A clearance cairn is an irregular and unstructured collection of fieldstones which have been removed from arable land or pasture to allow for more effective agriculture and collected into a usually low mound or cairn. Commonly of Bronze Age origins, these cairns may be part of a cairnfield (a collection of closely spaced cairns) where some cairns might be funerary. [1] Clearance cairns are a worldwide phenomenon wherever organised agriculture has been practised. [2] [ page needed ]
By removing large and moderate size stones from the surface and sub-surface, ploughing can take place with much less potential damage taking place to the plough blade. Stones also prevent the growth of plants where they physically block access to the soil and their removal allows for a greater surface area for crops to grow and to allow for plants to grow to their full potential; Stones also increase drainage and may therefore deprive plants of moisture. Stones were removed from fields to allow for the efficient use of hand tools, animal powered machines on such fields in the past and for tractors, etc. in more recent times. Some prehistoric clearance cairns may also contain burials. [3] A few clearance cairns may have been additionally created as boundary markers. [4] As ploughing developed and specialised the greater depth tilled and the increased power of mechanised ploughing resulted in more and larger stones being brought to the surface and these too had to be removed.
Field clearance cairns sometimes survive long after cleared fields have fallen out of use and are often the only surviving evidence of past agricultural activity in areas of woodland, upland areas, etc. The existence of these cairns was once regarded as suggesting pastoral farming. Many now consider them the result of arable or mixed agricultural exploitation enabling ploughing or hand tillage to work more efficiently.
Cairns built in the middle of enclosures can maximize the effect of daytime radiance, since reradiating absorbed sunlight from the stones raises nighttime field temperatures (very slightly) as in walled gardens. Since this effect would encourage crop growth (and potentially reduce the risk of frost) it may have been deliberately intended, though there is no direct evidence that cairns were built for this purpose. [5]
Many clearance stones were used in the construction of defensive structures, houses, farm buildings, walls, drainage ditches, road metalling, etc. Where permanent clearance cairns were formed it was predominately on waste land, such as steep slopes, edges of woodland, field corners, and around earth-fast boulders[ definition needed ].
The amount of stone which needed to be cleared from a field depended upon geology, glacial deposits, glacial erratics, etc. Many cairns are mainly composed of stones which could have been carried by a single person who would have followed the plough as it turned up small boulders, etc. Most surviving cairns are from the Bronze Age but some are considerably older, because field clearance has been practised since the beginnings of agriculture in the Stone Age (such as at the Gardberg site in Vestre Slidre, Oppland, Norway). [5]
Cairns may be discrete, in large groups (cairnfields) or as linear formations—linear cairns. Many stones in clearance cairns show plough-marks or ard-marks at various angles to each other, typical of the Bronze Age ploughing methods. [6] These ard-marks indicate that the boulders were obstructing the ploughing process and were in situ for some time before removal.
Other items such as bog-wood and grubbed out tree stumps were sometimes added to the cairns as a result of tree felling and the process of creation of pasture from woodland. Bog-wood stumps and trunks can be thousands of years old, are darker in colour due to the tannins from the peat and do not show typical wood decomposition characteristics due to their preservation within peat bogs. The absence of saw marks indicates felling using axes, providing further information about the age of the wood involved.
Some clearance cairns are linear in form. Many of the smaller cairns were probably created by family groups, whilst larger ones would have required organised labour. [2]
Cairnfields have on occasions been confused with various other classes of monuments, such as round barrow cemeteries and groups of round barrows, stone hut circles, ring cairns, or burnt mounds. In general round barrows are larger, more regular, and may contain visible traces of a cist or kerb; stone hut circles have distinct entrances; ring cairns have a hollow centre; and burnt mounds contain a high proportion of fire-crazed stones of rather smaller size than appear in the average clearance cairns within cairnfields.
Natural deposits such as so called 'clitter agglomerates', moraines can also on occasion look rather similar to groups of clearance cairns, but their context, position and regular form usually betrays their true origins. [7]
Clearance cairn material is often heterogeneous, typically consisting of both edged and rounded small stones, sometimes mixed with sand, clay or silt, lifted from the field nearby. Agricultural and clearance cairns are sometimes located on slopes, whilst burial cairns rarely are. [8]
Clearance cairns constructed using mechanised methods with horse or motor powered assistance may appear superficially similar, however the stones are generally much larger and they are more randomly tipped rather than hand placed.
Due to the age and 'abandoned' state of many clearance cairns, they are often good sites for the growth and survival of lichens, mosses, ferns and other plants; the actual species being dependent on the rock type. Cairns are relatively undisturbed and emulate old walls for the micro-habitats they produce. [9]
In some areas which are now unproductive moorland, aerial photographs show the presence of numerous prehistoric clearance cairns and associated dwellings such as hut-circles. This clear evidence of previous ancient habitation and cultivation shows that the climate worsened until the farmers were forced to move to lower ground. [10]
Stone carry or the stone walk is a traditional Scottish athletic event involving the carrying of large stones down the field of competition; the competitors pick up two heavy stones with iron handles, and carry the pair as far as they can. The sport may have grown out of the act of clearing stones from fields to create pastures and arable land.[ citation needed ]
A cairn is a human-made pile of stones raised for a purpose, usually as a marker or as a burial mound. The word cairn comes from the Scottish Gaelic: càrn.
The Carneddau are a group of mountains in Snowdonia, Wales. They include the largest contiguous areas of high ground in Wales and England, as well as six or seven of the highest peaks in the country—the Fifteen Peaks. The range also encloses a number of lakes such as Llyn Cowlyd and Llyn Eigiau, and the Aber Falls waterfall. It is delimited by the Irish Sea to the north, the Conwy valley to the east, and by the A5 road from Betws-y-Coed to Bethesda to the south and west. The area covers nearly 200 square kilometres (80 sq mi), about 10% of the area of Snowdonia. The area is bordered by three main roads—the A55, the A5 to the south and the A470 to the east.
The ard, ard plough, or scratch plough is a simple light plough without a mouldboard. It is symmetrical on either side of its line of draft and is fitted with a symmetrical share that traces a shallow furrow but does not invert the soil. It began to be replaced in China by the heavy carruca turnplough in the 1st century, and in most of Europe from the 7th century.
The study of field systems in landscape history is concerned with the size, shape and orientation of a number of fields. These are often adjacent, but may be separated by a later feature.
Parc Cwm long cairn, also known as Parc le Breos burial chamber, is a partly restored Neolithic chambered tomb, identified in 1937 as a Severn-Cotswold type of chambered long barrow. The cromlech, a megalithic burial chamber, was built around 5,850 years before present (BP), during the early Neolithic. It is about seven 1⁄2 miles (12 km) west south–west of Swansea, Wales, in what is now known as Coed y Parc Cwm at Parc le Breos, on the Gower Peninsula.
Boat How or Eskdale Moor is a hill in the English Lake District, near Boot, in the Borough of Copeland, Cumbria. It lies south of Burnmoor Tarn, between the River Mite to the west and the Whillan Beck tributary of Eskdale to the east.
Shap Avenue is the name given to a, now mostly destroyed, megalithic complex near the village of Shap in Cumbria, England, comprising at least two stone circles, a two-mile avenue of megalithic standing stones, and several adjacent burial mounds. Before its destruction, it was one of the largest megalithic monuments in Europe. As it survives today, the site comprises a rough and highly damaged avenue of stones arranged over a mile, aligned northwest. At its southern end is the avenue's terminal, a stone circle named 'Kemp Howe', which has been mostly buried by a rail embankment.
A ring cairn is a circular or slightly oval, ring-shaped, low embankment, several metres wide and from 8 to 20 metres in diameter. It is made of stone and earth and was originally empty in the centre. In several cases the middle of the ring was later used. The low profile of these cairns is not always possible to make out without conducting excavations.
Foel Chwern is a Round cairn on the edge of the high plateau east of the Neath valley, and near the summit of Craig y Llyn. The headwaters of the River Rhondda are to the south-west. It is a burial monument dating to the Bronze Age, and is sited on the edge of a steep scarp slope, with a wide field of view to the north. The long distance footpath Coed Morgannwg Way runs close by the cairn. Conifer plantations of the Rheola Forest surround the site.
The Crawley Edge Cairns are a series of forty-two Bronze Age round barrows, cairns and clearance cairns located in a field in Crawleyside, near Stanhope, County Durham, England.
Agriculture in prehistoric Scotland includes all forms of farm production in the modern boundaries of Scotland before the beginning of the early historic era. Scotland has between a fifth and a sixth of the arable or good pastoral land of England and Wales, mostly in the south and east. Heavy rainfall encouraged the spread of acidic blanket peat bog, which with wind and salt spray, made most of the western islands treeless. Hills, mountains, quicksands and marshes made internal communication and agriculture difficult.
Alteen is a townland in the civil parish of Kinawley, barony of Tullyhaw, County Cavan, Ireland. The local pronunciation is IL-Keen. A sub-division is called Tullynahunshin.
Gibbet Moor is a small gritstone upland area in the Derbyshire Peak District of central and northern England, near the village of Baslow. Its highest point is 295 metres (968 ft) above sea level. The Chatsworth Estate lies to the west and Umberley Brook runs along its east edge. East Moor is the broader moorland area covering Gibbet Moor, Brampton East Moor and Beeley Moor. Gibbet Moor is a prehistoric landscape with several protected scheduled monuments.
This is a list of scheduled monuments in the district of Derbyshire Dales in the English county of Derbyshire.
This is a list of scheduled monuments in the district of High Peak in the English county of Derbyshire.
This is a list of scheduled monuments in the district of North East Derbyshire in the English county of Derbyshire.
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