CHANGES IN VEGETATION AND FLORA IN THE LAST 1,000 YEARS

19 1000 YEARS OF NATURAL HISTORY

Trans. Suffolk Nat. Soc. 36 (2000)

CHANGES IN VEGETATION AND FLORA IN THE LAST 1,000 YEARS

FRANCIS ROSE

“1,000 years” takes us back to late Saxon times, before the Norman Conquest. By the year 1000, much had changed in our vegetation and flora, especially in the lowlands of England. The Neolithic, Bronze and Iron Ages periods had also much modified the original vegetation of the British Isles, and the Roman Occupation of over 400 years did even more to our vegetation. By A.D. 1001, little can have been left of Oliver Rackham’s “Wild Wood” in the British lowlands: Rackham discusses these profound changes in his various lowlands books. I shall confine my remarks largely to the lowlands, with emphasis on eastern and south-eastern England where the landscape had been quite transformed long before A.D. 1001.

However, the remaining semi-natural vegetation of most of lowland England, although very different from that of the period before intensive settlements, agriculture and pastoralism, was profoundly different from that of today.

Coastal vegetation Until recently, the coastal vegetation of England was the least altered by man: only in the last 100 years have profound changes (due largely to the development of the seaside holiday industry) taken place. Even today, much of the East Anglian coastal vegetation - especially the great shingle beaches of Suffolk and the dune and salt marsh coast of North Norfolk remains remarkably unaltered due to human effects, though natural processes of erosion have produced much change along the East Anglian coast, and locally the coastline has even accreted, forming new land areas (e.g. Dungeness beaches in Kent). However, the south coast from Kent to eastern Dorset, has been profoundly changed by residential and holiday development, especially in its lowland coast areas.

The plant communities characteristic of sand dunes and beaches there are now limited (more or less strictly) to nature reserves. Until the 1930s much of our southern coastline was an undisturbed paradise for coastal plants and birds. The chalk cliffs have remained more or less intact (apart from places like Peacehaven in Sussex) because the topography has made it difficult to develop them. Even on the cliffs however, visitor pressure can be a destructive factor, though this can be exaggerated, moderate trampling in the absence of grazing may do more good than harm.

Chalk Downs The Chalk Downs, until well into the 19th century, covered large areas of countryside in southern and eastern England, as we can see from the first editions of the Ordinance Survey Maps. From the writings of C. C. Babington (1860), we know that until the middle of the 19th century, most of the chalklands of Cambridgeshire, for example, were open sheep-walks, with fine short turf. Here plants such as the Pasque Flower, Pulsatilla vulgaris, were abundant and widespread. Many other species, characteristic of fescue or


Suffolk Natural History, Vol. 36 20

Upright Brome grassland could be found. By the close of the 19th century nearly all of this grassland had gone, leaving only small “oases” of this type of vegetation, which seems to have first developed in Neolithic times or earlier.

The Sussex Downs remained largely as open grassland until the middle of World War II - I am old enough to remember this situation myself, both North of Brighton and in the area of West Midhurst. Here the areas too steep to plough have largely colonised with scrub of low botanical value, or even secondary woodland, or have been “improved” by reseeding or the heavy use of fertilisers, which destroy biodiversity. Again, fortunately, a few areas remain as well managed Nature Reserves, or at least S.S.S.I.s. With the collapse of the traditional rural husbandry, these changes were inevitable, one must emphasise however, that in recent decades, neglect has been the enemy of biodiversity.

Breckland The Breckland of East Anglia seems since c.1000 A. D. to have been largely open grassland, with no doubt a rich flora either like that of chalk grassland (CG2) etc. or in the deeper sandy superficial drift, grass heath or heathland. Where soils were developed on leached superficial sands, a range of types of acid grassland (NVC U1 or U2) or Calluna heathlands. In Norman times and onwards, much or the Breckland grasslands and heaths became rabbit warrens; rabbits became a most important source of food. With phases of intermittent cultivation locally, when demands for cereal food became greater, this situation persisted until the late 19th century or even up to World War I. Old records tell us that the Great Bustard was frequent here, and we have enough records of plants from the 17th and 18th centuries to know what the vegetation was like. A. S. Watt of Cambridge University (1940 etc.) produced splendid reports on the Breckland vegetation patterns, as they were earlier in the 20th century.

As on the chalklands elsewhere, all except a few limited areas are now under intensive modern agriculture. As with similar other communities even the “protected” areas or reserves are now suffering from drift of fertilisers on the wind from farmed areas, which appear (as in Denmark) to be damaging the rich Cladonia and other lichen communities.

Heathlands A similar story applies to formerly vast heathland area of East Anglia in the Sandlings of East Suffolk, North and N.W. Norfolk and the S.E. Midlands. A similar situation applies also south of the Thames in Hampshire, Sussex, Surrey and Kent, on the Lower Greensand and the Tertiary sands and gravels. South of the Thames however, changes have been less devastating due to the unglaciated, more hilly topography, and more rich Calluna-heath, with more wet-heath areas remaining. However, even in these areas the heaths are now largely deteriorating. This has been the case especially since the huge decline in rabbit populations since the myxomatosis epidemic that first hit Britain in 1951. Many areas, still open heath into the early 1960s, have now become closed Birch or Pine woodland, or have becomes “seas” of tall bracken. When sheep grazing largely disappeared from our southern heaths in the early 20th



century, the rabbit population (originally escaped from earlier organised rabbit warren) kept the heaths (and much of the chalk grasslands) short and open until the 1960s. Since then the changes have been dramatic. Fortunately various conservation bodies have in more recent years, made great efforts to keep our heaths - or some of them - open, and to restore others by clearing the invasive scrubs and woodland but it is a huge task. The only real, permanent remedy is the re-introduction of the traditional grazing, by sheep, cattle, or sometimes horses. But this is a huge task, requiring much expense and labour at least initially, and after that, skilled work by stockmen to maintain the grazing. Unfortunately the re-introduction of grazing in th modern world requires fencing of the heaths, largely because of the motor car. Before the days of motor vehicles, it did not matter very much if stock strayed on to roads. Today, this is deadly, both for the stock and the occupants of motor-vehicles. There is developing now quite a strong political lobby, led largely by dog-walking visitors, against fencing of our open heaths and downs. It is difficult often to persuade people who are mostly too young to appreciate the great historical changes in the usage of our countryside, that without fencing - not needed in the past - it is impossible to reintroduce the type of management of our open countryside by grazing stock that had prevailed for over 1000 years! But progress is gradually being made: it is largely a question of educating the public - who often no longer understand the old management arrangements, because they do not remember them, and don’t appreciate that, without such management, all our open uncultivated lands will become dense woodland.

Fortunately, by a series of happy accidents of history, politics and legislation, the New Forest in S.W. Hampshire remains still largely in its medieval land use of open grazing by ponies and cattle. Its vegetation, flora and fauna remains much as it was 1000 years ago - a veritable “time capsule”. Open heaths, acidic grasslands and mire communities all remain largely intact. Nothing like it - in extent - or biodiversity - now exists elsewhere in western lowland Europe. furthermore, archaeological, pedological and pollen evidence make it clear that much of this patter of diversity was established at least by Bronze Age times c.1500-2000 B.C. and thus has continuity with the remote past.

Semi-natural Woodlands The ancient woodlands of the South of England are known from documentation to have been largely managed as coppice from at least the early Middle Ages, and probably in some areas long before this time, providing a constantly renewable resource of small wood, as well as some larger timber. Since then, and above all in the last seventy years, there have been huge losses of this habitat and resource; in many parts of southern England, 80–95% of these ancient woodlands have been either totally cleared for agriculture, converted to conifer plantations or grossly changed by sheer neglect of any management. However, enough remains today, mostly in nature reserves such as the Bradfield Woods in Suffolk, to give us a picture of the continuity of this type of managed woodland from 1000 A.D.



More natural structure woodlands - pasture woodlands more a feature of parts of many of our former Royal Forests, in which, besides the King’s deer, various kinds of domestic stock were permitted to graze, if belonging to local commoners. Most of our former Royal Forests except for the New Forest, have been sadly changed; many have been totally cleared for farmlands. Others (e.g. Forest of Dean) have been converted to plantations, largely managed oak for the Navy from the late 18th century onwards, or (in the 20th Century) to conifer plantations.

The original natural woodlands would certainly have been grazed by large wild herbivores, and much evidence now available today from how plants react to the environment indicates that these woodlands would have had a wide range of tree ages, and would have been a mosaic of open, more heavily grazed areas of intermediate character. No primeval woodlands remain now in lowland western Europe, (and very little in North America either). In lowland Britain; wholly natural woodland ecosystems had certainly disappeared by 1000 A. D.

Fortunately, we still have in the New Forest, not only the heaths and grasslands mentioned above, but ancient pasture-woodlands too. These are known as the “Ancient and Ornamental Woodlands” of the forest, and cover some 8,000 acres. It is now known that at least some (probably most) of these woodlands, particularly Mark Ash Wood, have never been clear felled, though all have had larger trees selectively felled for naval timber in the 1600–1700 A. D. period. They are probably the nearest woodlands left in lowland western Europe to the primeval “wild wood” (to use Oliver Rackham’s phrase). The grazing of the original wild herbivores (such at Auroch, Red Deer, and probably Wild Horses) has been continued by the domestic stock brought in certainly well before 1,000 A. D.

The only other places in lowland Britain where relics of forest with structure probably resembling plants of the Wild Wood are in some of our medieval deer parks. These parks, many as Peter Branden showed in his thesis (London University PhD. 1963) to have been planned to incorporate such fragments as approximate to the primeval wilderness as remained in Norman times, when they were made, at least in Sussex. These woodland relics, he considered, were used to provide instant shelter for the introduced fallow deer no doubt later supplemented by planting. These old deer parks, of which few now remain in anything like their original state, included, in Sussex, such places at Eridge, East Dean and probably Parkham Park: probably also Brampton Bryar and Moccas Park in Hereford: Melbury Park in Dorset; Boconnoc Park in Cornwall; and perhaps Staverton Park in Suffolk.

Open commons, on clay or loam substrates, were once a feature of much of the medieval and later British Lowlands; this can be seen on the 1st edition 1 inch Ordinance Survey Map. Most were enclosed in the early 19th century. A few fine examples remain as Nature Reserves; perhaps the best is Ebernoe Common in West Sussex, now an N.N.R. These commons, used for grazing local commoners’ animals, were often partly wooded and so were a source of local timber and small wood. They have features of their flora and fauna in common with the medieval deer parks, particularly in their rich epiphytic



lichen floras and rich faunas of especially saproxlic invertebrates on the older trees. They are often rich in fallen or dead timber and in fungi.

All these old woodlands of semi-natural structure have some affinities with the “Wild Wood”; and they are very precious, unique places where many species have been able to survive in a spectacular manner in great contrast to the other type of ancient woodlands. The old coppice woodlands often have very rich vascular plant floras, but their management over the last 1,000 years has rendered the lichen and bryophyte floras and faunas of decaying wood, much less interesting.

Though the extensive enclosures of former common lands vastly changed much of our lowland landscapes, replacing it with either arable fields or pastures, there are far more trees and woodlands today in southern England than there were in 1000 A. D. This is because so many of the remaining commons, heath and downs have become invaded by secondary woodland, due to the combined effects of myxomatosis, and the sheer neglect of these former open areas which have become uneconomic to manage. The loss of hedges in the last 40 years or so has also changed the landscape, but this only applies to some areas. Through much of these areas such as the poor soils of the Weald in south-eastern England, the extent of secondary woodland developed c.1950 is spectacular. In much of East Anglia, the East Midlands and Lincolnshire, however, the intensive farming has had a quite different effect: woodlands have continued to shrink or disappear, and hedge loss has been very severe.

Wetlands Though our woodlands have profoundly changed in extent and character, the natural communities of the British lowlands which have suffered the greatest destruction in the last thousand years are undoubtedly the Wetlands. In Saxon and Norman times, and long after, the fenland basin of East Anglia was an untouched wilderness of vast extent, running from the north side of the city of Cambridge, right up to the S.E. of Lincoln. Besides vast areas of sedge (Cladium mariscus) fen and reed swamp, there were numerous lakes and wide winding river channels, nearly all of the Great Mere of the fenland was drained in the 17th and 18th centuries, and converted into rich farmland.

One area, however, remained untouched till 1850 - the fen basin around the lakes of Whittlesea Mere in Huntingdon. The destruction of this site by drainage from 1851 was perhaps the most tragic single loss to conservation in the last few centuries. However, we are fortunate to have quite a good record of what this site was like, in terms of species lists made by Bree (1851) and other workers before the real changes began, and then the invaluable records of an English aristocratic Lady, the Marchioness of Huntley, who was a keen amateur botanist who lived with her husband at Orlén Longuville a few miles to the north. She kept a day journal of what plants and insects she had been able to find in the area from 1844 until shortly before her death in 1893. She was able to record the plants she found in the district, particularly about the Whittlesey Mere area and its adjoining fens and bogs about Holme fen in such a way that one can interpret the catastrophic changes in the vegetation, flora



and fauna that progressively followed the drainage of the mere and the subsequent cultivation of the former wetlands around it. A valuable account of these changes can be obtained from the paper by Sheail and Wells (1980). To summarise, a magnificent complex of open lakes, reed swamps and fen with what were evidently raised bogs, developed locally over the fens, was destroyed between 1851 and the end of the 19th century. The fen areas had until after 1850 such species as: Crested Fern Dryopteris cristata Marsh Helleborine Epipactis palustris Marsh Pea Lathyrus palustris Fen Orchid Liparis loeselii Grass of Parnassus Parnassia palustris Red Rattle Pedicularis palustris Butterwort Pinguicula vulgaris Milk Parsley Peucedanum palustre Black Bog Rush Schoenus nigricans Marsh Stitchwort Stellaria palustris Marsh Fen Thelypteris palustris

The “Peat Moss” areas, shown clearly on the 1st Ed. Ordnance Survey 1” map, were clearly areas of raised bog; their flora included:- Bog Rosemary Andromeda polifolia The three Sundews Drosera anglica D. intermedia D. rotundifolia Bog Orchis Hammarbya paludosa Bog Asphodel Narthecium ossifragum Lesser Bladderwort Utricularia minor Cranberry Vaccinium oxycoccos Bog Club Moss Lycopodiella inundata

Presumably in moist, acid carr woodland these occurred:- Lemon Scented Fern Oreopteris limbosperma Ivy-leaved Bell Flower Wahlenbergia hederacea - and no doubt much else.

The bryophytes were not recorded, but the peat deposits of Holme Fen have had their sub-fossil moss remains studied in more recent years, and several species typical of untouched bogs such as Dicranum bergeri (= D. undulatum) and several species of Sphagnum (see Goodwin, 1975) for further data on this subject.

Rannoch Rush, Scheuchzeria palustris, has been found as sub-fossil remains in these Huntingdonshire former bogs. The fauna was clearly remarkable too; many characteristic birds of fens and meadow swamps such as the Bittern occurred, and there were occurrences of the Large Copper and Swallowtail. butterflies. The former is now extinct as a native of Britain.

Nearly all the species noted above, and many others, are extinct in the fenland area, and in East Anglia , except for rare occurrences in Norfolk.



Lady Huntly’s diaries record their disappearance, after many of these habitats were drained and then converted into farmlands. The only areas in Eastern England where anything of this biodiversity survives to this day are in the Norfolk Broads. These, ironically enough, are the product of human activity - medieval peat diggings - and to some degree at such sites as Dersingham Bog and Roydon Common in West Norfolk.

The Broadland Fens are now our only remaining British sites for Liparis loeselii ssp. loeselii; the next Norfolk sites named still have Pinguicula, Hammarbya, Narthecium, Vaccinium oxycoccos and the three Drosera species very locally; apart from a few remaining Norfolk wet heaths, these are the only sites left in eastern England where these plants still persist.

Two other wetland habitats need mention here, the first comprises the small calcareous spring-fens in Norfolk. Many have died out, but remarkably several survive to this day as nature reserves. However, their situation are precarious. Many are deteriorating, or have wholly lost their interest, due to water extraction (e.g. South Lopham-Redgrave Fens) or just through sheer neglect of management due to lack of the grazing or mowing formerly traditionally practised. Some however (e.g. Buxton Heath, Scarning Fen, Holt Lowes, Thelnetham Fens, Market Weston Fen, etc.) still retain much of their ancient vegetation over limited areas. These are of course now carefully managed Nature Reserves, where careful restoration of the former management regimes seems to have possibly been just in time, as long as water extraction does not become more extensive.

It is in these four places (far fewer than 30 years ago) that not only the ancient and much threatened vascular plant vegetation survives still, including many orchids and sedges, but also several bryophytes which are of definitely sub-arctic relict character. These are species which we know, from sub-fossil records in the past, have occurred in such sites since the Late Devensian (late Glacial) period, and the few survivors are clearly relics from that time. Sadly, several species which are still present in East Anglia in Victorian times have now gone. Even in the 1960s more of these bryophytes were still present in several sites in Norfolk valley fens, that now seem to be extinct. However, remarkable bryophytes of this type that still survive in Norfolk fens include such species as:- Cinclidium stygium Drepanocladus cossonii Leiocolea rutheana ssp. laxa D. lycopodiodes Philonotis calcarea Moerckia hibernica

Sadly, some seem to have gone in recent years, such as Tomentypnum (= Homalothecium) nitens Leiocolea rutheana ssp rutheana Preissia quadrata

I suspect some of them may be refound on Roydon Common, where so much excellent habitat restoration has been undertaken by the Norfolk Trust and English Nature. I fear that the rarer sub-arctic bryophytes present at Redgrave - S. Lopham Fens until mid 1960s or even 70s have gone for good.

Several of these bryophytes are very common in and characteristic of the



arctic tundra, in hollows wet in the spring. The survival of several of them, into at least recent times in lowland temperate areas such as the East Anglia valley fens, indicates that there must have been clear continuity of open, flooded wet habitats from the late Devensian until recent times. Several mosses of this type, such as:- Paludella squarrosa (found recently in an Irish fen) Helodium blandowii Tomentypnum nitens (found recently in an Irish fen) and the liverwort:- Leiocolea rutheana var. rutheanna (found recently in an Irish fen) still flourish in the rather similar valley fens on common in Jutland, Denmark, with the Marsh Saxifrage, Saxifraga hirculus, in one site only c. 50 m above sea level . These sites are grazed by horses today. the implication is that these fens must have been more or less continuously grazed by large animals -earlier, by large wild herbivores, and then, without any real break, by domestic stock - for the last 10–12,000 years. Such beasts as Aurochs and Tarpan must have soon been replaced by domestic horses and cattle.

The last types of wetlands to mention that has suffered drastic change and destruction in lowland England (and indeed everywhere in Britain and lowland western Europe) are the lowland raised bogs. Today, we have less than 2% of this habitat in Britain in a really intact state. Small areas fortunately have been conserved in nature reserves in Wales, Cumbria and the North Pennines. Larger areas of this habitat survive in parts of Wales, northern England and in Scotland, but nearly all of it has been much altered by drainage, fire or peat cutting on a large scale. Even 150 years ago, there were still large intact raised bogs in various parts of Britain, some of which could have been at least partially restored. The central plain of Ireland had huge, largely intact areas of lowland raised bogs until 40 years ago, but most of these are destroyed now by large scale mechanical peat-cutting to fuel electric power stations, except for a limited number of nature reserves. To study intact raised bog habitats, we now have to go to the tablelands of S.W. Germany in Upper Swetia, or to the mountain plateaux of the Vosges, the Ardennes, or Auvergne, where good intact examples still remain, some of which are also now carefully conserved.

However, the evidence is that raised bogs were never very common in southern England. Small examples did formerly exist in the New Forest (Cranes Moor), at Amberley in West Sussex, probably at Thursley in Surrey and around the edges of the Fenland Basin in East Anglia. All these have now been utterly changed by peat cutting and drainage.

The Sphagnum-rich valley mires of southern England have, however, fared better. Southern England is now the main centre of this interesting type of habitat. The New Forest alone, contains more fine examples of acid (and also mixed, partly alkaline) valley mires than in the rest of western Europe put together. There are also good ones, always associated with a surrounding heathland water catchment, in Surrey, Sussex, Dorset and in Norfolk. Many of these may, in their present form be the result of medieval peat cutting of former raised bogs, as their stratigraphy suggests. They are a precious biological resource almost unique now to S. England. Because of their partly



anthropogenic origin, there may indeed be more of them now than there were before 1000 A.D. in S. England, though in other parts of Britain there are certainly less good examples than there were 200 years ago, due to drainage, destruction for farmland and sheer neglect of grazing. Their formation, due at least in part to human activity, has some parallel with the Norfolk Broads fens discussed above - and increase, perhaps, in biodiversity due to changes due to man.

Conclusions and Summary By 1000 A.D., lowland England was far from being a primeval wilderness: as Rackham has made clear in his book, there was little or no primary forest left by then, and there are certainly far more trees, and secondary woodlands, now than in Saxon times. Apart from the areas of intensive agriculture, where now little even semi-natural vegetation survives (e.g. much of the Midlands and inland East Anglia) much of the South East, especially in the Weald, has a more wooded character now than 1000 years ago. Ancient hedges have been destroyed widely (except in the Weald) and nearly all of our old grasslands (mostly of anthropogenic origin) have been destroyed. Relatively few species have been totally extinguished, though many only survive now in quite limited areas.

Due fortunately to the vigorous conservation movement of the last 40 years (which has steadily increased its activities over time), at least representative fragments of most of our former natural or semi-natural plant communities (with many of their animals) survive - but most are now only left in nature reserves of one kind or another. This situation will clearly become more pronounced as time goes on, so that only in such reserves will one be able to see something of our former biodiversity, as oases in a desert of monotony.

However, even in such places, factors such as environmental pollution and hydrological changes cannot be entirely controlled. Here even the survival of limited, tiny and fragmented areas of semi-natural vegetation is often hugely precarious. It is impossible to control what happens in the terrain surrounding a small nature reserve.

Clearly the only way forward for the future, if we are to maintain the stability and biodiversity of what fragments we have left, is to try to make them much larger areas of terrain managed for conservation, so that the “core areas” are more removed from influences of change around them as far as possible.

If this can be done, there is the possibility of recreating much more extensive areas of heaths, grasslands, forests or wetlands. In some areas of England a start has been made on this exciting approach, especially by such bodies as the R.S.P.B. and the N.T. the technical know-how is already available for much of this work, but it will cost money, and will take a long time to accomplish. One very successful site that has been restored is the northern part of Martin Down in west Hampshire. Much of this was under the plough during World War II until about 1957. It was then left fallow and sheep were gradually introduced. Today most of it is once more, magnificent chalk



grassland habitat, with for example, over 1000 inflorescences of Burnt-tip Orchid (Orchis ustulata) in some years, and much else.

Such restoration will often require the re-introduction of species of plants and animals that have gone from a site; the Dutch ecologists have been very successful at such work, no doubt stimulated by the fact that they had lost so much, including virtually all their calcareous grasslands.

If we could not find the will, the time, the enthusiasm (or the money) to do this, at a time in history when the climate of opinion is more favourable to conservation polices than ever before, then the outlook would indeed be bleak; but I believe that we can succeed.

I cannot close without a note of thanks to Oliver Rackham. He has done so much by his informative and inspiring writings on our countryside and its history to stimulate us all. We owe him a large debt!

References Babington, C. C. (1860). Flora of Cambridgeshire. Bree, W. T. (1851). Recollections of a morning’s walk in the Whittlesea Fens,

Phytologist 4: 98–105. Godwin, H. (1975). The history of the British Flora (2nd ed.) Cambridge,

Cambridge University Publishers. Preston, C. D. (2000). Engulfed by suburbia or destroyed by the plough: the

ecology of extinction in Middlesex and Cambridgeshire. Watsonia 23: 59–81.

Sheail, J. & Wells, T. C. E. (1980). The Marchioness of Huntly: the written record and the herbarium. Biological journal of the Linnean Society 13: 315–330.

Watt, A. S. (1936–1940). Studies in the ecology of Breckland. Journal of Ecology 24-28.

Wells, T. C. E. & Sheail, J. (1986). Plant records for Cambridgeshire (v.c. 29) in the Marchioness of Huntly’s herbarium. Nature in Cambridgeshire 21: 38–39.

Dr. F. Rose Rotherhurst 36 St Mary’s Road Liss Hampshire GU33 7AH

CHANGES IN VEGETATION AND FLORA IN THE LAST 1,000 YEARS

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