The Earliest Uses

As the glaciers receded after the Ice ages, the land we now know as Scotland was freed for human habitation. It is known that small groups of hunter-gatherers were establishing themselves and settling (on the island of Rum, for example), certainly by 4000 BC. The bounty of the sea would have been essential to the success of these people, and seaweed would have been an easily gathered, abundant foodsource.

It is not until the 600s AD, however, that we have a categorical, written record of seaweed use - in a poem (questionably) attributed to St. Columba, himself.  In this there is a reference to the monks of Iona collecting dulse (Palmaria palmata) from the rocks.

Dulse has provided a staple part of the diet of crofters throughout the North West coast, often eaten with oatmeal in a thick broth, or simply boiled and served with butter as a separate dish.  The Reverend Landsborough (1849) stated that it "is a favourite ingredient in ragouts, to which it imparts a red colour, besides rendering them of a thicker and richer consistence." This species was also in use in various folk remedies, such as ‘sticking plaster’ or poultice substitutes and vermifuges (against intestinal parasites).

Dulse was also sold on the East coast, in Angus, Fife and Lothian even up to post-Victorian times. It was eaten after cooking it in the embers of a fire for a short time and smothering it in vinegar. Other species, such as Alaria esculenta and Laminaria saccharina (the ‘sugar wrack’) were also available from street vendors in Edinburgh.

Another species, carrageen (Chondrus crispus) was also commonly used in the Hebrides, primarily to make a jelly-like pudding. Some people still use these species in the traditional manner, although seaweeds can now be obtained in health food shops as well as on the shore.  A number of other species have also found their way into the diet of the people of the Highlands and Islands, including Himanthalia elongata. The button-like bases of the leaf-blade of this plant were used as an ingredient in a sauce served with poultry.

As well as food for humans, some species have been used extensively as animal fodder, the early farmers probably having noted the willingness of deer and cattle to graze from the foreshore. Sea ware used to be collected as fodder for cows in the Hebrides throughout the winter months, freeing up stored crops for humans and young livestock. A portion of the porch in the 'black houses' of the crofters was often devoted to storing the seaweeds.

The fuci of brown seaweeds were sometimes boiled with oatmeal, hay, chaff or oat husks, as a winter fodder.  The main species used were Pelvetia canaliculata and Ascophyllum nodosum. In the area around Loch Feochan, the former used to be fed to pigs, particularly when they were being fattened for market, as it has a high fat content. It was given raw, or else boiled with oatmeal if it was to be given to calves also.

As seaweeds are abundant, nutrient-rich and alkaline, they are particularly suited for use as a fertiliser on Scotland’s generally acidic soils. It is mainly the large, brown species which are used. In the past the plants were taken from winter storm-cast and dug directly into the soil after a short period of composting. The linear ‘lazy beds’ used by the crofters can still be seen in use today. It was said that a crofter with an adequate supply of seaweed would be able to grow two crops of oats in successive years in the same plot, without the need for rotation. If estates only had a small frontage on the sea the seaweed was generally shared amongst the inland crofters as well.

In the areas around Ayr and North Berwick the abundance of seaweed was a great boon to the farmers.  Even as recently as the 1960s, a proposed seaweed processing plant in East Lothian had to be shelved as it would have used up all the seaweed the farmers needed.  Thus, on both the crofts of the Highlands and on the lowland farms, seaweed was considered a valuable resource for any farmer. There is a record of a civil court case in 1499/1500 which illustrates this importance - an action brought against one Thomas Maule by two complainants for (amongst other things):

“Stoopping of Thame fra taking of wair of the sey to lay apone the sadis landis for the gudeing thairof as was usit and wont in tymes bigane”

“Stopping [the complainants]  from taking seaweed from the sea, preventing [the complainants] using it as a fertiliser as has been the past custom”

Soda Potash & Iodine - 17th - 20th Centuries

In the late 1600s, a new use for seaweed was discovered which was to provide a major industry for the Western Isles and Orkney archipelago. Extraction of soda and potash  from Fucus spp., Ascophyllum spp. and Laminaria spp. provided a ready supply of these chemicals for the British isles. This allowed independence from the other main centre of production in Spain, where the chemicals (called barilla by the Spanish) were extracted from another coastal plant, the glasswort (Salicornia spp). This was to be of particular significance during the Napoleonic and later wars, when Britain was isolated from mainland Europe.

The practice had been introduced to Scotland in the late seventeenth Century. There are records of its first appearance in Anstruther (Fife) in 1694, and Martin Martin (1695) mentions the potential for the industry in the Hebrides.  By 1722 the practice had spread to the Orkneys, brought by an Orcadian entrepreneur named James Fea.  Fea brought a man named Meldrum (who was well versed in the practices of the industry) over to the islands from Fraserburgh.  Meldrum appears to have been a bit of a confidence trickster, and attempted to convince the islanders that he should have a monopoly on the kelp industry, as he was the only person to know the 'magic words' and possess the 'magic powder' that made the plants burn thoroughly.  The islanders quickly saw through this, though, and a thriving kelp industry was soon established. There was nevertheless some local objection to the practice, culminating in the 'Kelp Riot' of 1762. The instigators claimed in court that  cattle were taking ill and that a number had died from inhaling the smoke of the kelp fires. The 'lampods' (limpets) growing on the rocks were reportedly dying as well, thus depriving locals of two significant portions of their diet.

By the 1740s, the Hebrides had also adopted the practice and the industry became a very significant source of income for the peripheral regions of Scotland.  The Western Isles and Orkney archipelago were the main centres of kelp ash production. In these areas, even unpopulated offshore islands were exploited and collectors would stay in makeshift huts, the remains of which can still be seen today.

There was relatively little kelp burning on Skye (where the first appearance of the industry was as late as 1758) and the more southerly islands, and there was almost no kelp ash industry to speak of in Shetland and the southern Ebudes.  Mull did have a modest industry at one time, centred around Loch na Keal, which brought in around £12,000 - £15,000 a year (over three quarters of a million pounds in today's terms).

Soda and potash were important chemicals in the soap and glass industry and were widely used for linen bleaching. The extraction process involved burning the kelp in large, often stone-lined trenches (or circular pits in Orkney). In the Hebrides the floor of the kiln was left with a constant basal layer of kelp called the 'unlar'. Here, it was burned for some four to eight hours, the fire kept going with the help of heather and hay. The womenfolk would often watch the fire and make the adjustments needed to keep it going steadily: a job requiring considerable skill.  When the fire was going well, men with long-handled iron mallets or hooks ('kelp irons') would pound the weed into a mass. It would then be covered with stones and turf to protect it against moisture, and left overnight.  The following morning the chunks of kelp ash would be cool enough to be broken up into lumps for transportation by boat to Leith, Dumbarton, Glasgow, Newcastle, Liverpool and Bristol.

The crofters would work from early June to the end of August at kelp burning, to subsidise (and later almost replace) their agriculture and animal husbandry.  There is no doubt that the work was back-breaking and a rise in the cases of arthritis during the heyday of the industry has been attributed to carrying huge loads of seaweed. In addition to the physical hardship of the job, the practise became such a get-rich quick scheme for unscrupulous landlords that all the people of an estate would be set to work on the seaweed. This resulted in neglect of the land, and Stronsay, one of the major centres of production, must have appeared a truly hellish place, with the return of the land to fallow wilderness and the perpetual smoke and fire of the burning trenches surrounding the island.

Although landlords could make a lot of money (at one time the industry was worth the equivalent of seven and a half million pounds a year to the Hebrides alone) very little of this ever found its way to the workers.  In the early 1800s, however, the discovery of mineral deposits of potash in Stassfurt, Germany, crippled the industry and it went into a speedy decline. There was a short period of respite when a process for extracting iodine from the kelp ash was discovered, but this was short lived as mineral deposits of iodine were discovered in Chile.  The economy of these ‘peripheral’ communities was hit hard by the loss of the industry, and a considerable depression ensued. Although attempts were made to revive the industry during World War I the practice is now all but forgotten.
 

Alginates, a Major 20th Century use for Seaweed

Just prior to the Second World War, a new group of seaweed-derived chemicals were investigated, the alginates. These had been discovered in 1881 by E.C. Stanford, a scientist working on Laminaria spp. in Scotland. Alginates are jelly-like carbohydrates and are used for their water holding, gelling, emulsifying and stabilising properties. These properties are desirable in a wide range of applications. In the food industry they serve to stabilise meringues and ice cream, to improve the head on beer, allow fast-setting in puddings, emulsify oils and so on (as E-numbers 400 to 405). They also perform similar roles in the cosmetic, medical, paint and other industries and can be used to produce alkali-soluble fibres.

The Cefoil company, based in Campbeltown, was started in 1934 to produce sodium alginate fibre. With the onset of the war, the company came under the wing of the Ministry of Supply and three new plants were established, in Girvan, Oban and Barcaldine. Some investigation into the use of sodium alginate fibre as a component for aeroplanes was made and a single ‘seaweed’ De Havilland Mosquito was flown. Unfortunately, the material proved unsuitable and the company turned its hand to more conventional uses. After the war, Cefoil became Alginate Industries Ltd. and their main products became those in use today. Between Alginate Industries and the Scottish Seaweed Research Association (a research organisation based in Musselburgh) there was a flourishing of study into the whole process of obtaining and utilising seaweed products. The SSRA wound down over the 1960s, however and one of the factories (Oban) was shut in the 1970s.

In the past three decades, the industry has declined further. The alginates industry has been ‘adopted’ and passed around within a number of large international firms, which have allowed development and some slight expansion of the industry. Overall, however, the trend in Scotland has been one of decline, perhaps in imitation of the potash and iodine industries beforehand. This has been attributed to the ready availability of raw materials elsewhere (Chile and Tasmania), where the seaweed is generally dried and milled before shipping. Thus, supplies from far afield are often more economical than those from Scotland, as transport costs for the bulky, often undried, seaweed from the Hebrides to Ayrshire are prohibitively expensive. There have been several proposals for a drying and milling plant in the Hebrides but progress appears slow.

At present, little Scottish seaweed is being taken by the sole remaining alginate factory, at Girvan  and  the future for this industry in Scotland appears quite bleak.
 

The Current State of the Industry

There are a wide variety of small, dynamic businesses currently making use of seaweed in Scotland - mainly producing foodstuffs (especially for the health food market) and cosmetics.  One jewellery company produces a range of seaweed inspired pendants. The largest sector outside the alginates industry, however, is still fertiliser use. Many smallholders and gardeners collect a yearly load of seaweed for use in the traditional way, but there are also a number of companies which artificially compost Ascophyllum nodosum, using heat and pressure treatments to accelerate the natural process. These preparations are commercially available, although typically for the sports turf and agricultural markets. An expansion into smaller-scale production for home and garden use is likely - if marketing and packaging companies can be found.

So, all in all, seaweed use in Scotland can be seen to have a rich history, unfortunately underpinned by a boom and bust pattern. The industry has never stood still and has always had to reinvent itself to maintain even a modest success. Things may be changing now, as those working with seaweed are becoming more wary. With the increase in diversity of businesses and the recently heightened profile of seaweed amongst the general public there may be a more stable future for the industry.

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