Common names: Hazel 

Irish name: Coll 

Latin name: Corylus avellana 

Family: Betulaceae 

Origin: Native 

Tree type: Deciduous broadleaf tree

How it looks

Shape, bark, twigs 

Hazel is often coppiced, which encourages multiple stems to grow from ground level. If it is not coppiced, trees can reach a height of 12m. The light brown bark is smooth and shiny with yellow horizontal lines of ‘breathing pores’ known as lenticels.  

Buds 

The buds are 4-6 mm long, round, hairy, and alternate along the stem. 

Leaves 

The leaves are alternate along the stem. They are heavily toothed, heart-shaped, hairy and soft to the touch. The leaf has a characteristic point at the tip, growing around 10cm long.  

Flowers 

Hazel flowers in February before the leaves appear. Both male and female flowers are found on the same tree, a phenonmenon known as monoecious. The male flowers are on yellow catkins, which release pollen into the wind. Female flowers look like tiny red flowers on the end of a bud and are located on the branch above the male catkins. 

Fruits 

Once pollinated by wind, the female flowers develop into a cluster of one to four hazel nuts. The nut sits in a leafy cup known as a Cob. 

Similar species 

The introduced English Elm (Ulmus procera) has similar leaves to the hazel, though English elm leaves have rough hair, so they are not soft like the hazel leaves.

Where to find it

Hazel is widespread in Europe, North Africa, and western Asia. In Ireland, it thrives in lowland oak, ash, or birch woodlands, as well as in scrub and hedgerows. It can be found in limestone regions, like the Burren plateaus in north Clare and soil derived from limestone in the Glens of Antrim, often accompanied by diverse woodland flowers

Cultural importance

History | Myth | Literature

History 

Hazel has been a significant part of Irish culture since the first hunter-gather people populated the country and was used to make fish traps during the Mesolithic period (c. 8000-4000 BC). Archaeological evidence from over 6000 years ago suggests that hazel was one of the most popular firewoods during the Neolithic period (c. 4000-2500 BC). It was also used in the construction of wattle buildings and bog trackways throughout prehistory and into the Medieval (c. 400-1600 AD) period, and likely specially cultivated for this purpose. In fact, the remains of numerous hazel brush wood trackways dating to the Bronze and Iron Age have been identified in Irish bogs during archaeological survey and excavation. Large quantities of Hazelnut shells have also been recovered from archaeological excavations of prehistoric sites, indicating that hazelnuts formed a sizeable part of the diet of hunter-gatherer and early farming communities.  

In early Medieval Ireland (c. 400-1100 AD), the hazel tree was considered one of the seven ‘nobles of the wood’, cherished for its versatile contributions. As such, the early Irish law texts, stress that illegal damage to a hazel tree would incur a hefty fine. Hazel was an important source of firewood and building material during this period. Hazelnuts were also used to make hazel mead. Hazel was so significant in early Ireland, that the ‘C’ sound in the Ogham alphabet was represented by Irish name for the tree, ‘Coll’, and the associated Ogham character:

Hazel continued to be used to construct basic wattle and sod dwellings throughout the Medieval period and into the nineteenth century. However, Eoin Neeson notes that in the eighteenth-century people were banned from using hazel, amongst other similar woods, for these purposes, so that it could be exclusively used to provide fuel for the fast-growing iron and hemp industries. Whilst Paul McMahon explains that extensive land clearance for agriculture also took place at this time. Consequently, Hazel became less visible in the Irish landscape after 1700 AD.

Reference to hazel is commonly found in placenames throughout Ireland. For instance Drumcolliher or Drom Collchoille, in County Limerick translates as 'ridge of the hazelwood', while Barnacoyle or Bearna Choill in County Wicklow translates as, 'gap of the hazel'.

Myth, Legend and Folklore 

Hazel features frequently in Irish mythology. Hazel trees are often located near water, such as the nine hazels of wisdom which stood at the Well of Segais, at the source of either the Boyne or the Shannon river. Different versions of this story highlight the magical properties of hazel and that when the nuts fell into the well, they imbued it with knowledge and wisdom. However, if one ate the nuts or an animal who had eaten the nuts, as the hero Fionn Mac Cumhaill tasted the salmon of knowledge, they would be bestowed with wisdom. Hazel’s magical properties were also thought to include fertility, protection, inspiration and knowledge of poetry. In a similar connection, hazel is often used for water divining.

Literature 

Alongside mention in the Irish myths, hazel appears in early Irish poetry such as, ‘From Sinann I and II’, which describes the hazels of Segais and their supernatural properties. In his poem, ‘The Song of Wandering Aengus’, William Butler Yeats also writes about the magic of the hazel tree and its connection to the fairy realm. 

Value to wildlife

Nestled in the understorey of oak, ash, and birch woodlands, hazel trees enrich woodland habitats. Their leaves nourish moth caterpillars, and our red squirrels, jays, nuthatches, and many more forest animals enjoy their hazelnuts. 

Wildflowers flourish in managed woodlands where hazel is coppiced, supporting many butterflies, especially fritillary species. Coppiced woodlands are also good shelter for ground-nesting birds like nightjars, nightingales, and willow warblers. When hazel is left to mature, their trunks become homes to various mosses, liverworts, and lichens.

Threats

The species is not known to suffer any significant threat from pests or disease. However, coppiced hazel is susceptible to deer damage if not protected by fencing.

Uses

Coppicing hazel bushes encourages the production of multiple stems from one stump, which grows into slender, straight poles. These poles are perfect for constructing wattle and daub walls and sturdy fences. They were also integral to crafting eel and lobster traps.  

Most traditional charcoal production took place in hazel coppices. The wood makes some of the best quality charcoal, which is today used by artists as well as for burning.

References

Kelly, F. 1999. Trees in Early Ireland, Augustine Henry Memorial Lecture 11th March 1999, Irish forestry: Journal of the Society of Irish Foresters, 56, 39-57.  

Literature and Ireland’s Trees. 2023. Literature and Ireland’s Trees. Online: LIT: Literature and Ireland's Trees (litliteratureandirelandstrees.com) 

MacCoitir, N. 2015. Ireland’s Trees: Myths, Legends and Folklore. Cork: The Collins Press. 

McClatchie, M. 2014. Nuts about hazelnuts: the enduring tradition of foraging in Ireland, Ancient Food and Farming Blog. Online:Ancient Food and Farming: Nuts about hazelnuts: the enduring tradition of foraging in Ireland 

McClatchie, M. 2016. Nuts in Neolithic Ireland, Ancient Food and Farming Blog. Online: Ancient Food and Farming: Nuts in Neolithic Ireland 

McLoughlin, J. 2016. Trees and woodland names in Irish placenames, Irish Forestry, 73, 239-257.

McMahon, P. 2023. Island of Woods: How Ireland Lost Its Forests and How to Get Them Back, Dublin: New Island Books. 

McQuade, M. and O’Donnell, L. 2007. Late Mesolithic fish traps from the Liffey estuary, Dublin, Ireland, Antiquity, 81(313), 569–84. 

Moore, C. 2021. Between the Meadows: The archaeology of Edercloon on the N4 Dromod–Roosky Bypass: 11 (TII Heritage), Dublin: Transport Infrastructure Ireland. 

Neeson, E. 1991. A History of Irish Forestry, Dublin: The Lilliput Press Ltd. 

Raftery, B. 1996. Trackway Excavations in the Mountdillon Bogs, Co. Longford, Irish Archaeological Wetland Unit Transactions: Volume 3, Dublin: Crannóg Publishing. 

A-Z of British trees. Woodland Trust. Retrieved 11 April 2024, from https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/british-trees/a-z-of-british-trees/ 

Native Irish Trees. Tree Council. Retrieved 11 April 2024, from https://www.treecouncil.ie/native-irish-trees 

Stroh, P. A., Humphrey, T. A., Burkmar, R. J., Pescott, O. L., Roy, D. B., & Walker, K. J. (2023). BSBI Online Plant Atlas 2020. https://plantatlas2020.org/atlas