant to insect and fungal attacks and useful for wine and spirit barrels.

Pests and diseases the sources name

Forest Research says pedunculate and sessile oak are relatively free of pests and diseases. It records oak mildew, a fungus that coats young leaves in white powder in warm humid conditions and is not thought to have a lasting effect, and defoliation from gypsy moth (also called spongy moth), oak leaf roller moth and winter moth that it says generally causes no long-term health problems. It says knopper gall often deforms and aborts acorns, and that grey squirrels can cause occasional, sometimes acute damage.

Two entries are reportable through TreeAlert, as the same entry states. Oak processionary moth is called a notifiable defoliator that Forest Research considers primarily a threat to human health rather than tree health. Acute oak decline is called an emerging disease, usually of mature oaks, seen as weeping patches or stem bleeds and often with the D-shaped exit holes of the two-spotted oak buprestid beetle. The Woodland Trust says decline of mature oaks first aroused concern in the 1920s, and that most cases are in central, southern and eastern England.

Text on Forest Research is adapted from its tree species database entry and contains public sector information licensed under the Open Government Licence v3.0.