AT THE CUTTING EDGE WITH DCV

The changing season and new quarter bring a change in the type of work we do.  Gone are the constructive tasks of summer, step building, dry stone walling, boardwalking, giving way to seemingly destructive tasks of cutting, whether in the guise of pine bashing, gorse bashing, coppicing, hedgelaying scrub bashing . . . often one of the most difficult things to explain when trying to define conservation work, or how you spend your weekends.  "But trees are good". Well yes they are but . .  . . . trees are not the only habitat!

Heathland 

Hardy's Egdon Heath  dominated the Poole basin area until the end of the 18th century - now we have lost approximately 34,000 hectares from the original 39,000 hectares. With new farming techniques agriculture claimed some of the heaths for crops, grazing, even small scale pine plantations. By 1841 about 25% of the "great" heath had disappeared. Soon the seaside town of Bournemouth began to rise from a few houses to one of the biggest resorts in the country - "eating" up heathland.  After the First World War the Forestry Commission was set up and immediately began planting pine, mainly around Wareham and Ringwood. By the 1930's more than 50% of the great heath had gone. 

The yearly loss continued at about 300 hectares a year, mostly to housing, roads and industry, in addition to aforestation. Heathland - open areas with few trees on poor, sandy soils with heather, dwarf shrubs and gorse as the main plants. In Europe these heaths only occur along the north west coastal fringes from northern Spain to Denmark. Britain still has the largest of these areas and some of the finest are here on our doorstep, in Dorset. These are mostly in the Poole basin area lying on very acid soils, very poor in nutrient which is washed down by rain beyond the reach of the plant roots.  Where clay is deposited there are often areas of wet heath and acid bog. Each of these areas have very specific plant and animal communities.

Heaths are not a stable environment soon returning to woodland being taken over by pine, gorse, birch, even rhododendron, shading out the sun loving heather resulting in loss of habitat for reptiles and insects, loss of biodiversity.  Management normally starts with removing invasive species to reclaim the heather. Some larger trees are left as perches for birds of prey and some dead trees are left for woodpeckers and insects.  On heathland we cut gorse on a rotation to maintain it as a valuable habitat for birds and insects, but once it becomes leggy it looses its usefulness.

Once cut, gorse will regrow but, unlike broadleaved trees, felled pine trees will not. Pine seedlings (possibly self sown from nearby plantations) and birch need to be pulled out and bracken needs to be controlled.  This was done by spraying but now is often done by mowing, scything or flattening. difference in age structure of the heather. However, patch burning and cutting alone are unlikely to maintain the full range of heathland species and often result in a dull monoculture of heather. A return to an extensive, mixed grazing regime is probably the best solution.  The selective grazing, browsing and trampling of cattle and ponies is effective in controlling all invasive species except rhododendron and maintains a diverse heath, keeping fertility low.  

Dry heaths support common heather, bell heather, dwarf common gorse, grasses and lichens. Bracken may grow on richer soils which often become more nutrient rich as the bracken decays.    Besides the more famous reptiles, there is a profusion of spiders, insects, ants, beetles, butterflies and moths.  The ladybird spider builds a web in a burrow to trap its prey;  the crab spider is camouflaged the same colour as the heather flowers, laying in wait to pounce on its prey. These insects provide food for birds including woodpecker, pipit, nightjar, hobby and Dartford Warbler.   The heaths are more famous for the rare sand lizard -80 - 90% of its British population in Dorset.  They need south facing sandy patches to lay eggs. The rare smooth snake (DCV logo is a coiled smooth snake) catches insects, lizards and small mammals.  

Wet heaths occur where drainage is poor.  Besides the common heather, cross leafed heather can also be seen, in addition to the rare Dorset heather, often found in these wet areas, mostly in Purbeck and only in one or two other areas in the country.    Also common are tussocks of purple moor grass, sedges, rushes and insectivorous sundews which trap insects with a sweet, sticky liquid.  The plant gradually digests the insect to top up its nutrients The silver studded blue butterfly can often be spotted on damp heath, as can the bog bush cricket.  The more rare large marsh grasshopper lives in the wettest bogs, calling with a ticking sound in late summer. Some bogs and pools can have up to 20 different dragonflies breeding in them.  Wetland bogs and fens become drier as willow and birch invade and suck out the moisture

Coppice

 Coppicing - cutting back trees or shrubs to allow regrowth, providing a fresh crop of wood which can be cut once more, renewing the cycle  providing a renewable, self-sustaining resource. A coppiced woodland, traditionally hazel with oak standards, for centuries provided for many of the needs of man - nothing would be wasted, even the smallest twigs bundled into faggots to be burnt.  Traditionally all of the cut material would have been taken away to be used in some form or another, leaving the floor of the wood "clean" and incidentally maintaining the correct nutrient level for the native flora. To the conservationist today, it is the wildlife "spin off", the rich flora and fauna, that is the main reason for maintaining an uneconomic and labour management process today. Coppicing gives a wood an immense variety of structure, encouraging species once restricted to rides or the wood edge.  All stages in growth are present from the newly felled area to the closed canopy of young trees. The flood of light in a recently coppiced area promotes a flush of woodland flowers, bluebell, wood anemone, primrose etc, important for a great many insects.  As the shrubs grow, other species move in;  nightingales prefer 4 to 9 year old regrowth and a high density of essentially scrub-breeding birds such as whitethroat, blackcap and garden warbler can be maintained. Major threats to our coppiced woodlands are forestry, farming and sheer neglect, though a coppice wood can be restored even after 100 years without having been touched.  The most widespread hedge shrubs, hawthorn, blackthorn and elder, are essentially scrub plants adapted to colonise open land.  Other species cannot easily seed into open land and so colonise hedges slowly if at all. When these species are found in a hedge it probably indicated a woodland origin, eg hazel, spindle, field maple.  At ground level perennial herbs flourish, cow parsley, hedge parsley.  Plants indicating woodland origin include dog's mercury, bluebell, primrose, wood anemone, wood spurge.  Birds, small mammals, reptiles, amphibians and invertebrates use the hedgerow for haven, home or food - over 100 types of moth feed on hawthorn alone and nearly as many utilise blackthorn.

Chalk downland

Flower rich, nutrient poor with thin soils, during the 18th and 19th centuries chalk downlands were extensively grazed by sheep.  Today areas of unploughed downland have become smaller, increasingly isolated and more confined to steep slopes difficult to plough. The demise of the rabbit put paid to many sites not being grazed by sheep, with nothing to arrest the invasion of scrub (small trees and shrubs that occur as a phase in the development of woodland from open habitat) comprising hawthorn, blackthorn and ash.  This results in grass being shaded out and soil being enriched. The unique flora and fauna that have taken thousands of years to adapt and establish could be lost. Neglect of these sites for as little as ten years can see the loss of a wonderful and diverse habitat -  to reverse it with the diversity of plant and animal life may take three times as long.  This is why we cut selected areas of scrub whilst carefully maintaining a good age structure to ensure habitats for creatures of different species. Old grazed chalk downland is remarkable for the highly intricate mixture of plant species - a careful search may reveal as many as 40 species per square metre.  The first flowers to dominate a downland hillside are usually yellow - cowslip, bulbous buttercup, bird's foot trefoil and horseshoe vetch.  Blues, pinks and whites then follow in profusion with milkworts, squinancywort, dropwort, thyme, oxeye daisy and rampion. Late summer and autumn, the purples and mauves of scabious, devil's bit scabious, knapweed and felwort.  Many different species of orchid display their elegance from May through to the end of September when the white flowers of autumn lady's tresses add points of interest among the dry flower heads. Butterflies thrive too, often large populations of many species, together with many hundreds of other insects

Hedgerows 

From a wildlife point of view hedges are invaluable, providing safe havens, "corridors" between ecosystems for Britain's flora and fauna, mainly of woodland origin.   They provide strong, stock-proof barriers, shelter, food for free and help prevent soil erosion Management of hedges is labour intensive.  It requires time to clear out a hedge - of dead wood, brambles, unsuitable stems (pleachers), to carefully cut through remaining pleachers - just far enough -  bend them over (always uphill), trim the excess and stake the hedge to keep it secure. A hedge neglected or constantly flailed, will become gappy at the base and soon deteriorate into the remnant hedges all too frequently seen in our countryside today. Laying, together with selective mechanical trimming, rejuvenates the hedge, ensuring a long and healthy life, creates a strong barrier and diversity of wildlife. Laid stems will survive as long as the necessary nutrient flow can still take place from roots to tip.  Bark, bast, cambium and at least a little sapwood must be left, joined in a thin strip of stem from which the upper portions can draw nourishment.   Ideally the hedge would be left to grow on a little after the last trimming before laying.  

There were once twenty five or more distinct styles of hedging in Britain, developed down the centuries according to what was to be kept in - or out - of the field, and dictated by need, by the land itself and what trees best suited it and by the craftsmen who passed the skills down the generations. The Midlands hedge - primarily a bullock fence: cut pleachers angled at about 30 degrees to produce a hedge 4' - 4-6"high, the brushy tops left pointing into the field, keeping cattle away from tasty new shoots.   Welsh hedges, designed primarily as sheep fences, thus they need to be dense but not necessarily very high, depending on the local breed of sheep. 

In Dorset we lay our hedges in the "flying" hedge style. This name covers all low hedges with pleachers laid flat or nearly flat along a medium to high double sided bank. Other common features are the use of crooks rather than stakes and the absence of binding along the top. The decline in farm labourers, mechanisation, changing farm patterns and increased urban development have all played a part in the demise of the hedgerow.  An estimated 1000 miles a year during 1925-1939, 20,000 miles lost between 1945—1970 to various non agricultural sources, 120,000 miles grubbed up by farmers. Chalk downland and heathland are rich in species that have adapted to the nutrient poor soils. All of the cut wood needs to be burnt or removed from these sites because if left to rot down it enriches the soil too much and different plants can invade upsetting the delicate balance This is why we have big bonfires when we are scrub and pine bashing. - the site for the fire being carefully selected to minimise damage.

Yes . . .  Trees are wonderful but spare a thought for all the other unique and varied habitats on our doorstep