THE NEW FOREST an Ecological History
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THE NEW FOREST An Ecological History By Colin R. Tubbs First published: Newton Abbot; David & Charles 1668 This computer file resulted from a discussion between Colin Tubbs, Denis Bellamy, of the National Museum of Wales, and Emma Wrigglesworth of the New Forest Committee. The subject was the need to produce interactive computer resources for schools in the New Forest area. Colin agreed to the use of the text of his book, The New Forest; An ecological history for this purpose. The aim was to for it to be formatted as a self-indexing programme, and made freely available within the Schools in Communities Agenda 21 Network (SCAN) to encourage teachers to use the New Forest as a cross-curricular exemplar of environmental management. The idea was also that it should be cross-referenced with hypertext to other relevant materials, particularly with regard to updating. This version is the first one to be mounted on 'Acrobat' software- it contains all the text but the Tables, and connections to primary references are not complete. Contents CONTENTS INTRODUCTION MAN AND THE PHYSICAL BACKGROUND THE PATTERN OF SETTLEMENT MAN, SOIL AND VEGETATION THE ROYAL FOREST MODERN ADMINISTRATION AGRICULTURAL ECONOMY RECENT ECOLOGICAL HISTORY I RECENT ECOLOGICAL HISTORY—II THE STATUTORY INCLOSURES GRASSLAND, BOG AND HEATH THE LARGER VERTEBRATES - LOSSES AND GAINS FEATURES OF THE MODERN FAUNA THE FUTURE ACKNOWLEGEMENTS REFERENCES Introduction It is perhaps a matter for surprise that the New Forest, with its peculiar institutions and agriculture, its outstanding biological interest and its ease of access, has escaped the close attention of little more than a handful of historians and field scientists in recent years. Despite its ready accessibility it has comparatively seldom been used as a teaching arena. Its unenclosed woodlands and heathlands, however, today comprise the largest single unit of 'seminatural' or 'unsown' vegetation remaining in the Lowland zone of Britain, and for this reason it is unlikely that the neglect of the past will be long perpetuated. As urban and industrial development and agricultural reclamation continue to reduce and fragment the ground available elsewhere for biological, archaeological and other field studies, so attention is likely to become focused more closely on the Forest. Such a trend is already discernible. Although the area has long been recognised as something very special, the local literature in most fields of study remains thin and more often than not plagiaristic, 'folksy', or both. The first purpose of this book, therefore, is to provide an accurate historical and ecological backcloth to future research, and to present it in a manner which will also be found acceptable to the layman. The hypothesis that the landscape of Britain has arisen largely from Nature's responses to human activity would scarcely be seriously questioned. It would appear, therefore, that the history of human land use, management and exploitation, and the economic factors governing them, forms a coherent framework within which to describe the development of the range of habitats which comprise the landscape; for arriving at conclusions about the parts currently played by biotic and anthropogenic factors in the dynamics of habitats; for focusing the closest attention on the economic structure of agricultural and other practices from which such factors arise; and for arriving at conclusions about the history, present status and future of individual species of our fauna and flora. Habitats are usually in the process of change, even though such changes may be exceedingly slow and not readily demonstrable visually. The previous history of change is thus important in discerning what processes are at work at the present time, and in deciding precisely how to manage or control them. The first assumption of this book, therefore, is that most of the archaeological, historical and biological information relating to the Forest can be most usefully organised under the heading of ecological history. I am only too conscious that this account of the Forest's ecological history tends on close examination to reveal almost as many cracks as there is wall. This is perhaps inevitable when so broad a framework is chosen for the study of so comparatively small an area. I can only hope that sufficient attention has been drawn to the cracks to prompt further exploration. Chapter 1 Man and the physical background In Britain, and indeed over much if not most of the world, the present vegetation and soils have developed from the interaction of geological and geomorphological factors, climate and the activities of man. In considering the ecological history of the New Forest-and indeed that of any part of this country-it is apparent that man has been the most potent force in the development of the present scene. Since Mesolithic times he has striven with increasing vigour to adapt his environment to his progressively more complex and sophisticated social and economic life. His activities have, at the same time, been constrained by the physical limitations of his environment and thus, his attempts to adapt Nature to his purpose have not always met with conspicuous success. In areas like the New Forest the base-poor quality of the parent materials from which the soils are derived proved a severe restraint to prolonged and intensive agriculture in early times. Man's early activities were largely responsible for further deterioration in soil potential and the onset of widespread heathland conditions. In later times, the peculiar legal status of the area as Royal Forest precluded the more intensive use which would otherwise have been possible with successive agricultural innovations. The purpose in this first chapter is to elaborate upon the physical background of the Forest area and to then outline the interactions between physical elements and the activities of man. I Geologically, the New Forest occupies a central position on the Eocene and Oligocene strata lying in the downfold of the chalk known as the Hampshire Basin. These strata-mainly soft sands and clays-are of sedimentary origin and were laid down in a series of cycles of sedimentation during the Tertiary Era. The geological record of this period is complex but, in outline, alternate risings and sinkings in the land surface appear to have taken place during which series of marine, estuarine and fluvatile deposits were left as the sea first invaded the land and later retracted, leaving the work of deposition and re-distribution to rivers and their estuaries or deltas. Each phase of deposition left different types of sediment, the marine, estuarine or fluvatile origins of which may be most readily determined from their associated fossil remains of contemporary forms of life. The present site of the Hampshire Basin during this long period of geographical flux formed part of an extensive area of deposition known as the Anglo-Franco Belgian Basin. Subsequent folding of the earth's surface, together with widespread denudation, however, have left only relicts of the consolidated Tertiary formations, mainly in hollows represented in Britain today by the Hampshire Basin and Thames Basin. Because of the dip in the strata produced by folding, the older deposits are now exposed at the margins of the Basins, whilst the exposures become progressively younger towards their centres. In the New Forest sector of the Hampshire Basin, the sequence runs more simply from the oldest in the north to the youngest in the south. Of the two earliest Eocene formations, the Reading Beds were mainly of freshwater origin and the immediately overlying London Clays appear to be entirely of marine origin. Both strata are now exposed as narrow belts (the London Clay about twice the width of the Reading Beds) at the margin of the chalk. Neither are now represented in the New Forest, although they outcrop immediately to its north. Next follow the Bagshot Beds, exposed in the extreme north of the New Forest as poor sands of fluvatile origin; and then the Bracklesham Beds, partly of marine and partly of fluvatile origin, the former yielding some fossil-rich and relatively basenriched glauconitic clays. The Barton Sands and Barton Clays follow next in the sequence, and are largely of marine origin. The Bracklesham and Barton Beds are exposed over a broad, central belt of the Forest. Overlying the Eocene deposits are those of the succeeding Oligocene period. Of the four divisions recognised-the Headon, Osborne, Bembridge and Hamstead Beds-only the Headon Beds are represented in the New Forest. The Headon Beds exhibit great variety of texture and origin and appear to be the relicts of very varied contemporary conditions-freshwater lakes, brackish lagoons, estuaries and shallow seas. They occur mainly as loams, clays and clay marls-the last formerly of great agricultural importance in the area in historical times-and extend across the south of the Forest, although large tracts are covered by spreads of gravel deposited long after the Tertiary Era. Superficial deposits of gravel, consisting of subangular flints and flint pebble, overlay large areas of the solid formations in the New Forest, forming caps of irregular but comparatively inconsiderable thickness over plateaux at heights varying from around 400 ft to less than 100 ft. The higher of these Plateau Gravels pre-date the lower-lying spreads (such as those overlying the Headon Beds), and the latter, like the Valley Gravels which occur as terraces along existing river valleys (such as those of the Test and Avon) were probably derived from the destruction of the higher series. Thus the higher level gravels in the New Forest have a fragmentary distribution along ridges between which erosion has re-exposed the solid strata to produce wide valleys. The Plateau Gravels almost certainly date from the Pleistocene, during which much of Britain was undergoing glaciation, and the rivers which produced them must have been of immensely greater volume than those of today.