Horse Chestnut (Aesculus hippocastanum) Identification

Horse Chestnut / All year round / Toxic

The ‘nuts’ or ‘conkers’ of Horse Chestnut are a common and familiar sight in autumn, the tree was introduced to the UK from Turkey in the 16th century.

Common Names      

Horse Chestnut, Conker tree, Buckeye.

Botanical Name

Aesculus hippocastanum

Scientific Classification

Kingdom – Plantae

Order – Sapindales

Family – Sapindaceae

Physical Characteristics for Horse Chestnut


The leaves are palmate and have 5-7 pointed, crinkled leaflets. Each leaflet can be up to 30cm long. When the leaves fall they leave a distinctive horseshoe shaped scar on the branch.

\The original uploader was Andrikkos at Greek Wikipedia., Public domain, via Wikimedia Commons


The bark is thin when the tree is young, but it gradually grows thicker with age. As the tree matures the bark thickens into grey-brown flaky scales.


The flowers are white to yellow with a pink hue towards the base and they have 5 petals. They grow as an erect panicle that resembles a candle. Up to 50 flowers can grow on each panicle.

Karelj, Public domain, via Wikimedia Commons


Only around 5 fruits develop on each panicle, when young the cases are green but darken with age. Inside the cases are up to 3 of the ‘conkers’ which are a deep, rich brown with a whitish scar at the base. Up to 4cm across.

AnRo0002, CC0, via Wikimedia Commons


Mostly found planted in parks, roadsides and gardens.

Known Hazards

The seed contain significant amounts of a poison called esculin which can be deadly if consumed raw.

Could be Confused with…

It’s quite a distinctive tree and is well known by most people but don’t confuse it with Sweet Chestnut (Castanea sativa) Sweet Chestnut has sharper spines on the cases and the ‘nuts’ have a tassel or point.

Notes on Herbal Uses

The seeds contains a substance that thins the blood. It makes it harder for fluid to leak out of veins and capillaries, which can help prevent water retention. Extracts are also used to treat bruises and strains.

Extra notes from the Foragers

Apparently the Victorians made flour from conkers, they would shell and ground them before leeching out the tannins. It’s quite a laborious process and the resulting flour is still mildly poisonous.

Although we wouldn’t recommend them for the kitchen they can be used as an eco-soap. The nuts are extremely high in saponins and when crushed and soaked in boiling water produce a soap like product that you can used as a replacement for laundry detergent.


From the Woodland Trust

More on Herbal Aspects

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