First reported in the wild
Invasive species - risk of Medium Impact
Occasionally present, casual, vagrant, migratory
Introduction pathways - 1
Release in Nature
Introduction pathways subclass - 1
NAPRA Ireland risk assessed
Deciduous oak tree up to 40m tall; leaves 9-12cm long, dark green with 4-9 lobes; acorn cup covered in long scales and covering half the acorn (Booy et al., 2015).
Impacts of Quercus cerris invasion are associated with the subsequent introduction and survival of three oak gall wasps (Andricus corruptrix, A. kollari and A. lignicola), which alternate on native oak trees damaging them (Walker et al., 2002), though it may replace native vegetation if spread mirrors that of in Britain (Preston et al., 2004).
Woodland, forest and other wooded land; Constructed, industrial or other artificial habitats
Pathway and vector description
Widely planted as an ornamental tree in woodlands, parks, roadsides and gardens (Preston et al., 2004). Thought to rarely self sow in Ireland with only 4 reports of seedlings (Reynolds, 2002), it is thought to have undergone a rapid expansion in range in Britain since the 1960s despite being present in the wild since 1905 (Preston et al., 2004), it is unknown if a similar pattern is occurring here. Widely sold in garden centres.
Mechanism of impact
Competition, Disease transmission
Found in parks, woodlands, gardens, roadsides and old estates (Preston et al., 2004; Reynolds, 2002).
Europe, Temperate Asia
Quercus ilex, Quercus rubra
Occasional - Widespread - Rarely established, occasionally self sown (Reynolds, 2002). Distribution may be an artefact of recording effort.
Native to southern Europe and south west Asia, though naturalised in much of Europe (Preston et al., 2004).
Date of first record category
Fifty year date category
Records submitted to Data Centre in 2020
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How can you help
Report any sightings to the National Biodiversity Data Centre.
Reynolds, S.C.P. (2002) A catalogue of alien plants in Ireland. National Botanic Gardens. Glasnevin, Dublin. Preston, C.D., Pearman, D. A. & Dines, T. D. (2002). New atlas of the British and Irish flora. An atlas of the vascular plants of Britain, Ireland, the Isle of Man and the Channel Islands, Oxford University Press. Booy, O., Wade, M. & Roy, H. (2015) A Field Guide to Invasive Plants & Animals in Britain. Bloomsbury. Walker, P., Leather, S. R., & Crawley, M. J. (2002). Differential rates of invasion in three related alien oak gall wasps (Cynipidae: Hymenoptera). Diversity and Distributions, 8(6), 335-349.