Belfast Botanic Gardens Tree Archive

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This is one of a series of short articles about trees in the Belfast Botanic Gardens compiled by the Friends group. The tree tag number relates to the small aluminium discs, usually fixed on the tree trunk, 2 to 3m above ground level.
Quercus petraea
Sessile oak

Tag 480
54 deg 34.956N
5 deg 55.932W

The Botanic Gardens has an excellent collection of oak species, both evergreen and deciduous. The sessile oak is one of the two oaks native to Ireland (the other is Quercus robur the pedunculate oak). Unfortunately the two species can hybridise so identification can be difficult. The oaks at the south end of the main field are Q. robur, having long stalks on the acorns and leaves with a very short leaf stalk. This tree, in the corner of the great lawn nearest Botanic Avenue is Quercus petraea. It has long petiols (leaf stalks) and short peduncles (acorn stalks). The leaves of Q. petraea also lack the little 'ears' (auricles) at the base of the leaf that are a characteristic of Q. robur. See comparative photo below.

Quercus petraea in Belfast Botanic Gardens

branch of Quercus petraea

Quercus petraea in Belfast Botanic Gardens

Branch of Quercus petraea

long petioles of Q. petraea

comparison of Q. robur and Q. petraea leaves

long petioles of Quercus petraea

comparison of leaves of Q. robur (left) and Q. petraea (right)

For information about Irish oaks see Flora Hibernica by JR Pilcher and VA Hall (Collins Press)

Photos taken in Belfast Botanic Gardens in 2007. Copyright: Friends of Belfast Botanic Gardens.

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