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Harting Down - obsession with conserving man-made landscapes |
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My dislike of herbivore grazing used in conservation management has grown over the years from a disbelief at the universality of it as an approach to landscapes in the UK, and on to a disdain for the conservation professionals whose ideological dogma allows them so easily (and unthinkingly) to enforce it on every landscape in their charge (see also Conservation grazing in the introduction to No Take Zones - a maritime rewilding). It dates back eight years to a poster attached to the fence enclosing rough grassland behind the sand dunes near Bambrugh Castle on the Northumberland coast. For me, the interest of this roughish ground were the patches of tree lupins that are often found in sandy coastal grassland, but I was surprised to find the not particularly hardy tree lupin so far north. It didn’t seem to make sense to me that the advice from the then-known English Nature on this poster was to graze the grassland to reinstate and maintain the presence of other wildflowers since there weren’t any of note where this grazing was taking place. What was there, was the incursion of a few scrub and woodland species (sadly, mostly sycamore) that would be one of the targets for removal by this grazing. As I have since discovered through returning year after year to these coastal dunes, the wildflowers – such as pyramidal orchid, bloody cranesbill, restharrow, meadow rue, hounds-tongue and goats-beard - are located mostly in the low fertility, sparsely vegetated areas of the fore dunes themselves, and very few make it into the traditionally grazed pastures immediately behind. This is a question of competition with the more dominant grassland species, the grazing today trying to overcome this and extend the area that these wild plants may take root. But it is also the classic absurdity of our approach to nature conservation in situations like this. Centuries of livestock grazing of every inch of our landscapes has created the allusion of wildlife habitat that in effect only exists as an artificial environment. Our tinkering extended the range of these wildflowers, but also made their existence in this extended range dependent on our continuing management. It is interesting to note that at least the local Wildlife Trust, that manages a piece of this rough grassland behind the dunes a few miles south, acknowledges that agricultural practice is blind to the influence it has on landscapes. Their conservation grazing management plan admits that an agricultural practice of supplemental feeding of livestock over-wintered on the grassland has had the adverse effect of raising nitrogen levels in the sandy soil, and creating conditions which again are disadvantageous to the wildflowers, as it selects for other dominating species. They now have to “graze off” this higher soil fertility, but they will still be left with a predominantly agricultural landscape that will have little attraction for many of the dune wildflowers. At the heart of this is the question of what constitutes a natural landscape in the UK. Since grassland wildflowers are so highly prized, can we be sure where this natural grassland exists? Before we look at this, it is worth exploring the natural grasslands of another continent because they give us a framework within which to understand the natural forces at play. The plains and prairies of North America The grasslands of the plains and prairies of North America have a somewhat contested history because in the eastern prairies, it is sometimes difficult to separate out the significance of each of the causal factors for their existence, especially whether the impact of fire was an entirely natural phenomenon or if it was supplemented by targeted fires set by Native Americans (1, 2). Grassland will always out-compete trees in drier areas where rainfall is scant because evaporation would be greater than the water supply. The plains and prairies were dry and combustible, and thus fire was easily set off by lightening. But then fire is also thought to have been a traditional cleanup for the eastern prairies by Native Americans, clearing debris and thatch without damaging grassland potential. It is not surprising that the Native Americans are known to have observed that the tender new growth attracted buffalo the following year. Some believe the grasslands and savannahs of the eastern prairies were actually created by centuries of annual fires set by Native Americans, combined perhaps with the less physically dramatic impact of grazing by the vast herds of buffalo. Thus pockets of natural, edaphic grasslands - where rainfall was too little for tree growth - would be expanded by fire burning to the edge of forest, with each fire reaching a little further into the forest without necessarily consuming the whole of it. The evidence from the nineteenth century of forest invasion of eastern prairie grasslands after suppression of fire is perhaps supportive of this, and shows that grassland created out of woodland clearance is unlikely to be dynamically stable. Others find the evidence of wide-scale, concerted management by fire less convincing, while not necessarily disputing that it existed. It depends also at which point in archaeological time you wish to start at. Maybe it should be 25 million years ago when the Rockies arose and created drier conditions. Along with the grasslands that subsequently developed, so too did grassland animals thrive such as horses, camels and rhinos, their teeth longer than browsing animals as a result of their tendency to wear down much faster. In Pleistocene America, mammoths, sloths, pronghorn antelopes, two species of buffalo and aurochs also grazed the prairies, but all but the pronghorns and one species of buffalo were lost soon after humans and their spears crossed the Bering land bridge into North America some 13,000 years ago (3). I don’t think it is possible to generalise too much from the undoubted evidence of human management by Native Americans, especially since the plains and prairies, although occupying a common central location midway between the Rockies and the Appalachians, were distinctly different in their vegetation between the prairies to the eastern half and the plains to the western half. Moreover, since there is a dearth of information by comparison on Native American intervention with fire in the plains of the west, it is highly indicative that the edaphic conditions there were the over-riding factor in the existence of the grassland, with the west clearly suited to natural grasslands as the conditions there were insufficient to support trees other than along creeks and rivers. In addition, I have seen little evidence yet to suggest that the Native Americans sought in any concerted way to control, limit or contain the movement of buffalo other than through their selective burning in the east that might have tended to cause the animals to conveniently over-winter in unburned areas of prairie. Thus any effect of their herbivorous actions was fundamentally a natural action in the trophic cascade rather than an anthropogenic or human-controlled action, which is the case for farming and now the conservation grazing with enclosed livestock or ponies in Britain. The difference in grassland species between the plains and prairies is shown by tallgrass prairies and associated forbs being found to the east, and shortgrass prairies and associated forbs in the plains to the west. And they were fringed by different open canopy wooded landscapes: the northern aspen parkland and southern ponderosa savannah bordering the plains, and northern and southern oak savannah bordering the prairies. The floristic and vegetative divides are thus dependent on whether it is relatively wet or dry (east versus west) and whether the fiercest season is a cold winter or a hot summer (north versus south). These are the edaphic conditions – the natural, biotic conditions – that influence whether the grassland is dynamically stable and thus natural. Sad to say the slaughtering out of the buffalo population in the nineteenth century just for its skins was also accompanied by the destruction of the prairies and the plains as the “west” was opened up to migration. The native tallgrass prairies represented rich opportunities to farmers fresh from Europe, and so they were soon cleared, ploughed and farmed, destroying a prairie soil structure where the root layer could reach up to seven meters deep. The estimate is that only 1% of tallgrass prairie remains now in scattered fragments in Ohio and Kentucky. The shortgrass prairies of the Great Plains were naturally dry, and were ideal for ranching rather than farming, but they too were ploughed and fenced, in line with the policy of the US government to support farming. It was this policy that resulted in the disaster of the dust bowl during the depression of the 1930’s when farm topsoil blew away in cultivated land and rangeland was grazed down to bare earth by livestock. I suppose we must be thankful that the buffalo were not around to see all this happen. Where is the natural grassland in the UK? The common understanding is that the introduction of agriculture into the UK some 5000 years ago led to the wholesale clearance of woodland because grass does not grow in the shade of woodland. Thus the majority of our grassland is an artificial environment, maintained by livestock grazing, which would revert to woodland given the chance. So where did the grassland wildflowers grow before the woodlands were cleared, and do these natural grasslands or grassland-like habitats still exist? For a number of years now, I have examined the vegetation cover on the cliff-tops and slopes around the coastal margins of the UK, and I think it is there that this natural grassland still exists, and it would have been one of the margins – along with the occasional openings in woodland, the montane margins and possibly wetland areas - where the grassland wildflowers would have been found originally before the woodland clearance. It comes down to looking for where the environmental/edaphic factors are such that the growth of shrubs and trees is inhibited, with the grassland species winning out. The coastline of the Pembrokeshire National Park, brought to life by John Barrett, its most able interpreter (4), provides plenty of opportunity to observe this because of the range of conditions of extreme exposure that it faces, and because the land of the long distance path that traces most of the coastline is for the most part separated off from the farm fields beyond the cliff edge. Barrett talks of the twists and turns of the Pembrokeshire coast so that some stretches feel the full fury of winter gales that occur on up to 32 days a year (with gusts up to 90mph, and calm on only 38 days a year) and are soaked by salt spray carried up from the waves, while other lengths are tucked around corners and are fully sheltered from this buffeting. The differences don’t stop there as both exposed and sheltered lengths may be in full sunshine or deep shade for part or most of the day. Geomorphology (landscape) and geology also vary from sheer cliffs to gentle slopes, with varying soils derived from acid or basic rock, from glacial material, or mixes. Barrett notes that all these variables occur in any combination, and it is this set of edaphic factors that explains the exceptional mix and splendour of the coastal wildflowers. These coastal wildflowers thrive because the edaphic conditions maintain areas of open, low or little vegetation. There are a few areas where trees cling on, the scrub oaks that overhang the north facing length of coast known as Goultrop Roads, just below Little Haven, may represent a remnant of what the wooded areas of the more sheltered coast once were. But trees have it hard from the drying and cooling effects of wind. Gales in spring are likely to “burn” and destroy the opening new shoots on the windward side of trees so that they become misshapen by die-back and appear to bend away from the wind. Clever trees, like the scrub oaks there, get around this to some extent by growing flatter to the slope like an octopus, rather than upwards, so reducing their wind profile. With the greater exposure to wind away from the relatively more sheltered areas, blackthorn nurture the last surviving trees and themselves tail off into a thicket of brambles in which gorse is commoner as the last tree finally disappears. Exposed to the increasing forces of the wind, scrubby species diminish - blackthorn is wind pruned so much that it seems to be layered to the shape of the land and then disappears leaving only some heather and prostrate broom on south facing cliff slopes. But it is there, in full sun and high wind where the maritime grassland habitat is found, and where the wildflowers that are resilient in the face of these extremes of exposure are magnificent. Inland from this treasury of natural influence and effect along the Pembrokeshire coast, the major shaping factor on the landscape very quickly becomes agriculture with its livestock grazing and arable farming. But there are some headlands on the Pembrokeshire coast owned by the National Trust – such as St. David’s Head and the Deer Park on the Marloes Peninsula - that are not enforced to produce an income from farming, and where you might expect that the Trust would be content to allow natural forces to shape the landscape. However, the legacy of their historical farming use, coupled with a slavish adherence to contemporary conservation dogma, results in the Trust overgrazing these headlands with mountain ponies in the vain hope of extending the maritime cliff-top grassland and heath inland from the coastal cliff edges (see National Trust, Pembrokeshire in Heroes and Villains). Clearing through Harting Down It may just be my opinion that the conservation measures of the National Trust at these locations in Pembrokeshire are suspect, but elsewhere the Trust is embroiled in a public dispute over conservation of another of their landholdings. The Trust acquired Harting Down in West Sussex some 15 years ago and it is said that their management of this chalkland site was initially sensitive, with a light touch used in freeing up some of the juniper bushes by the cutting back of scrub so that the traditional sheep grazing of the chalklands could then keep them open. But Harting Down is not all chalk grassland and there are important bands of yew and deciduous woodland on the chalk escarpments that are a regular and highly appreciated feature of the South Downs chalk landscape that stretches from Winchester to Eastbourne (5). Over the years, the valley bottoms on Harting Down – Whitcombe Bottom and Bramshott Bottom - had begun to develop a rich mixture of natural tree regeneration, along with the shrubs and grassland. This really appeals to local walkers as a unique landscape with increasing wildland character. But then the Trust brought in commercial contractors to completely clear through 20-30 acre blocks of this landscape mosaic, and with also widespread use of herbicide spray. The fear is that this gross approach is the factor that has led to the loss of the local nightingale population. The presence of a volunteer work party last March on Harting Down moved local people to action when 30 signed a letter to Fiona Reynolds, Director-General of the Trust, that got the the prospect of a further clearance stopped. Another 40 signatures were collected in just a few days. At issue here is nature conservation’s apparent obsession with the species of calcareous grassland above any other landscape content. The Trust’s high-handed management approach is backed by the statutory agencies, local societies and single interest groups because they are locked into the dogma that values the wildflower and insect distribution in an artificial landscape. The usual designations are in place to support the conservation management such that Harting Down is a SSSI (and a Local Nature Reserve) in an Area of Outstanding Natural Beauty, and could soon be part of the new South Downs National Park. A large proportion of Harting Down is also a registered commons, giving open access to the public but also a lack of fencing that enhances the wildland experience, although be aware that the Trust find the bar on fencing from commons registration an inconvenience to their implementation of conservation grazing (6).
You can be sure that the Trust will justify its management by
referring to the SSSI designation for calcareous grassland, and that the
plea from local people for management that is sympathetic to, and retains
that wildland character, is likely to fall on deaf ears. I still await a
response from the Trust’s Head of Conservation on what
is the
Trust's aim for the landscape of Harting Down, and how it hopes to achieve
it. But I have been told that the local and regional managers are moving
on, and that a new management plan is in the offing. It is perhaps too
late now, but that management plan should take note of a paper from 1976
that puts this obsession with calcareous grassland into context. Peter
Grubb, now an Emeritus Professor in the Department of Plant Sciences at
Cambridge, wrote (7): Grubb goes on to identify four ecologically distinct groups of annuals, biennials, and some perennials, found in chalk grassland whose capacity to react to changing environments or to tolerate extreme conditions indicates the nature of the edaphic, natural habitats from which they were originally recruited, such as woodland edges at the margins of cliffs, cliffs in lowland and montane areas, coastal sand-dunes, what woodland openings there were, and well drained micro-sites within the marshes and fens of the lowlands where tree growth was poor. Thus the shrub and tree species would appear to have a greater claim to a natural, edaphic presence on Harting Down than does the chalkland grasses and wildflowers there. Harting Down is a microcosm of the current difficult issues of the mismatch between mainstream nature conservation and the gradually more sophisticated appreciation by ordinary people of an increasing wildland experience where natural, edaphic forces are allowed to reign. It thus joins an ever-growing list of where local people have objected to heavy handed conservation management: at Odiham Common, St Catherine’s Hill, Ashdown Forest, Chobham Common, Dorset Heathland, and Blacka Moor. Often it is the dramatic clearance in an effort to turn back the landscape clock, of the shrubs and secondary woodland that were regaining these artificial landscapes, that signifies the start of the heavy handed approach. Couple that with often the new imposition of fencing and the extension of livestock grazing, which cuts across the open access that people have come to enjoy, then it is not surprising that they have been moved to protest. These actions deny local people the most authentic experience of wildland that we have in the UK since it represents probably the nearest we can get to wild nature’s choice of land coverage, the developing natural wildwood. All of these local people ask for a considerably less rigid approach to nature conservation, and for conservation professionals to become much smarter in using a more sensitive and selective approach to land management. If the barrier to that is landscape designation in the UK then the legislation has to be changed, especially since it is now increasingly recognised in the EU that there is a conflict between Natura 2000 management requirements and wildland, mainly because the provisions of the Habitats Directive have been too tightly interpreted in member states. Thus more attention must be paid by conservation professionals to landscape issues over and above species, and to the need for a mixed habitat approach. Mark Fisher, 4 November 2007 (1) The Pristine Myth: The Landscape of the Americas in 1492, William M. Denevan (1992) Annals of the Association of American Geographers, 82:369-85 (2) Gardening with prairie plants, Sally Wasowski (2002) U. Minnesota Press ISBN 0-8166-3087-9
(3)
Donlan, J.C. (2007)
Restoring
America’s Big Wild Animals.
Scientific American
June 2007, 70-77 (4) The Pembrokeshire Coastal Path, John H Barrett (1974) HMSO ISBN 011 7003360
(5)
Wooded
Chalk Escarpment, Sussex Downs Landscape Assessment, Sussex Downs
Conservation Board 2001 (6) Grazing for Nature Conservation on National Trust Land, Matthew Oates, Adviser on Nature Conservation, National Trust, November 1998
(7) Grubb,
P. J.
(1976)
A
theoretical background to the conservation of ecologically distinct groups
of annuals and biennials in the chalk grassland ecosystem.
Biological
Conservation, 10, 53-76 url:www.self-willed-land.org.uk/articles/harting_down.htm www.self-willed-land.org.uk mark.fisher@self-willed-land.org.uk |