I’m sure we’ve all seen the Celtic Tree of Life, right? If you haven’t, here’s a picture…
Image from Mythologian
There isn’t a lot of historical context or information regarding what we see as the Celtic Tree of Life - only speculation about where it comes from and why it is important. However, in Irish Paganism, culture, and history, trees are extremely important.
According to Lora O’Brien, an Irish draoí and Priestess of The Morrígan, early Irish law was decided upon by the Gaelic Brehons. These were well-educated men and women of Old Irish society. It was originally an oral tradition, but the rulings were later written down by Christian Monks. You can find more information about the Brehon Law down below.
During the times of Brehon / Gael Law / Celtic Irish Law, there was no police force or prisons in Ireland. The Brehons (male and female) were arbitrators who remembered the laws in poems and had to be able to recite them when needed. A Brehon is not really a judge - its more like an arbitrator whose responsibilities included preservation and relevant interpretation of existing laws. Their status was displayed by the wearing of a torque around their necks. We are told in the old manuscripts that it would tighten chocking them if they told untruths and it would only loosen when the truth was told in place of falsehoods. Their interpretations were made public and could be challenged, so they had to stick to truth. This is very unlike the English Law system we suffer at present because today the ‘legal wigs’ stick only to the word of law as written and not to the intention of the wrongdoer. 
Image from Pixabay
Now you might be wondering what the heck any of that has to do with trees. Well, trees were so sacred to the Old Irish that they had laws regarding specific trees. These trees were also broken down into sub-sections based on the importance of the particular tree. If someone were to harm the tree in question, there would be payment required. The more important the tree, the higher the payment.
The 28 Principal Irish Trees
The categories of trees were broken down as follows, and these are considered to be the 28 principal Irish trees. 
The most valuable and noble are the airig fedo – ‘lords of the wood’.
- Dair ‘oak’ (Quercus robur, Quercus petraea)
- Coll ‘hazel’ (Corylus avellana)
- Cuilenn ‘holly’ (Ilex aquifolium)
- Ibar ‘yew’ (Taxus baccata)
- Uinnius ‘ash’ (Fraxinus excelsior)
- Ochtach ‘Scots pine’ (Pinus sylvestris)
- Aball ‘wild apple-tree’ (Malus pumila)
Then the aithig fhedo – ‘commoners of the wood’.
- Fern ‘alder’ (Alnus glutinosa)
- Sail ‘willow, sally’ (Salix caprea, Salix cinerea)
- Scé ‘whitethorn, hawthorn’ (Crataegus monogyna)
- Cáerthann ‘rowan, mountain ash’ (Sorbus aucuparia)
- Beithe ‘birch’ (Betula pubescens, Betula pendula)
- Lem ‘elm’ (Ulmus glabra)
- Idath ‘wild cherry’ (Prunus avium)
The fodla fedo are the ‘lower divisions of the wood’.
- Draigen ‘blackthorn’ (Prunus spinosa)
- Trom ‘elder’ (Sambucus nigra)
- Féorus ‘spindle-tree’ (Euonymus europaeus)
- Findcholl ‘whitebeam’ (Sorbus aria)
- Caithne ‘arbutus, strawberry tree’ (Arbutus unedo)
- Crithach ‘aspen’ (Populus tremula)
- Crann fir ‘juniper’ (Juniperus communis)
And least valuable are the losa fedo – ‘bushes of the wood’.
- Raith ‘bracken’ (Pteridium aquilinum)
- Rait ‘bog-myrtle’ (Myrica gale)
- Aitenn ‘furze, gorse, whin’ (Ulex europaeus, Ulex gallii)
- Dris ‘bramble’ (Rubus fruticosus aggregate)
- Fróech ‘heather’ (Calluna vulgaris, Erica cinerea)
- Gilcach ‘broom’ (Sarothamnus scoparius)
- Spín ‘wild rose’ (Rosa canina)
Again, it can only be speculated why these trees were considered sacred to the Old Irish community. Maybe they were sacred for their crop-producing ability like the Oak. Maybe there were sacred for their religious ability like the Juniper. We can’t know for sure, but what this goes to show us is how the Old Irish lived in connection with the land. This is something that I am trying to bring back into my own life and religious practice, and I think everyone can benefit from that same idea.
So, why is the Tree of Life significant?
It probably has something to do with the idea of all realms being connected - land, sea, and sky. The roots of the tree dig deep, and the branches of the tree reach tall. Trees are a representation of life around us and we can easily connect to them. They can offer healing, grounding, and energy to us. They can also offer us mundane things like shade, food, and structure. Whatever the case may be, the Tree of Life has a different significance for everyone.