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
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
“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”
of the Lords of Council in Civic Causes II’ (1496 - 1501) p. 350 - NMS.
& 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
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
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.
a Major 20th Century use for Seaweed
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
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.
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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