Common names: Horse chestnut 

Irish name: Crann cnó capaill 

Latin name: Aesculus hippocastanum  

Family: Sapindaceae 

Origin: Native to the Balkans

Tree type: Deciduous broadleaf tree

How it looks

Shape, bark, twigs 

It is a large deciduous tree with a huge domed crown. All its parts are distinctive making it an easy tree to identify. Horse chestnuts can live up to 300 years. The bark starts smooth and pinkish grey in young specimens, but is greyish brown in mature trees and develops scaly plates.

Buds 

They have large thick, sticky buds up to 3.5cm which are easily recognisable in the winter months. 

Leaves 

The leaves known as palmate in shape, resemble a human hand.  With 5-7 leaflets, they are considered large and can be up to 25cm long. The upper surface of the leaf is smooth with the underside of the leaf being slightly hairy / downy.

Flowers 

Large, upright, white or pinkish flowers resembling candelabras appear all over the tree in May. These are quite fragrant and very popular with pollinators. 

Fruits 

The fruits of the tree appear as green spikey cases or shells which are home to a brown shiny seed known as a conker.

Where to find it

It is native to the mountains of the Balkans. It grows very well in Ireland's temperate climate. It is a very popular landscape tree so can be found in many estates and parklands throughout the country. It can also be found in many European cities due to its popularity amongst gardeners and planners during the 19th century.

Cultural importance

History | Myth | Literature

History 

Native to the Balkans, the horse chestnut was introduced to England from Turkey in the sixteenth century and then from there to Ireland in early 1600s. It has been planted in Ireland as an ornamental tree for over 200 years and can be seen on landed estates throughout the country. Loved by planners and designers, it quickly became established in many European cities during the nineteenth century.  

As horse chestnut is a soft wood, its timber has little commercial value. Although, it has been suggested that it was used in the past for woodcarving and to make dairy maid's buckets. The conkers of the horse chestnut are probably best known for their use in the game of the same name, ‘Conkers’, which children have been playing since at least the mid-nineteenth century. However, they were also used to make medicine for both humans and animals. Indeed, as they were traditionally used to make medicine for horses, it is thought that this is where the name ‘horse chestnut’ comes from. In England during the Second World War, conkers were ground to make a coffee substitute and to make a type of starch that was necessary for the production of the explosive cordite. In addition, the flower buds of the horse chestnut were sometimes used instead of hops to make beer. 

The horse chestnut is special to the people of Kyiv in Ukraine, so much so that the blooming horse chestnut was once the official symbol of the city. It is known as the ‘City of Chestnuts’ as horse chestnuts are abundant throughout its many squares. Other famous horse chestnuts include the avenue of trees planted at Bushy Park in the Borough of London by Christopher Wren in 1699 and the horse chestnut that Anne Frank could see from her attic window in Amsterdam while she was in hiding, and which she frequently wrote about as a symbol of freedom. Saplings of the tree were donated as part of the Anne Frank House seedling project to various schools and organisations throughout the world before the parent tree fell in 2010.

Myth, Legend and Folklore 

Although there appears to be little folklore or mythology surrounding the horse chestnut, it has been suggested that in Europe, it is seen as a symbol of luck, prosperity, protection and strength.

Literature 

The horse chestnut features in the Ukrainian song ‘Kyiv Waltz’, written by Andrei Malyshko and Platon Mayboroda, which is considered an anthem of the capital: 

Again chestnuts bloom, 
Dnieper Wave beats. 
Youth dear - 
You are my happiness. 

Value to wildlife

Its flowers are very popular with nectar loving insects such as bees. The triangle moth caterpillar feeds on the leaves of the Horse Chestnuts, as do the caterpillars of the horse chestnut leaf-miner moth, which are in turn food for blue tits. Deer and other mammals eat the conkers. 

Threats

Horse chestnuts are known to suffer from fungal diseases. The trees can also be affected by a bacteria called bleeding canker, this affects trees of all ages and can eventually cause death of the tree. 
 
The horse chestnut leaf miner is a small moth with caterpillars that can occur on trees in huge numbers, causing the foliage to turn brown and fall early by feeding on the inside of the leaves. As most of the damage occurs late in the season there is little evidence to suggest that this harms the tree, but it does affect its appearance. 

Uses

Its soft timber has no economic value so it is grown mostly for its ornamental properties. In herbal medicine, an extract from the fruit is used to treat vascular disorders in humans. 

References

Anne Frank House. 2024. The Chestnut Tree, Anne Frank House Website. The chestnut tree | Anne Frank House

Don, M. 2005. The Oldest Swinger, The Guardian, October 23 2005.  The oldest swinger | Life and style | The Guardian

Fota Wildlife Park. 2024. Horse Chestnut, Fota Wildlife Park. Horse Chestnut - Fota Wildlife Park

Keegan, B. 2023. Plants, Identity, and War in Ukraine, The Arnold Arboretum of Harvard University. Plants, Identity, and War in Ukraine - Arnold Arboretum | Arnold Arboretum (harvard.edu)

Lack, H.W., 2002. The discovery and rediscovery of the horse chestnut. Arnoldia, 61(4), pp.15-19.

McMahon, P. 2023. Island of Woods: House Ireland Lost its Forests and House to Get them Back. Dublin: New Island

Rankel, K. 2024. 10 Advantages of Having a Horse Chestnut, Greg App Website. 10 Advantages of Having a Horse Chestnut (greg.app)

Singleton, A. 2019. Curious Conkers - Unravelling the bonkers conkers myths, Wildlife Trust for Lancashire, Manchester and North Merseyside. Curious Conkers - Unravelling the bonkers conkers myths | Brockholes Nature Reserve

Vdovenko, N. 2008. Chestnut - Blooming symbol of Kyiv, National Technical University of Ukraine. Chestnut - Blooming symbol of Kyiv | Igor Sikorsky Kyiv Polytechnic Institute (kpi.ua)