Quercus petraea

Sessile Oak

Physical Traits & Growth

Typical max. heightiMaximum height in typical conditions, in metres. Full data also shows maximum achievable height in exceptional conditions.:
35m 1
40m 5
Usually up to 27m, rarely above 33m 6
39m 7

Max. canopy widthiLikely maximum horizontal width of the canopy, in metres:
Globular to broad ovoid crown, capable of very high canopy spread 1
At least 8m 2
Domed 3

Size of shadowiSize of shadow based on a fully grown tree, categorised as low, medium or high: High (490 sqm)

Canopy densityiShading intensity of the canopy when in full leaf. Categorised from open to dense.:
Moderately dense 1
Moderately high, more than Q. robur 3

Leaf emergenceiTime of leaf emergence, categorised as very early, early, late, or evergreen: Late (May to Nov 1)

Growth rateiHow quickly the tree grows during establishment. Categorised as low, moderate or high, with very high used in exceptional cases.: Low 3 to moderate 1

LongevityiExpected lifespan of the tree: Typically 400-500 years 8, potentially up to 600 to 1000+ years 2

Management & Systems

Typical systemsiCommon agroforestry or silvicultural systems where this species is used:
Arable or pasture 1
Well suited to upland conditions 1

Approach to silvicultureiCoppicing and pollarding ability:
Can be coppiced or pollarded 1
Good coppicing ability in south 3

Establishment requirementsiCommon requirements to establish the tree:
Slow-growing, may require aftercare for many years, including control of competitive vegetation and protection from herbivore pressure 3
Often needs formative pruning 6
Some grasses wil inhibit growth 6

Management requirementsiCommon long-term management needs such as pruning. Categorised as low, moderate or high.:
Minimal or no pruning 1
High pruning for good quality timber 23

Pruning timeiOptimal season for pruning: Spring (late) to summer 1

Pedunculate oak in Lustenau (Vorarlberg, Austria)/ Asurnipal/ https://creativecommons.org/licenses/by-sa/4.0/deed.en

Products & Economy

Food productsiCommon food products such as fruits and nuts: –

Wood productsiCommon wood products, including timber, turnery, and pulp:
High value timber 123, including sawnwood, veneers, plywood 5
Max YC 8 4, average 3-5 2
Timber is very prone to defects e.g. epicormic growth 2

BiomassiCommon biomass products such as fuelwood: Fuelwood 35

Speciality productsiOther speciality and niche products: Acorn flour 1, various medicinal products 5

Time until market (food)iNumber of years until the tree produces food products: –

Time until market (timber)iNumber of years until the tree produces wood products:
Rotations for sawn wood or veneer tend to be longer than robur, 120 years or more 6, up to 160 years 8
15-25 year coppice rotation 11

Ecology & Utility

Nutrient and organic matter accumulationiRough estimate of soil-improving properties, with larger and deeper-rooting trees predicted to have higher value. Categorised as low, moderate or high.: High – deep roots and large canopy area

Nitrogen fixationiNitrogen-fixing properties, categorised as yes or no: No

High carbon sequestrationiAll trees sequester carbon, but faster-growing, larger trees generally have higher sequestration potential.:
Short-term (20 years): Moderate
Medium-term (40 years): Moderate
Long-term (60 years): Low

Native status in the UKiCategorised as native, long-established, or recent introduction.: Native 1

High wildlife valueiMost trees are likely to be of some value to wildlife, but some trees are of generally higher value to various wildlife groups:
Very high 5
Highest value for mycorrhizal fungi, wood-decay fungi and invertebrates, foliage invertebrates, seeds, and epiphyte communities 5

Pollinators

Flowering period (pollinator benefit)iTypical flowering months: Apr-May 1

High pollen and nectar value for pollinatorsiValue of flowers to pollinators: Low 1

Susceptibility & Risks

Risk of toxicity to livestockiReported potential toxicity to livestock, categorised as yes or no. Toxicity is complex and often context-specific.: Risk of toxicity from buds, young leaves and acorns, especially in cattle and horses 1731

Risks to farming operationsiOther risks such as suckering roots, very large tree size, secondary host for aphids, and flammability:
Capable of becoming very large spreading tree 2
Can support Oak Processionary Moth, which has human health risks 6

Disease susceptibilityiSusceptibility of the tree (not tree products) to diseases, e.g. fungal and bacterial disease:
High
Main risks are powdery mildew and other fungi, and acute oak decline 5
Acute oak decline potentially higher risk in droughts 5
Risk of acute oak decline and chronic oak decline 3
May be susceptible to powdery mildews and honey fungus 6

Invertebrate pest susceptibilityiSusceptibility of the tree (not tree products) to invertebrate pests, e.g. aphids and other insects:
Moderate
Susceptible to oak processionary moth 35
May be susceptible to aphids, caterpillars, leaf-mining moths, oak gall wasps 6

Vertebrate damage susceptibilityiSusceptibility of the tree (not tree products) to vertebrate pests, e.g. squirrels and deer:
High
Moderate sensitivity to browsing 7, moderately high palatability 8
Highly susceptible to grey squirrel damage, not worth growing for timber where population is high 5