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WHERE HAVE ALL THE WILDFLOWERS GONE? PETER MARREN I think few would disagree that there are fewer wild flowers around in the countryside than there used to be only thirty or forty years ago. The statistics tell their own story – 90% of natural ‘neutral’ grassland gone and so forth. Whilst the diversity of species has actually increased over this period, with many more alien plants being recorded than ever before, the density of most native wild flowers has fallen. Although few species have become nationally extinct, extinctions at a local level seem to be much higher, especially in lowland, intensively farmed counties. This is the subject of my talk today. It has what I hope will be an unexpected ending. I don’t know if Martin has mentioned, but I live in a swamp – no I really do! – in a fairly rural part of Wiltshire, in the upper part of the Kennet Valley. I can look out of the window on what looks like a very attractive landscape. There are the water meadows of the River Kennet – lovely flat, alluvial grassland which has never been built on because the houses would just flood. On the slopes above there is what used to be chalk downland, but now mostly re-sown grassland and cereal crops, and on the top of the hill there is claywith-flints supporting mixed woodland with a broad apron of chalk shrubs. All of this forms a landscape which was essentially semi-natural in character, but has also been used for rearing sheep. The lambs were fattened up on the water meadows, which were given a winter dose of natural fertiliser by the ‘village drowner,’ who operated the sluice gates. The water in the fine network of channels would be drained off in the Spring so that the grass could grow fast enough for the lambing season. Later on, when the season got going on the downs, the sheep would move up there, and the local hazel wood provided convenient fencing for the sheep at night. So it was an inter-related landscape. All this came crashing down in ruins in about 1939 when the chalk downs were largely ploughed; now they are ‘set-aside’ and have lost most of their characteristic flowers. The woods on the top have been preserved, but underplanted with a lot of conifers grown to encourage pheasants. Most of the older trees were felled during the war, when Ramsbury was an American Dakota base, and the woods have grown shady. The only places you find a lot of flowers are around the edge. The water meadows down below are gradually filling up with Stinging Nettles. Over the last seven years I have seen them force their way through the grasslands and along the riverbanks, smothering the moschatels and other plants of alluvial soils. Not far away, upstream of me lives Jack Oliver, who has been studying the spread of Stinging Nettles; comparing today’s flora with that so faithfully and finely recorded by Donald Grose in the 1950s, gives some basis for the spread of the nettle. Briefly, it has changed from being the seventh commonest plant in Wiltshire to being the commonest. Its density has also increased, and the nettle is now present in every kilometre square, and in habitats where it was not present before. Not only this, it has also grown in size. They are taller than ever, with the record going to some woodland nettles on rich soil at over twenty feet long! Contrariwise, I have noticed a corresponding fall in one of the county’s most
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characteristic flowers, the Meadow Cranesbill. When I first came here, in 1993, there was still quite a lot of ‘the Wiltshire weed’ in Ramsbury – one particular field bank was quite blue with it. There is still plenty of it about, but it is no longer a spectacle in the way it used to be. In its place you tend to find either Stinging Nettles or Cow Parsley. People like Cow Parsley – it looks nice and fluffy for about three days in the year, but given enough nitrogen, it just goes mad, and the Meadow Cranesbill can only get a look in on the poorer, drier soils up on the downs. In places, it’s beginning to look as though someone has pulled a plug out somewhere, and all the colour is draining from the landscape leaving us only the green plants. This might be just the view from my window, or it might be representative of an emerging pattern. I have been trying to measure the rate at which species have been disappearing from other counties. The two papers that I am aware of were for Northamptonshire by Duncan McCollin and Linda Moore, and for Cambridgeshire and Middlesex by another of today’s speakers, Chris Preston. What they did was to look at the recent County Floras and note which flowers had become locally extinct during the period in which records have been available – in the case of Cambridgeshire there are records reaching right back to the 17th Century. The results were rather startling. For Northamptonshire, out of a Flora of about 900 species, 100 are now believed extinct, another 154 are categorised as rare i.e. they are only found at between 3 and 15 sites, and another 108 seem to be teetering on the brink of extinction, found at 3 sites or less. When Druce produced his Flora of Northamptonshire in 1930, some of these species were still quite common. Now 360 species out of 900 are rare or gone. The most recent Flora was written in 1995, so it is possible to subtract the date of Druce’s Flora from this and to calculate the rate of decline of these species as about 1·4 species a year. But this is an averaged figure for the last 60 years, and it is probable that the actual rate in recent decades has been even higher – maybe two or three species a year. People writing County Floras are naturally reluctant to write off a plant as extinct, and look on it rather as a plant to refind. But if a flower has not been seen for 10 years it has probably gone for good. So the extinction rate may be even higher than these Floras indicate. Chris Preston will probably want to talk more about the situation in Cambridgeshire and Middlesex. However, it is interesting that although the extinction rate was somewhat lower than in Northamptonshire, it was almost equally high in both counties, about 0·8 and 0·7 species per year respectively. But the extinction patterns were different. Cambridgeshire is of course an agricultural county with a relatively low density of urbanisation. If you don’t count Peterborough – not many people do! – there is only one big town, Cambridge. Whereas Middlesex is pretty well all built up. Yet the difference in extinction rate between these two counties is not all that great. However, the pattern is different. Cambridgeshire lost a lot of plants in the 19th Century because intensive agriculture pretty well started in the fens. The County had lost many of its special plants of fenland and downland even by 1860, when Babington produced his great Cambridge Flora – incidentally the first Flora to have as a major theme the idea of loss of species due to the demands on the
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land. In Middlesex, the rate of decline has been much more constant, presumably because the urbanisation of the county has proceeded fairly steadily; whilst Cambridgeshire’s rate of decline seems to fluctuate with the demands of intensive agriculture. The last Flora there was produced in 1964, at the height of the farming boom, and maybe a new one would give a more reassuring picture. However, the results all seem to indicate a loss rate of about one species per year. From year to year it’s insignificant, but over a century it could mean losing more than 10% of a county’s native flora. Of course among that 10% will be many species of the greatest interest to conservationists. I thought that I would try looking at as many County Floras as I could get my hands on and try to see whether the rate of extinction in other counties was comparable to these three. Although it was not always possible to be as accurate, it did seem that the mean of one native species per county per year held good over much of England, Wales and even parts of Scotland. The trouble with County Floras is that to do this properly you ideally need one dated about 1900 to compare with another that is bang up-to-date, and both of them recording broadly along the same kind of system. One of the most elegaic of modern Floras is Francis Simpson’s Flora of Suffolk – no doubt the next Francis Simpson (County Recorder and author of the Flora) will come from your ranks. He records the passage of one of England’s most flowerfilled counties to a place where the flora has been marginalised – in places almost banished. But Suffolk is bigger than Cambridgeshire, and has more wild places. Its extinction rate is lower, though it follows broadly the same pattern as Cambridgeshire, with the obvious message that modern farming is bad for flowers. Working backwards, a big post-war extinction boom, relatively few extinctions between 1890–1939 (when there was a lot of permanent pasture), and then before that (where records permit) another extinction boom during the time before the repeal of the Corn Laws and the drainage of the Fens. The pastoral counties of the west, like Gloucestershire for example, seem to have a different pattern again with relatively few extinctions up to the 1950s, and then a whole burst, possibly as a result of agricultural intensification, and also from the coniferisation of native woods. These things are fairly easily calculated once you have got the raw figures. You need to know how many native plants there are in a county, of course, and that’s easier said than done because the definition of a native plant is subjective in itself. A nationally native plant may not necessarily be native in that County. Some authors do not even bother to distinguish between native and established plants, perhaps dismissing it as an impossibility. But given a rough idea of how many native species there are, you can calculate the percentage of extinct species from the total Flora. If you know the approximate date of extinction for each plant you can analyse the pattern of extinction decade by decade. Of course counties don’t just lose plants, they also gain plants. In the case of Northamptonshire the gain outweighs the loss so long as you make no distinction about what is native and what isn’t. Floras of the 1990s generally have more species in them than Floras of the 1930s. This is for two reasons:
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the recording effort now is much greater than it was then. For example, the modern Flora of Hampshire (1995) has hundreds more species in it than the Townsend Flora of 1889. Not that many species have come in since then, they had simply been over-looked. The other reason is that non-native species are recorded much more now than in the past and many of them are more naturalised in the landscape than they were. Some are of course invasive and have taken over on riverbanks and waterways. So it isn’t just a question of numbers. The losses are found amongst plants which belong to Britain, that have been here for thousands of years, and are often characteristic of particular wild habitats. The gains tend to be more or less ubiquitous flowers, plants that are at home in gardens, old walls, quarries and other disturbed sites. When you examine the types of flowers that tend to become extinct, there does seem to be an awful lot in common between the counties of Britain. Some groups seem to be doing particularly badly, such as insectivorous plants. Practically every one of the sundews, bladderworts and butterworts in Britain are declining. The New Atlas of the British and Irish Flora will show you that for some of them there are as many or more past records than present ones. For example, the Oblong-leaved Sundew Drosera intermedia, was present in 254 grid squares, but between 1970 and now it has disappeared from 44, and before that it had disappeared from 210 – so its natural range has contracted by more than half. It is contracting to its heartlands, for example to the Atlantic blanket bogs of north-west Scotland and the Hebrides, to the heartland of the New Forest and the boggy heaths of Aldershot, and to a lesser extent in corners of Cumbria, West Wales, Cornwall and Devon. It means you are much less likely to be living near a sundew than your grandfather was. If you lived in the middle of London, you could go to see a Sundew at Wimbledon Common, possibly Hampstead Heath and certainly Epping Forest. Now you would have to go to somewhere like Guildford or Aldershot, that is, a train ride away rather than a bus ride away. And that’s tough luck, because sundews are wonderful things – Darwin thought that they were one of the greatest wonders of the plant world. There’s nothing like a sinister plant that moves and eats insects to stimulate a child to take an interest in wildflowers. Well, we’ve wiped them out of most of the lowlands. The reason why these particular plants are declining is partly due to their insectivorous nature. In order to make their sticky traps they need to direct much of the energy that other plants would use for growth and leaf production into trap production. This means that they have pathetic root systems and their photosynthetic capacity is far less than that of other plants of their size, so they are not that fitted to survive in a competitive world. Because they get nitrogen and other nutrients from the insects rather than the soil, these plants concentrate on peat bogs where nothing else can grow. However, most English peat is in our gardens. Our largest peat bog, Thorne and Hatfield Moors have no sundews, and no butterworts or bladderworts either. The Government Countryside Survey monitoring has shown there is a big problem with nitrogen pollution in Britain. It’s encouraging the spread of invasive scrub plants, and tall grasses like Purple Moor Grass and Tor-grass. It is increasing the competition and the pressure on tiny little insectivorous
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plants. Taller plants shade them out and create a cooler micro-climate so that they cannot catch insects. Arable weeds are another threatened group because of the use of heavy fertiliser loads, herbicides and the kind of high density cereals that don’t leave any room for weeds. Yet another is submerged aquatic plants – like pondweeds, which are suffering from an overall loss of water quality. Our River Kennet has become noticeably yellower in recent years, with its former champagne sparkle restricted to inflow channels. In Ramsbury, the Stream Water Crowfoot Ranunculus pencillatus, has declined, dragging down with it a whole freshwater ecosystem. The root systems are not developing because the rivers are full of silt, and they are also not getting enough sunshine because the water is filthy and full of dead plankton. But this pales in comparison to the decline of the submerged aquatics recorded by the Northamptonshire Flora. Even species like the Greater Duckweed, that was abundant in the 1930s, are down to about two sites in Northamptonshire. Never mind the Botany, what is that saying about the quality of water in Northamptonshire? Another declining group is the fern family – pillworts, clubmosses and some ferns are becoming upland plants, in retreat across much of England. Although woodlands do not seem to be suffering to the same extent as other habitats from eutrophication of the soil, we all know that coppiced woodlands are not as colourful as they used to be. It seems that every where you go coloured plants are being overtaken by green ones – What is to blame? Is it abandonment of coppicing, or because the flowers are eaten by deer – or is there something more sinister at work? – Like nitrogen overload, replacing Violets, Speedwells and Primroses with lawns of Dog’s Mercury? Each individual species disappearing represents the thin end of the wedge. For every one that has gone, you have a lot of other less common species in decline. Understandably most conservation effort has gone into the rarest flowers in Britain. But these are in nothing like as much danger as the next group up, the scarce plants, the ‘Pink Data Book’ if you like. They are more widespread in the landscape, and therefore open to factors affecting the whole landscape, like agriculture, urbanisation etc. – more so than rare plants confined to small, often marginal and well protected areas. What we really need is a Data Book of Common Plants that grades frequency rather than simply indicating presence or absence. It is the common plants that are the fabric of our landscape, and mean the most to us. When the last Meadow Cranesbill disappears from my view I am going to be more affected than by the disappearance of a rare orchid in Caithness. It is at the personal and emotional level that these declines affect us. I don’t want to end on too gloomy a note. It is human to be optimistic. Winnie-the-Pooh has a more attractive philosophy than Eeyore, even if it is, mostly, rubbish. If we just want a flora as it was in 1600 then it is indeed under attack. If however we embrace change as Tony Blair entreats us to, we can be much more optimistic. I think it was Martin Ingruoiue who reminded us that in evolutionary terms this is the most exciting time since the late Ice Age. Plants from all over the world (including 100 cotoneasters) are coming together in
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Britain for the first time, meeting one another on ghostly railway sidings and urban wastelands, and sometimes exchanging genes. Evolution is going on at an accelerated rate in the streets, on the road verges, quarries and derelict land. Some people would argue that the woods around London are being improved by the addition of plants from suburban gardens, We can see the future, and it’s cosmopolitan. It is a question of perception. Many new and exciting things are going on in British botany. We are losing traditional species and gaining new ones. This process strikes me as irreversible. Personally, I’d be happy with the flora of 1600 – apart from anything else it was easier to identify. But the flora of the future will mirror our own lives, not the landscape of the past, however much revered. As a conservation message, it’s gloomy. But as a botanical one, it is a source for wonder and inspiration for as long as people care about wild plants. Peter Marren, Ramsbury Wiltshire
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