Foodways and Climate Change in Ancient Ireland

A history of a landscape

If you didn’t know, Ireland is an island. Because of this, and its location far north, it was one of the later land masses to be inhabited by humans. The early Holocene, that is, about 100,000 years ago, saw the establishment and expansion of woodland as the dominant habitat on the island of Ireland. 

When humans arrived, the landscape drastically changed. There is very little evidence of mammalian fauna before humans; especially large mammals. ¹ Even species thought to be ubiquitous to Ireland such as red deer and aurochs seem to have been absent in the early Holocene and are only documented during the Neolithic.

The introduction of boar, dog, and possibly bear to Ireland likely includes moving animals as animals for subsistence, as companions, and as animals of likely symbolic interest.  Essentially, they were engineering their ecologies to enhance specific niches, but we don’t fully understand the relationships that linked humans and animals. 

Food procurement in Mesolithic Ireland was heavily focused on the gathering of plants, including seeds and fruits, roots, leaves, and stems. Plants were gathered not just for food, but also for the manufacture of clothing, tools, and structures, as well as the production of medicines and perhaps the consumption of hallucinogens. So, we don’t *really* know for sure, but there’s a long history of the use of mushrooms, most specifically psilocybin, and amanita muscaria, but there are at least eight different varieties that are native to the island.² There is a long history of prehistoric rock art swirls in Ireland, and given the design style, it’s not hard to assume that the artists were heavily under the influence of hallucinogens.

There’s also a longstanding theory, and this is going fast forward a bit, that magic mushrooms were used in religious ceremonies before Christianity came knocking. Things like fly-agaric fungus, which is the red mushrooms with white dots all over it, was prepared for consumption because it gave its users great knowledge and enlightenment. 

Fly-Agaric Fungus. Less fly than expected.

Now, these wooded landscapes, unsurprisingly, weren’t significantly different from most of the UK. There’s a boatload of evidence of hazelnut shells being burnt in controlled fires, just like we see in the rest of this region of Europe. Archaeologists have found caches of hazelnuts at several sites. The storing of plant foods is often considered to be associated with agricultural societies but was also practiced by hunter-gatherers in Mesolithic Europe and North America.³

Not only is there extensive evidence of hazels being stored and eaten, but cooking sites were discovered that also had charred remains of pears & apples, crowberry, raspberry, and waterlogged remains of brambles, probably for basket-making, and guelder-rose. Now, guelder-rose berries are inedible unless they’re cooked or made into wine, but raw, they have a long history of being used as an herbal remedy that causes cramping. While many of these fruits are autumn ripening, it should be noted that crowberries can remain on the plant through the winter, thereby extending the harvesting period. With the possible exception of crowberry, these fruit-bearing plants are associated mainly with woodland margins, further emphasising the importance of wooded landscapes & the management of the forest in Mesolithic food procurement strategies.

Crowberries.

Beyond fruit, the Irish also have a long history of eating tubers, just not the ones you’re thinking that I’m talking about. Charred tubers of Lesser Celandine and species in the Sedge family have also been documented, all of which had inhabited the forest floor.  And those aren’t the only ones that existed either in forests or on forest edges. Cleavers, a small annual plant, as well as bedstraws, both of which typically inhabit forest edges, have been extensively documented from cooking sites. Cleavers were also the second most common charred plant other than fruit and nut remains at many of the sites, which is interesting because that would suggest extensive amounts of forest margins. Further, hazels generally exist on the forest edge, suggesting a patchwork of forest across the island.

Lesser Celandine tubers

Seeds of White & Yellow Water Lily have been recorded at several Irish Mesolithic sites, sometimes in large quantities, highlighting the importance of water-saturated environments. While water-lilies naturally produce large numbers of seeds, their recovery from archaeological deposits in a charred state suggests human consumption. What’s really interesting about water lily seeds as a food source is that they have a super-intense processing need. It involves gathering the seed capsules, fermenting them in water, followed by cleaning of seed, dehusking, winnowing, parching, grinding, and then roasting. The process takes a minimum of two weeks, highlighting the extensive time involved in the processing of these plants. Alternatively, the seeds can be fried in fat to make a kind of popcorn.

“Popped” Water Lily seeds

Surprisingly, fishing structures and fish baskets provide some of the clearest evidence of human activity and indicate extensive woodland management. Four almost complete baskets were identified alongside some additional fragments that may have belonged to other baskets. The baskets were manufactured from alder, birch, and wood assignable to Rosaceae. The components of the baskets were narrow, only a few centimeters in circumference, and 1–2 years old when cut. Most importantly for this discussion, five Mesolithic fishing structures, predominantly made from hazel, were found 20 feet below mean sea level in the River Liffey, Dublin as part of archaeological investigations in advance of building works. The five structures consisted of wattle fencing, stake rows, and a basket trap, and provided a rare opportunity to examine in detail wooden structural material datable to the Mesolithic. 

Based on analysis of the age profiles of the wood remains from the River Liffey, the poles used ‘‘came from coppiced woodland’’. From the age profiles, it is surmised that the ‘‘hazel used in the construction of these traps was on a coppice rotation cycle of 8–9 years, with another possible cycle indicated at 5 years’’.

Climate Change

Now, I want to look at a bit of a bigger scope for a second, because Ireland’s ecological history speaks to how humans interact with landscapes. As the ice age waned, juniper took hold as the predominant tree of Ireland, only to be then replaced by birch. Hazel followed, and pine, elm, and oak became the dominant tree across the island by 7,000 BC.

Enter— humans. Humans arrive and restart the successional clock to bring back the species they want to eat. This would have created landscape mosaics, forming a variety of early-successional plant communities and ecotones, as evidenced by the charred remains from archeological sites. Such clearances would have functioned in several different ways, from opening up space for grazing animals, whether they were as livestock or animals brought in to eat the things they didn’t want to, like acorns, and for optimizing fruiting conditions for nuts or berries. 

So let’s fast forward a bit. Around 6,000 years ago, or 4,000 B.C., we have the first clear documentation of domesticated animals in Ireland; cow bones.⁴ However, oddly enough, there isn’t much evidence of this, suggesting that people may have actually experimented with animal agriculture and then rejected it. However, the island was just beginning to experience rapid climate change, which significantly reworked the landscape.

Recent work on dendrochronologically-dated bog oaks suggests that Ireland was affected by a series of climatically-driven hydrological changes between 4100 and 3200 BC: drier conditions started around 4100 BC, with wetter conditions evident from 3620 BC, lasting about 300 years. There’s also clear evidence of an extremely severe climatic downturn around 3190 BC, suggesting that the second half of the 4th millennium was a time of climate uncertainty.⁵

This climate change wasn’t just tied to Ireland, but had implicated in the transition to agriculture in all of north-west Europe and has become the focus of several recent investigations. The other major event associated with the onset of agriculture, traditionally placed at around 4000 BC, is the Elm Decline.⁶ This is characterized by a decline in the presence of Elm in many pollen diagrams across north-western Europe. In Ireland, the event is frequently accompanied by some of the first, indisputable evidence for agriculture, linking it to anthropogenic activities; more recently, other explanations have been proposed, like climate change or disease. Despite providing a range of over 1000 years from 4400 B.C. to 3100 B.C., most research accepts that the Elm Decline was a ‘catastrophic, uniform phased event’. Pollen work indicates a change in the use of landscapes came about in order to support the ‘new economy’.

While we have strong evidence for extensive forest clearance in some parts of Ireland, in other parts the situation is much less clear, with more ambiguous episodes of clearance or very low levels of activity. The diversity we see within the published pollen record suggests that the organization of the landscape varied regionally and temporally. The association between early agriculture and the Elm Decline seen in many pollen diagrams shows that this latter event was not synchronous across the entire island, starting earlier in the north compared with the west, but that there is a strong coincidence with early agriculture at many sites.

After this early boom, there are changes in the nature of settlement records. From around 3400 BC, we see a decrease in the frequency of cereal evidence and an increase in some wild resources such as fruits, but oddly not nuts, in the records, alongside evidence for re-afforestation in pollen diagrams over 500 years until 3,000 BC.⁷ This period seems to have been one of environmental, landscape, settlement and economic change.

A Flattening of History

After decades of debate, ancient DNA is now providing strong evidence that Ireland and Britain were at the western end of a long process of population movements involving the spread of farmers ultimately of Near Eastern ancestry. The arrival of farming coincided with new ways of living, including the introduction of pottery, grinding stones such as saddle querns, substantial rectangular houses and mortuary monuments for the dead. Ceramic vessels provided new ways of storing, processing, and presenting foods, while querns enabled new ways of processing foods. Their new houses provided new arenas for the storage, preparation, and consumption of foods, introducing new ways in which people came together to share a meal. 

A rotary quern.

It’s important to understand we are talking about multigenerational periods, tens of generations in some cases. These weren’t overnight changes. And further, when we’re talking about this period of 10,000 years or so, that over that period, while we were receding from the ice age, there were blips of quick heating and repeated cooling which likely played into these changes, and of course these changes impacted things like sea level rise. So when we talk about farming and staying in place, we are not talking about like, one generation decided to stop moving and that was that. These periods of change have been documented as being typically periods of intense strife, with people fighting over how they wanted to live, especially when farming took place in the places where the most fertile lands, which were also the most productive sites for foraging.⁸ 

These were not easy transitions, and some will argue that these weren’t necessarily progress to this day. That said, the first evidence of cereals in Ireland is dated around 3750 BC. Emmer wheat dominated, with barley also recorded. Plant remains continued to be recorded at later Neolithic sites, but cereals were often absent, suggesting a shift away from arable agriculture or perhaps a change in the processing of cereal foods or deposition of food remains that has left little trace in the archaeological record. This may have been a part of that long history globally of refusing to settle into agricultural societies, and this may have been a period where they returned to a hunter-gatherer format.

In areas where cereals were common, animal bone was most often found. In many cases, these remains were very small and were not identified further than indeterminate animal bone, particularly so in the case of burnt bone. Where identifiable, cattle and sheep/goat were dominant, closely followed by pig. ⁹ At sites where cereals were recorded, ceramic vessels were also often present, and at sites where cereals were absent, ceramics were often absent too. In recent years, residue analysis has been carried out on ceramic vessels from Neolithic sites in Ireland, providing clear evidence for predominantly dairy products and, less often, meats in vessels. This all reinforces that one was not done without the other— whether it was the ceramics, the cereals, or the livestock.

So why are we talking about this?

Ireland in particular is a useful example of people intensively managing a landscape in a variety of ways, while also dealing with massive climate change and adjusting their lifestyles accordingly.¹⁰ That’s not to say what they did was right, perfect, or what everyone agreed to, hence the ebbs of agriculturalism, and we’re painting in very broad strokes, but I think it also highlights places where selective breeding could be incredibly useful, as many of the species we highlighted haven’t been selectively bred.

The most commonly documented food source continued to be hazelnuts during this time, followed closely by cereals. That said, various apples, raspberries, flax, and even some occasional evidence of peas existed during this time. Flax was actually one of the earliest crops to be cultivated in Ireland. Selective crops for farming were mostly focused on cereals, and the most common crops that were imported were einkorn, emmer wheat, naked & hulled barley, flax, peas, lentils, chickpeas, and even bitter vetch, all of which slowly crossed Europe and making it to Ireland almost 3,000 years after reaching Greece.

Ireland also inherited some other trappings of agriculture as they began to use these crops, including using long-lived plots and not changing their growing location for long periods—meaning plots of land would be used for a decade or more at a time.¹¹ The consequences of farming are well known as it led to various forms of land clearance which, over millennia, changed the Irish landscape. ¹² Obviously, production in farming is influenced by several factors including changes in farming practices, developments in cultivation methods — that is both in terms of technology and cropping systems, export of produce, and the size of the population living off the land. What’s really important in this conversation about Ireland in particular is the the natural tendency of soils in a humid environment to become acidic and nutrient-depleted over time, much like we see in the tropics. 

These farmers saw this happening and decided there were a few methods to help return nutrients to the soil and neutralize the pH. The first had to do with using livestock. It was the introduction of cattle and perhaps to a lesser extent sheep that were to have more immediate and significant consequences.¹³ Now, if one examines Ireland’s distinctive ecological background there is one very significant reason why the introduction of cattle to Ireland was so important. Aside from the fact that several large mammal species were, and are, absent from Ireland, the crucial fact is that most of the large mammals present in mid-Holocene times in adjacent parts of Europe were not present in Ireland.¹⁴ 

Aurochs, elk, roe deer, and even red deer were absent.  So now these new animals create a completely new dynamic to the landscape. They grazed the forests and the grasslands of the island heavily. And while they can return nutrients to the soil, manures can only return part of the nutrients removed in grazing and cropping and hence a search for ‘new’ materials, many of them geological, was, and continues to be, an unending task. Marls and calcareous clays at shallow depths were early targets for experimentation. Coastal areas were, and still are, prolific sources of ‘sea manures’, including sand, shell, coral and seaweed. Paring and burning the organic surface of soils was a ‘stop-gap’ measure to release calcium, magnesium and potassium, but the element in greatest demand, both by crops and animals, was often phosphorus. The ancient practice of burning animal bones in midsummer and scattering the embers and ashes on crops indicates the need, long-recognized by farmers, to augment soil phosphorus. 

The problem is that animals eat up the phosphorus and the mineral is largely trapped in their bones. The phosphorus content on the soil is at a fixed amount, and if a certain percentage is trapped in living bones, like on loan, and we know how long it takes for those minerals to return to the soil, then there’s a flow problem, right?

The manure from the sheds of cattle and other livestock was piled in a dunghill in the farmyard. In autumn, the manure was brought out to the fields in a cart. Despite the recycling of waste products to the soil, nutrients continued to be lost under the humid Irish climate even though nitrogen fixation, through the agency of clover and other leguminous plants, helped maintain adequate nitrogen levels in the soils.

Not only did farmers try to use animal waste to keep the soils healthy, but they also recognized the benefits of burning surface vegetation, specifically when things like heath took over, which offered little nutritional benefit for livestock or people. Additionally, these indigenous people used shells to try to neutralize the soils, in a similar way that we use lime today. It was documented that they’d fill boats with shells and bring them back into the mainlands, and not only this, but they only used shells that had been underwater, which would have a higher sodium content, suggesting they understood the need for livestock to have access to salt as well. Not only did they use shells from the ocean, but they also incorporated marl, a lime-rich mud-turned rock that exists under peat bogs as a soil amendment

Seaweed has also played an important role in maintaining soil fertility and creating soils in Ireland particularly in coastal areas. Seaweeds grow profusely on, and are invariably anchored to, rocky substrates on most of Ireland’s extensive coastline. Grazing of seaweeds, especially by sheep, is well known for some Scottish islands,and there are even early medieval references to it being eaten by cattle in Ireland. Despite the harvesting and collecting hazards and its heavy weight when wet, seaweed has a long history of use in many coastal regions of Europe. There is some evidence that in prehistoric times it was used as a fertiliser but it is mainly from medieval and later times that there is considerable evidence.

All of this points to the fact that land management, or rather, balancing ecosystems with humans doesn’t necessarily mean that we are in some yoga-hippie “one with nature” thing where we simply exist, walking around and making a couple small changes here and there and in return we have insane abundance. It’s not that simple, and with climate change we have a bigger responsibility to keep systems going. What we see in Ireland is important in understanding what our future looks like. People are going to try different methods to deal with climate change— some will want to go back to how things were, whether that means pre-fossil fuel here, or hunter-gatherer, or maybe even try to keep chugging along, all while other folks will try to find a way to mix our past and our present to create the most amount of variety possibly to weather any storm.

It’s also worth noting that during these abrupt changes, there was a significant population dropoff, and the technology applied in managing landscapes also seemed to have dropped off as well. The current leading argument on the subject is that the low populations couldn’t maintain the complex technologies. However, what came out of it is kind of interesting. Because they quote-unquote ‘slid back’ to older technologies while having ancestral knowledge of newer technologies, they were able to improve on those older technologies from there experiences with the newer technologies, something I think that could be important in our future.

That said, I should point out that this is significantly up for debate. Like I said, we’re talking in broad strokes here, literally a thousand years. So not only does correlation not equate to causation, but we are discussing incidents as though they happened cohesively and fluidly when we would be talking about multiple generations. Yet, this is all helpful as we start to think about what a post-collapse, climate-change reframed ecology looks like. We can’t go back, and we can’t stay as things are. But, we can take the things we’ve learned and apply them to some more traditional practices.

Lastly, this piece was researched a few years back originally, and my notes weren’t as thorough, but all of the sources for the content highlighted here *should* be listed below. I attempted to match them the best I could.

If you’ve enjoyed this piece, which is equal to a 15-page chapter, of (so far) a 1035-page book with 690 sources, you can support our work in a number of ways. The first is by sharing this article with folks you think would find it interesting. Second, you can listen to the audio version of this article in episodes #78, of the Poor Proles Almanac wherever you get your podcasts. If you’d like to financially support the project, and get exclusive access to our limited paywalled content, you can become a paid subscriber on Substack or Patreon, which will both give you access to the paywalled content and in the case of Patreon, early access to the audio episodes as well.

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2. https://www.irishexaminer.com/property/homeandgardens/arid-30960075.html

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8. Snoeck, C., Jones, C., Pouncett, J., Goderis, S., Claeys, P., Mattielli, N., Zazzo, A., Reimer, P. J., Lee-Thorp, J. A., & Schulting, R. J. (2020). Isotopic evidence for changing mobility and landscape use patterns between the Neolithic and early bronze age in Western Ireland. Journal of Archaeological Science: Reports, 30, 102214. https://doi.org/10.1016/j.jasrep.2020.102214

9. McClatchie, Meriel, Schulting, R., McLaughlin, R., Colledge, S., Bogaard, A., Barratt, P., & Whitehouse, N. (2019). Food production, processing and foodways in Neolithic Ireland. Environmental Archaeology, 27(1), 80–92. https://doi.org/10.1080/14614103.2019.1615215

10. Whitehouse, N. J., Schulting, R. J., McClatchie, M., Barratt, P., McLaughlin, T. R., Bogaard, A., Colledge, S., Marchant, R., Gaffrey, J., & Bunting, M. J. (2014). Neolithic agriculture on the European Western Frontier: The Boom and bust of early farming in Ireland. Journal of Archaeological Science, 51, 181–205. https://doi.org/10.1016/j.jas.2013.08.009

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