Landscape archaeology and the ghosts of our worldwide arboreal heritage

Today, I received through the post the gloriously-titled booked ‘Working and Walking in the Footsteps of Ghosts – Volume 1: The Wooded Landscape‘. How evocative can a book title actually be? Surely not more so than this! And so I delved in to the contents page, to find an interesting chapter by Oliver Rackham, entitled ‘The Ghosts at the Ends of the Earth: Tree-Land in Four Hemispheres’. Below, I explore the chapter and convey its message to those who are reading this post.

When one is asked of the natural home of trees, the response may very likely be either woodlands or forests. Whilst these words do accurately describe the home of trees, they do not tell the full story. Wood pastures, or even landscapes void of any woodland characteristics, are also the natural homes of trees. Rackham describes five tree-land covers, and these are: (1) forest – trees grow characteristically close to one-another, and the ground flora is either non-existent or comprised of highly shade tolerant species; (2) savanna – grasslands and heathlands complete with trees, with ground flora being not of shade tolerant species; (3) coppice – sites are cut at intervals frequently enough to allow for light-demanding herbaceous species to flower; (4) farmland trees – those within hedgerow, or standing in isolation or in small groups within a worked field, and; (5) maquis – trees are reduced, as a result of browsing and burning, to the height of shrubs.

In  defining these five distinct trees-lands, Rackham then proceeds to explore such landscapes across the world, and delves into the historical attributes of current landscapes, in addition to other forms of historical evidence, that indicate the tree-lands of the past.

Coppice history

Rather profoundly, Rackham begins by making the assertion that woodland history resides not only within historical accounts, but also in the woodland features we can see today – such as giant coppice stools. Stools that support multiple stems of previously-coppiced broadleaved trees and exceed 2m in diameter act as living proof of centuries of coppice. Such stools are not limited to the UK either – France, Greece, Hungary, Italy, Norway, and many other European countries (and beyond – Japan also has a rich coppice history, as its native tree genera are similar to that of Europe) sport such massive stools. Curiously, for coppice to exist in two such areas of the globe, centuries before commercial travel and worldwide communication, means that human civilisation must have evolved along similar lines in both regions.

Turning attention towards Australia, Rackham notes that it is an entirely different ‘planet’ – mainly because species of Eucalyptus grace the landscape. Additionally, for what fungi do in Europe in terms of degrading coarse woody debris, fire does in Australia (though termites also play a role, albeit a smaller one). Eventually, fire was harnesses by man to artificially alter fire frequency in order to manage the landscape. Interestingly, this different means of recycling of the tree-lands complements Eucalypts, as they possess a permanent woody lignotuber that can sprout if the tree is killed by fire. Over the course of many fire events, such continues resprouting may in fact have a similar visual impact as coppicing does – a stool forms. Again, an archaeological indicator of past land-use by man, perhaps.

lignot
These eucalyptus are re-sprouting following a forest fire event. Eventually, Rackham suggests, these fire events may create multi-stemmed specimens akin to large coppice stools made by man. Source: Schoensleben.

Across the Pacific in North America, coppicing is also evident. Whilst the tree species are different to those within Europe, they could still be used by man as a perpetual (in theory) wood source. However, coppicing in North America takes on three different forms because active management of tree-lands has only been going on for 150-200 years. These forms are: (1) modest-sized coppice stools of the archetypal European coppice; (2) big stools where trees have resprouted from their lignotuber (common in Texas, where Native Americans worked the lands with fire for many centuries), and; (3) self-coppice stools, created by species such as Tilia americana, which send up basal sprouts during old age – eventually the main trunk dies and collapses, and the sprouts form new stems. In fact, this characteristic of the genus Tilia is not isolated to North America – Tilia japonica and Tilia maximowiczii have similar qualities in Japan, and Tilia cordata within Europe most likely can achieve the same result as well.

However, such stools may not always persist – as may other features, such as veteran standards and ancient woodland indicators. Usually, the reason for such a loss in archaeological indicators is down to man’s conversion of ancient woodland to plantation (PAWS), or grazing with sheep.

Regardless, Rackahm poses the question of how exactly coppicing originated, and how did trees use this regenerating ability prior to the invention of the axe? The answer may (at least, in part) reside within the chapter entitled ‘Coppice Silviculture: From the Mesolithic to the 21st Century‘, within the publication ‘Europe’s Changing Woods and Forests: From Wildwood to Managed Landscapes‘, of which I wrote about briefly here.

Buildings

Early structures built by man, from the humble abode to the mighty cathedral, would have been constructed from wood. The size of the beams used, and the species that provided the wood, are two examples of how a landscape archaeologist may determine how the tree-lands of the local area may have looked. In the UK for example, many young oaks were harvested for single timber beams – annually, hundreds of thousands of oaks may have been harvested. This would have meant oak coppice would have been in demand, or even the harvesting entire succeeding oak stands within a woodland.

Similar means of landscape archaeology can be applied in other countries and regions of the world – Colombia, Japan, and parts of Australia (Tasmania and Queensland). Typically, the wood carpenters would head into the woods and use the smallest tree necessary to produce the exact beam needed for construction (as it was pointless harvesting large trees for timber, because the time spent dividing up the timber would have been better spent felling smaller specimens). Tree-lands were thus managed in a way that would provide for small trees year-in year-out, and larger beams and boards may well have been imported from elsewhere. In medieval England, for example, large oak boards (Baltic oak) were imported from specialist suppliers in Eastern Europe, where oaks grew slowly and reached huge sizes.

Pictures

Following the invention of photography, early pictures produced with the technology are a great way of analysing past tree-lands – often, the trees would only be in the background, with the focus of the image being something entirely different. Aerial imagery from the early twentieth century also offers a great insight into the tree-lands of the past.

Similarly, old paintings also provide for an historical account of landscapes gone by. As far back as the Bronze Age, paintings may have shown what the tree-lands may have looked like. However, until the dawn of Romanticism in the 1800s, paintings would have likely been too lacking in detail to distinguish tree species from one another.

tia4
‘Hunter Mountain, Twilight’, by Sanford Robinson Gifford, was painted in 1866. In this painting we can see how the landscape has been cleared in the foreground, and behind it sits a mix of coniferous and deciduous species. Source: Wikimedia Commons.

There is also the risk of artists cherry-picking tree-lands, with a desire to paint only single-stemmed trees being very much evident – coppice woodlands may therefore have been neglected in this medium, as may have old wood pastures. Perhaps the fact they are easier to draw lead to this bias towards single-stemmed specimens, or perhaps nobody thought coppice woodlands were worth drawing for other reasons. Ancient trees may have been a very notable focus of many artists, as a matter of fact – this is likely due to them being very emotionally evocative, and important within their own right.

Rackham notes that Japanese artists may have been the best at drawing and painting trees. From the 14th century onwards, artists on Japan could capture recognizable tree species and genera – pines were very frequently drawn and were abundantly present in pictures of woodlands, whereas their spread in Japan today is nowhere near as distinct. This indicates how the arboereal landscape of Japan, in terms of constituent species, has altered. Without such artistic reference, would this have been so readily identifiable?

Savanna and wood pasture

Scattered trees within grazed landscapes were common sights in the centuries gone by, from Europe to Africa, and from North America to South America (though the holm oak dehesas of Spain are a gorgeous example of wood pastures still in existence). These grazed landscapes may have been man-made, or even natural (as Vera suggests in his book ‘Grazing Ecology and Forest History‘). Many exist today as ex-wood pastures, and younger trees have grown up around the old worked trees (typically pollards).

dehesa
An example of one of Spain’s dehesas. In this image, we can see how cows graze beneath Quercus suber (cork oak), which are harvested for their bark. Source: Wikimedia Commons.

Savannas, on the other hand, signify the transition between forest and grassland (an ecotone, of sorts). The reason for savannas existing would have normally been because there was some driver behind the lack of ability for trees to colonise the land, be it because of human management or natural cause (altitude, for instance). In today’s age, evidence of old savannas in West Africa can be found now amongst woodland – those who worked the savanna were murdered or taken away for the slave trade, and the lack of management following their disappearance lead to woodland forming (perhaps from the seed bank within the soil, or from seed dispersed from the trees that remained).

In Australia, savannas actually cover over half the continent. This landscape originated with the Aborigines, and may show signs of old pollarding practices (either because of man taking an axe to the tree, or forest fires – the marri and jarrah eucalypts of Western Australia, when scorched by fire, sprout up in the main stem, creating a pollard-like structure over time).

Pollards and ancient trees

Whilst the giant coppice stools signified past coppicing operations, pollards signify wood pasture (as elucidated to above). Perhaps commonly undertaken to feed livestock, it was a more physically-demanding practice than coppicing, but enabled for trees to be retained as their growth was above the grazing line – this was crucial for farmers, who could essentially rear cattle and grow (some of) the fodder within the same parcel of land.

Many pollards in wood pasture are now lapsed, given the dying art of grazing (down to various reasons, which won’t be explored here). Old oak and beech pollards stand proud in the UK, as will oaks in Hungary, whilst elms and ash pollards can be found in Norway. The holm oak dehesas of Spain (and also Greece) are another fine example of (perhaps still active) pollarding operations.

vettree
This massive oak sits amongst a much younger stand of trees. It is almost certainly a relic of past land use, which would make logical sense given the entire area was once a deer park. This oak also shows signs of being an old pollard. My girlfriend (in the image) is dwarfed by the oak.

Rackham notes that whilst ancient trees can be found dotted over the landscape, they are disproportionately-clustered in areas of old wood pasture. They are not typical of ancient woodland (and thus should not be classed as indicators of the wildwood), where giant coppice stools are more frequent. Where ancient trees can be found in woodland, it is very likely that the land use changed to facilitate woodland regeneration, in place of the ancient trees growing up with existing woodland. In fact, the decline in wood pasture and savanna landscapes can be attributed to a decline in the practice of grazing over the last 200 years – the slave trade in Africa, and the push for forestry in Europe and The Americas, has lead to this.

Source: Rackham, O. (2012) The Ghosts at the Ends of the Earth: Tree-Land in Four Hemispheres. In Rotherham, I., Jones, M., & Handley, C. (eds.) Working & Walking in the Footsteps of Ghosts – Volume 1: The Wooded Landscape. UK: Wildtrack Publishing.

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Landscape archaeology and the ghosts of our worldwide arboreal heritage

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