by Michelle Farrell (@DrM_Farrell)
As I
mentioned in my first GEES-ology
blog post,
palynology can be applied, along with a whole host of other scientific
techniques, to help answer archaeological questions. One of my main research
interests lies in understanding how people interacted with their
environments during prehistoric times – not just the ways in which human
activities may have impacted upon the environment, but also the effects that environmental conditions may have had on the development of human culture and
society. I am particularly interested in how these human-environment
relationships may have differed in areas that are currently perceived to be
marginal for human settlement, and especially in island environments where
finite natural resources would have been available.
To date, my
research in this field has focused on the islands of Orkney, situated about 10
km off the northern coast of
Scotland.
This apparently open, hyper-oceanic environment would presumably have provided
quite marginal conditions for human settlement, yet Neolithic communities
flourished and the islands contain some of the most spectacular remains of this
period in north-west
Europe. The importance of
these monuments is reflected by the designation of the
Heart of Neolithic Orkney World Heritage Site, which includes
the settlement of
Skara Brae, the chambered tomb of
Maeshowe, and the ceremonial sites of the
Stones of Stenness
and the
Ring of Brodgar.
 |
One of the houses at the Neolithic village of Skara Brae,
occupied between about 3200 and 2500 BC |
 |
| The Stones of Stenness in west Mainland |
 |
Berriedale Wood in northern Hoy: Britain's most northerly natural woodland,
and the only patch of native woodland surviving in Orkney today |
It has
generally been argued that the Neolithic structures of Orkney have survived so
well because they were built in stone - the use of stone for construction seems
to have been rare elsewhere in
Britain
at this time. Orkney today is largely treeless – in fact the only natural
woodland to be found on the islands is that at
Berriedale
in northern Hoy, which actually represents the most northerly natural woodland
in the British Isles. There is a long-held assumption that Orkney has been
devoid of substantial woodland throughout much of the Holocene (the period of
time since the end of the last ice age, approximately 11,500 years ago, to the
present day). Was the use of stone for construction in Neolithic Orkney
therefore an environmental necessity?
 |
Yesnaby in west Mainland serves to demonstrate why the islanders
might have preferred to use flagstone for construction even if plenty of
timber was available! The flagstone easily breaks off along the
bedding planes in perfect, evenly sized slabs ready for building. |
Palynological
investigations carried out in the 1960s and 70s suggest that Orkney did once
have quite extensive tree cover, although high percentages of birch and hazel
pollen have led this to be dismissed as ‘scrub’ or ‘shrubland’ rather than true
woodland. These studies have often been used to provide context for the
Orcadian archaeological record, the story being that the islands were covered
with birch-hazel ‘scrub’ during the earlier part of the Holocene, which was
then almost entirely cleared for agriculture around 5500 years ago. This
apparently forced the islanders to the readily available Orcadian flagstone for
their construction materials.
Many of
these early palaeoecological studies were hampered by poor dating of the
sequences investigated, and when I plotted the dates of woodland decline from
previous reliably dated studies, along with dates from new cores that I worked
on for my PhD research, it became clear that the timing of woodland decline in
Orkney differed between locations. At several sites woodland loss occurred in
multiple stages, with fragments of woodland persisting into the Bronze Age in
places. So it seems that woodland was present in parts of Orkney throughout the
whole of the Neolithic period – but how valuable a resource would it have been
to the islanders?
The
tendency to dismiss prehistoric Orcadian woodland as ‘scrub’ has led to the
assumption that it would not have been particularly valued as a resource by the
inhabitants of the islands. Whilst it is true that the woodland was probably
largely made up of species such as birch and hazel, even birch-hazel canopied
woodland can be a useful and rich resource. In the North Atlantic region,
environmental archaeologists have identified the management of birch woodland
as one of the most pressing issues in the Norse and medieval periods. The uses
of birch wood range from domestic fuel to the production of charcoal for iron
smelting, and there is palynological evidence from Greenland
that birch woodland was being sustainably managed, indicating the importance of
the resource to the human population. In Iceland, woodland was managed by
coppicing and access to woodland was controlled by the more powerful members of
society. Coppice management of woodland has been practised in Europe since the
Mesolithic period (c. 9000-4000 BC),
with evidence provided by artefacts such as fish traps found in Ireland and Denmark. There seems to be no
reason why the birch-hazel woodland of Orkney should not have been similarly
valued for the range of resources that it would have provided. In fact, there
may have been greater diversity in some areas, with the possibility that
species such as oak and pine also grew on Orkney, and this would only have
increased the range of possible uses and value of the resource. More on this in
a future blog post!
 |
Remains of one of the wooden structures at Braes of Ha'Breck: the large
post holes which would have held the timber uprights are clearly visible |
The final
question to be answered is whether the woodland of prehistoric Orkney would
have been capable of providing timbers that were substantial enough for
construction. Until recently, the only early Neolithic settlement known in
Orkney was that at
Knap of Howar on Papa Westray,
which was built in stone at a time when early Neolithic houses elsewhere in
Scotland were constructed from timber, thereby apparently supporting the
suggestion that the predominance of stone architecture in Neolithic Orkney was
a consequence of a lack of timber resources. In recent years early Neolithic
buildings have been discovered at several other locations in the islands, with
a wide range of architectural styles now recognised from this period. The remains
of wooden structures at Wideford in west Mainland and the
Braes of Ha’Breck
on the island of Wyre clearly demonstrate that timber resources were exploited
during the earlier part of the Orcadian Neolithic. Whilst it is probable that
at least some of this timber was derived from driftwood, recent palynological
evidence has shown that local woodland could have provided a more reliable
resource. The archaeological evidence from Braes of Ha’Breck suggests that
whilst in some cases timber buildings were directly replaced with stone
structures, others may have been contemporary with them. Although stone
buildings appear to have been predominant in the later phases of occupation at
this site, large structural timbers continued to be used within them. A small domestic
quarry on the site appears to have been exploited for its stone during the
early Neolithic, when buildings were being constructed from wood, and was apparently
filled in and no longer used during the later Neolithic, at a time when it has
been suggested that people were turning to flagstone as a substitute for
timber. This was also a period of rapid social change, and the combination of
palynological and archaeological evidence suggests that the shift from timber to
stone construction in the mid 4
th millennium BC in Orkney can no
longer be explained simply as a consequence of a lack of timber resources.
Rather than being an environmental necessity, it more likely reflects
underlying social and cultural changes.
This blog post
is based on the following article, which can be accessed
here:
Farrell,
M., Bunting, M.J., Thomas, A. and Lee, D. (in press) Neolithic settlement at
the woodland’s edge: palynological data and timber architecture in Orkney,
Scotland. Journal of Archaeological Science (2012),
doi:10.1016/j.jas.2012.05.042.
