Sunday, November 10, 2019

The Decline in the Ecological Quality of the woodland, Heathland and Wetland Areas in the New Forest

The New Forest, a landscape enjoyed by many as a wonderful break from the bustle of city life, An abundance of species rich habitats, a place of solitude, as open space to be valued and conserved for both present and future generations. To many the New forest may seem an unchanging mosaic of forest, heath and wetland interlocked with small rural settlements whose traditional character seem almost timeless. However beneath this uniquely picturesque landscape lies an environment which is both complex and forever changing, a landscape which through history, has been heavily influenced by man and his activities. The precise role of man and the influence he is having upon the natural environment often creates a complex set of management issues. These issues embody not only concerns for the environment but often have economic implications for the wider community. The New Forest is a good example of this; it has many conflicting uses and hence requires management. Figure two displays this range of habitats. Habitat Area/ha Heathland/Acid Grassland 11740 Valley Mires and Wet Heaths 238 Unenclosed Deciduous Woodland 4049 Statutory Silvicultural Enclosures 8100 Unenclosable (open to exercise of common rights) 19028 Fig2: The proportions of different habitats It is the largest area of unsown vegetation in lowland Britain. Each habitat is affected differently by different uses, which in the past may have caused a decline in their ecological quality, it is both these uses and the management strategies associated with them that will be the focus of this article. History of Landuse and Management The forest became appointed to the crown as Royal Forest nine hundred years ago, it was used as a reservation for deer and domestic stock. This grazing and browsing limited the regeneration of trees and shrubs. It is currently under the management of the Forestry Commission as detailed in the Forestry and New Forest acts. The Forestry Commission is responsible for the ancient and ornamental woodlands and their timber enclosures this is refered to as the ‘Crown Land'. They are required to give priority to conservation of the forests traditional character. They practice forestry in the Silvicultural Enclosures and have a responsibility for managing the unenclosed forest. The New Forest Heritage area will be referred to as the ‘New Forest'. The common land within the perambulation will be referred to as the ‘Open Forest'. Privately owned and fenced lands will be refered to as ‘Enclosed lands'. Fig 1:Dockens area Fig 3: The New Forest Heritage Area Ten Verderers became responsible for management of communal animals depastured in open forest. They regulated the right of the common promoting the improvement of grazing for the commoners. However these days there are strict guidelines which commoners must adhere to, to try to ensure the retention and sometimes improvement of the landscape quality. In July 1994 the government recognised the New Forest as a unique area giving it similar protection as a national park. It also possesses other designations, it is a SSSI although this offers protection from development it offers little in the way of conservation. In 1996 the New Forest Committee published a management plan entitled ‘A strategy for the New Forest' its individual aims and strategies will be assessed throughout this article. The Committee represents the principal central and local government organisations in the forest who include Countryside Commission English Nature Forestry Commission Hampshire County Council New Forest District Council Verderers of the New Forest Salisbury District Council Test Valley Borough Council Wiltshire County Council (as Observers) Country Landowners' Association National Farmers' Union (as Observers) The development of a management strategy like The New Forest Strategy is important as it recognises the interests of all groups concerned, although the participation of so many organisations that often have conflicting interests may often make management difficult. Today most of the New Forest exists as a pastoral economy based on the exercise of common rights and grazing. The community of farmers made up of between three to four hundred commoners depend upon this for their livelihoods hence the combination of this and conservation makes management more difficult. It is thought that grazing has had a greater effect on vegetation than peat cutting and deforestation, indeed it is thought the landscape has evolved to its present state through the effects of grazing. In each area ecological quality is affected differently by a variety of different uses, so it will be necessary to assess the decline of each one in turn. Woodland Although there are both Silvicultural enclosures and ancient unenclosed deciduous woodland it is the later that possess the most nature conservation value. The silvicultural enclosures though contain approximately 40% of Oak and Beech some containing unmodified former pasture woodland. Because these enclosures have been less grazed than the unenclosed woodland contain many rare plants including bastard balm and the lungwort. These enclosures also contain large populations of predatory birds such as Buzzards and sparrow hawks. Fig 4: Native trees during flood Oak and Beech dominate the unenclosed deciduous woodland, Oaks being more dominant on heavier soils varying in proportion. Under this canopy Holly dominates along with maple and hawthorn. Older oaks contain the richest woodland lichen flora in Lowland Europe while insectivorous birds colonise decaying timber. This area is open to the exercise of common rights and has been for many years, indeed this habitat is Semi-natural, and exists as a Plagioclimax. There has been much research to determine whether this grazing of domestic stock has caused an ecological decline in these forests The animals can be very selective hence the less edible plants may become the most dominant. As a result much research has been undertaken to assess the effects of grazing on woodland. This is in many ways an attempt to determine the level of grazing necessary to prevent further damage to the environment and slow down any ecological decline associated with it. During 1960 Dr George Peterken established ‘The age structure of the enclosed woodlands was related to fluctuations of large herbivores since at least the eighteenth century'. He also found that the most recent periods of regeneration of woodland were 1860-1910 and 1930-1945. The first of these followed the killing of most of the deer population after the order of the deer conservation act in 1851, while the second was due to a slow market and a corresponding reduction in stocks. This had a dramatic effect on the landscape and remains proof of the limiting effect of grazing both on woodland quality and area, as it followed the generation of new trees in adjacent areas. However nowadays commoning has been more intensive and there have been too many invertebrates to allow such natural regeneration. Clearly Herbivores influence species composition and age structure of woods so much so that in the New Forest today elm lime and hazel no longer make up the canopy of the majority of woodland. Research by Prof. Barber of Southampton Univ. has highlighted these reductions in diversity. His pollen diagrams show that elm and lime die out suddenly. He attributes this to them being felled and failing to regenerate. He has also documented a decline in hazel and its disappearance recently. Documentary evidence from 16th and 17th centuries shows hazel to be common. All of this evidence shows a slow increase in browse resistant holly, a decline in ecological quality, which can only be attributed to selective grazing. In comparing this to private forest of similar edaphic quality that has mainly been coppiced we find hazel still abundant along with a rich herb layer. This is in comparison to the sparse herb layer of the grazed area, which comprises of around a poor thirty species. The ungrazed area also contains many lichens and deadwood invertebrates, hence a wide variety and species richness. Management of Woodland The New Forest Committee in their Strategy for the New Forest recognises that ‘Grazing in open forest by sheep and cattle has a strong influence on the age regeneration and species type of the vegetation' They also recognise that the numbers and proportions of ponies to cattle have a significant effect on the ecology of the forest. It refers to ‘The Lingworth Report' on grazing. It suggests that pony and cattle premium schemes and marking fees should be used as a mechanism for influencing numbers turned out. Recent research however has shown that social and cultural factors play a greater role in decision making. The report recognises that commoning is poor source of income for commoners and that restrictions on landuse and stock numbers may have profound effects on their livelihoods and the local economy. The Forestry commissions policy is ‘to conserve woodland as an essential component of the traditional character of the forest'. Part of the ‘New Forest review' recommends that ‘The maximum feasible area of native area of broardleaved component should be grown on the longest feasible rotations, and the possibility of restoring some conifer plantations to broardleave should be investigated'. Such recommendations are encouraging for conservation however the actual implementation may be more difficult to put into practice, while the affects of any recent measures are too early to assess. Unfortunately it is difficult for the Forestry Commission to assess the extent of deterioration or have any control over development in the privately owned forests. This is identified in the ‘Strategy for the New Forest', it recognises ‘Changes in the design and siting of new planting, changes in management practices and species composition and loss of hedgerows all have important implications for the forest as a whole' Indeed comparison of the area today to that recorded in the New Forest by English Nature during 1994 shows a reduction in quality of the landscape. It identified 94 sites supporting ancient woodland amounting to 2330ha in privately owned areas. The Report identifies that 37% of ancient woodland from these areas has now been replanted with conifers. Heathlands These are the result of mans activities particularly burning over the last three thousand years and are hence regarded as Semi-natural. Heathlands similar to woodlands have been grazed throughout history. Some heaths were part of the commoning system these are outside the Crown lands and have been enclosed since the 19th Century. Some heath is unenclosed on higher ground. The fringes of the forest in the west have extensive heaths. The heaths inside the perambulation have become degraded through recreational use and gravel extraction, this has contributed to much fragmentation and a reduction in this habitat. Scrub encroachment has become a particular problem and has led to a reduction in bio-diversity through competition. Grazing by Ponies is believed to have led to the rapid decline in populations of Dwarf Gorse an important component of the heathland. The evidence is indicating that grassland is expanding while heathland contracts and this is leading to a decline in the ecological quality of the forest. It is thought and shown by observation that this is apparent where there is intensive grazing and trampling. In 1973 Dr Colin Tubbs showed that areas of heath that had been burnt failed to regenerate due to the grazing pressure. Heathlands support birds like the Dartford Warbler, which in the New Forest has been put under threat by grazing. In 1974 Colin Bibby conducted a national survey of Dartford Warbler populations he concluded that burning and heavy grazing had reduced the birds habitat namely the heathlands, and had hence he attributed a decline in populations of Dartford Warbler to this decline in habitat. It is thought by entomologists that insects particularly butterflies were more frequently sited during the 1930's. However this is difficult to place certainty on as much of the data is unreliable. They have found that species such as High Brown, Dark Green, Pearl Bordered and many other rare species, which were abundant, are now confined to local areas. During the 1930's there was less grazing, both this and the higher diversity and this can be said is proof of this ecological decline. Colin Tubbs has expressed concern over buzzard populations who rely on heathlands as their habitat. Competition with large vertebrates is causing them to decline through limiting the number of small ground vertebrates such as rabbits by over grazing. This is the underlying Hypothesis surrounding much of Colin Tubbs work in this area. He established in 1973 that there was a large fall in buzzard production with only one out of six pairs known to rear young since then the number of successful pairs has stayed below the levels during the 1960's. This followed a large fall in the number of small rodents counted in southern England during 1970. It is difficult to place much reliability on this data. The grazing by ponies continues to be intensive and remain so unless the Forestry Commission takes action. Actions such as the erecting of fences are of little use, as Ponies seem to have a remarkable ability to leap over fences. The Forestry Commission has had to dedicate time to the removal of Ponies and this can often be very costly. Management Of Heathlands The Heathlands are managed by the Forestry Commission, during 1986 the New Forest Review group recommended that some conifer or open woods should be returned to open heathland to reduce there decline, purely in the interests of conservation. The Forestry Commission has already started this holistic approach away from the economic needs of forestry to those of conservation. Many of the proposals outlined in the ‘Strategy for the New Forest' aims to: ‘work with landowners to conserve and extend heathland reinstating traditional management where possible' RA3.73b.8. This will be possibly hard to implement, as the economic needs of commoners may be difficult to overcome in the pursuit of conservation. This may only be possible through the adoption of joint marketing of Forest animals and produce to offset the financial implications of this proposal. This is outlined in section 4.1.6 of the report. The Forestry Commission is responsible for the management of the majority of these areas and there is a tendency for their economic implications to override those of conservation. Management also aims to: ‘Raise awareness of the ecological importance of heathland and encourage local support for its conservation' [RA3.7c]. This is important as raising awareness of the public can lead to involvement through voluntary organisations which can lead to a reduction in expenditure by government and an increase in the amount of positive management for conservation. Although this is hard to implement as it often involves some expensive form of interpretative media. All these policies aim to restore and recreate heathland, although the effects of these actions to the problems already discussed are not yet visible. Wetland's The New Forest possesses ninety valley mires of which there are only 120 in the whole of Europe, these have high conservation importance. Draining during the 1950's and 60's has lead to a reduction in the ecological quality of these environments. Restoration of these areas is important as some pockets contain unique flora and flora, an immense biological richness. They provide both grazing and water for forest animals. Rare species include slender cotton grass (Eriophorum gracile), bog orchid (Hammarabga paludose) which are very rare in Southern England. The Forestry Commission previously had a duty to drain many mires in an effort to fulfil the statutory obligations of ‘The New Forest Act of 1949'. Unfortunately it is only recently that the importance of this habitat ecologically has become realised. It is now part of the ‘New Forest special area of conservation' and is both a ‘RAMSAR' wetland and a ‘SSSI'. The most important Mires are located in the Crown lands. The wetlands also include many rivers and their floodplains, while there are historic water meadows and fifty ponds, these also posses high bio-diversity and require management. Many of the streams are rare due to there acid nature hence they support rare species. There has been a reduction in the ecological quality of these areas by modifying or straitening of the marine channels. Low levels in the Rivers and streams have been attributed to a lowering of the water table by boreholes and streams. Management of Wetlands In relation to rivers and streams, the ‘Environment Agency' has developed a ‘Catchment management plan' for the New Forest. Which is concerned with the future management of these areas. The recommended actions associated with this management I am unaware of. In relation to mires the Strategy aims to: ‘Restore and enhance damaged valley mires' [RA3.8b]0 This involves techniques to slow the flow of water restoring levels of water to how they were before drainage. This is achieved by installing small dams along small ditches in an attempt to drain the mire. It tries to mimic natural channel blocking; it is hoped that this will halt headwald erosion. Deep channels have developed in some places, which are a hazard to livestock and damaging to the mire. ‘The Forestry Commission' has been aiming to infill these with local material to hope that they blend in with surrounding heathland vegetation. Again many of these important areas of conservation occur in the Crown land i.e.- Mires. In one of its recommended actions the Forestry Commission work with land managers and advise them in areas where conservation may not be the land managers highest priority. In Relation to this the strategy aims to: ‘Identify wetland features important to the traditional character of the New Forest and work with landowners/land managers to secure their conservation.' [RA3.8a], see also RA3.3c0 It is clear now that the New possess a very complex range of management issues and that successful management will require great co-operation between all groups who have an interest for one reason or another in the New Forest.

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