Название | British Wild Flowers: A photographic guide to every common species |
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Автор произведения | Paul Sterry |
Жанр | Природа и животные |
Серия | |
Издательство | Природа и животные |
Год выпуска | 0 |
isbn | 9780008144586 |
PALMATE
LOBED MARGIN
CLASPING BASE
TRIFOLIATE (OR TREFOIL)
FINELY DIVIDED
WHEREVER CONDITIONS ARE SUITABLE for life then plants are likely to grow. Although some species are rather catholic with regard to where they grow, most are much more specific, influenced by factors such as underlying soil type, whether the soil is waterlogged or free-draining, summer and winter temperature extremes and so on. Consequently, where environmental conditions are broadly similar, the same plant species are likely to be found; where these communities are recognisably distinct they are referred to by specific habitat names. In Britain, many of our most distinct habitats owe their existence to past and present human activity, so they are classed as semi-natural in ecological terms.
DECIDUOUS WOODLAND
Woodlands of deciduous trees are found throughout most of the region. They are (or would be, if allowed to flourish) the dominant natural forest type of all regions except in parts of Scotland where evergreen conifers predominate. As their name suggests, deciduous trees have shed their leaves by winter and grow a new set the following spring. The seasonality seen in deciduous woodland is among the most marked and easily observed of any habitat in the region.
Almost all woodland in the region has been, and still is, influenced in some way by man. This might take the form of simple disturbance by walkers, at one end of the spectrum, or clear-felling at the other. Man’s influence is not always to the detriment of wildlife, however. Sympathetic coppicing of Hazel and Ash, for example, can encourage a profusion of wild flowers. In particularly rich locations, carpets of Bluebells, Wood Anemones and Wood Sorrel form the backdrop for more unusual species such as Early Purple Orchid and Greater Butterfly Orchid, Goldilocks Buttercup and Herb-Paris.
Centuries of woodland coppicing have inadvertently created the perfect environment for Bluebells to thrive. A carpet of these lovely plants is a quintessentially English scene.
CONIFEROUS WOODLAND
Areas of native conifer woodland are restricted to a few relict pockets of Caledonian pine forest in the Highlands of Scotland. Conifers that are seen almost everywhere else in Britain and Ireland have either been planted or have seeded themselves from mature plantations. Our native conifer forests harbour an intriguing selection of plants, such as various wintergreen species, Twinflower and Creeping Lady’s-tresses, but conifer plantations are usually species-poor.
HEDGEROWS AND SCRUB
Once so much a feature of the British countryside, hedgerows have suffered a dramatic decline in recent decades. Many hedgerows have either been grubbed out by farmers keen to expand arable field sizes or, more insidiously, wrecked – both in terms of appearance and in their value to wildlife – by inappropriate cutting regimes.
The extent of scrub in the landscape has also diminished in recent times. Although scrub is difficult to define in strict habitat terms, most people would understand the word to mean a loose assemblage of tangled, medium-sized shrubs and bushes interspersed with patches of spreading plants such as Bramble and areas of grassland. Scrub is frequently despised by landowners – sometimes even by naturalists too – but its value to many species formerly considered so common and widespread as not to merit conservation attention should not be underestimated.
Hedgerows usually comprise the species, and acquire the character, of any woodland edge in the vicinity. Scrub, too, reflects the botanical composition of the surrounding area. However, because scrub is essentially a colonising habitat, and not an established one, the bushes and shrubs that comprise tend to be those that grow the fastest.
GRASSLAND AND FARMLAND
Full of wild flowers and native grass species, a good grassy meadow is a delight to anyone with an eye for colour and an interest in natural history. Unfortunately, prime sites are comparatively few and far between these days, either lost to the plough or ‘improved’ by farmers for grazing, by seeding with fast-growing, non-native grass species and by applying selective herbicides. When this happens, the grassland loses its intrinsic botanical interest and value.
It should not be forgotten that, in Britain and Ireland, grassland is a man-made habitat, the result of woodland clearance for grazing in centuries past. If a site is to be maintained as grassland, continued grazing or cutting is needed to ensure that scrub does not regenerate. In the past, the way in which grassland was managed had the beneficial side-effect – from a naturalists’ perspective – of increasing botanical diversity. Under modern ‘efficient’ farming regimes the reverse is the case.
Although arable fields may fall loosely into the category of grasslands (crop species such as wheat, barley and oats are grasses after all), their botanical interest tends to be minimal in many areas. Modern herbicides ensure that ‘weeds’ are kept to a minimum, and decades of chemical use have resulted in the soil’s seed bank being depleted dramatically. Many of the more delicate arable ‘weed’ species are essentially things of the past, often relegated to a few scraps of marginal land that escape spraying either by luck or, in a few instances, through the foresight of farmers. Arable weeds depend on disturbance, being unable to compete in stable grassland communities. So there is a sad irony to the fact that grant-funded ‘conservation’ schemes that create wildlife ‘headlands’ are often the final nail in the coffin for these scarce species, which become crowded out by the vigorous growth of seeded rank grasses and clovers.
HEATHLAND
Heathlands are essentially restricted to southern England, with the majority of sites concentrated in Surrey, Hampshire and Dorset. However, further isolated examples of heath-land can be found further afield, in south Devon and Suffolk, for example, and in coastal districts of Cornwall and Pembrokeshire. This fragmented distribution adds to the problems that beset the habitat: ‘island’ populations of plants and animals have little chance of receiving genetic input from other sites.
Heathland owes its existence to man, and came about following forest clearance on acid, sandy soils. Regimes of grazing, cutting and periodic burning in the past have helped maintain heathland, and continued management is needed to ensure an appropriate balance between scrub encroachment and the maintenance of an open habitat. Ironically, man is also the biggest threat to the habitat: uncontrolled burns cause