Hedge

A hedge or hedgerow is a line of closely spaced shrubs and sometimes trees, planted and trained to form a barrier or to mark the boundary of an area, such as between neighbouring properties. Hedges used to separate a road from adjoining fields or one field from another, and of sufficient age to incorporate larger trees, are known as hedgerows. Often they serve as windbreaks to improve conditions for the adjacent crops, as in bocage country. When clipped and maintained, hedges are also a simple form of topiary.

History
The development of hedges over the centuries is preserved in their structure. The first hedges enclosed land for cereal crops during the Neolithic Age (4000–6000 years ago). The farms were of about 5 to 10 hectares (12 to 25 acres), with fields about 0.1 hectares (0.25 acres) for hand cultivation. Some hedges date from the Bronze and Iron Ages, 2000–4000 years ago, when traditional patterns of landscape became established. Others were built during the Medieval field rationalisations; more originated in the industrial boom of the 18th and 19th centuries, when heaths and uplands were enclosed.

Many hedgerows separating fields from lanes in the United Kingdom, Ireland and the Low Countries are estimated to have been in existence for more than seven hundred years, originating in the medieval period. The root word of 'hedge' is much older: it appears in the Old English language, in German (Hecke), and Dutch (haag) to mean 'enclosure', as in the name of the Dutch city The Hague, or more formally 's Gravenhage, meaning The Count's hedge. Charles the Bald is recorded as complaining in 864, at a time when most official fortifications were constructed of wooden palisades, that some unauthorized men were constructing haies et fertés – tightly interwoven hedges of hawthorns. 

In parts of Britain, early hedges were destroyed to make way for the manorial open-field system. Many were replaced after the Enclosure Acts, then removed again during modern agricultural intensification, and now some are being replanted for wildlife.

Composition 
A hedge may consist of a single species or several, typically mixed at random. In many newly planted British hedges, at least 60 per cent of the shrubs are hawthorn, blackthorn, and (in the southwest) hazel, alone or in combination. The first two are particularly effective barriers to livestock. Other shrubs and trees used include holly, beech, oak, ash, and willow; the last three can become very tall.Of the hedgerows in the Normandy region of France, Martin Blumenson said,

The hedgerow is a fence, half earth, half hedge. The wall at the base is a dirt parapet that varies in thickness from one to four or more feet and in height from three to twelve feet. Growing out of the wall is a hedge of hawthorn, brambles, vines, and trees, in thickness from one to three feet. Originally property demarcations, hedgerows protect crops and cattle from the ocean winds that sweep across the land. 

The hedgerows of Normandy became barriers that slowed the advance of Allied troops following the D-Day invasion of WWII. Allied armed forces modified their armored vehicles to facilitate breaking out of their beachheads into the Normandy bocage.

Hedgelaying
If hedges are not maintained and trimmed regularly, gaps tend to form at the base over many years. In essence, hedgelaying consists of cutting most of the way through the stem of each plant near the base, bending it over and interweaving or pleaching it between wooden stakes. This also encourages new growth from the base of each plant. Originally, the main purpose of hedgelaying was to ensure the hedge remained stock-proof. Some side branches were also removed and used as firewood.

The maintenance and laying of hedges to form an impenetrable barrier for farm animals is a skilled art. In Britain there are many local hedgelaying traditions, each with a distinct style. Hedges are still being laid todaynot only for aesthetic and functional purposes but also for their ecological role in helping wildlife and protecting against soil erosion.

Hedge trimming
An alternative to hedge laying is trimming using a tractor-mounted flail cutter or circular saw, or a hedge trimmer.The height of the cutting can be increased a little every year. Trimming a hedge helps to promote bushy growth. If a flail cutter is used, then the flail must be kept sharp to ensure that the cutting is effective on the hedge. The disadvantage of this is that the hedge species takes a number of years before it will flower again and subsequently bear fruit for wildlife and people.If the hedge is trimmed repeatedly at the same height, a 'hard knuckle' will start to form at that height – similar to the shape of a pollarded tree. Additionally, hedge trimming causes habitat destruction to species like the small eggar moth which spend nearly their entire life cycle in blackthorn and hawthorn hedgerow. This has led to a decline in the moth's population. It is now nationally scarce in Britain. 

General hedge management 
A 'hedgerow management' scale has been devised by an organisation called Hedgelink UK ranging from 1 to 10. '1' describes the action to take for a heavily over trimmed hedge, '5' is a healthy dense hedgerow more than 2 metres in height, and '10' is a hedge that has not been managed at all and has become a line of trees.

The RSPB suggest that hedges in Britain not be cut between March and August. This is to protect nesting birds, which are protected by law. 

Coppicing 
The techniques of coppicing and hard pollarding can be used to rejuvenate a hedge where hedge-laying is not appropriate. 

Types 
Instant hedge 
The term instant hedge has become known since early this century for hedging plants that are planted collectively in such a way as to form a mature hedge from the moment they are planted together, with a height of at least 1.2 metres. They are usually created from hedging elements or individual plants which means very few are actually hedges from the start, as the plants need time to grow and entwine to form a real hedge.

An example of an instant hedge can be seen at the Elveden Hall Estate in East Anglia,where fields of hedges can be seen growing in cultivated rows, since 1998. The development of this type of mature hedge has led to such products being specified by landscape architects, garden designers, property developers, insurance companies, sports clubs, schools and local councils, as well as many private home owners. Demand has also increased from planning authorities in specifying to developers that mature hedges are planted rather than just whips (a slender, unbranched shoot or plant).

Quickset hedge
A quickset hedge is a type of hedge created by planting live hazel or whitethorn (common hawthorn) cuttings directly into the earth. Once planted, these cuttings root and form new plants, creating a dense barrier. The technique is ancient, and the term quickset hedge is first recorded in 1484.The word quick in the name refers to the fact that the cuttings are living (as in "the quick and the dead"), and not to the speed at which the hedge grows, although it will establish quite rapidly. An alternative meaning of quickset hedging is any hedge formed of living plants or of living plants combined with a fence. The technique of quicksetting can also be used for many other shrubs and trees.

Devon hedge 
A Devon hedge is an earth bank topped with shrubs. The bank may be faced with turf or stone. When stone-faced, the stones are generally placed on edge, often laid flat around gateways.

A quarter of Devon's hedges are thought to be over 800 years old.There are approximately 33,000 miles (53,000 km) of Devon hedge,which is more than any other county. Traditional farming throughout the county has meant that fewer Devon hedges have been removed than elsewhere.

Devon hedges are particularly important for wildlife habitat. Around 20% of the UK's species-rich hedges occur within Devon.Over 600 species of flowering plants, 1500 species of insects, 65 species of birds and 20 species of mammals have been recorded living or feeding in Devon hedges. 

Hedge laying in Devon is usually referred to as steeping and involves cutting and laying steepers (the stems) along the top of the bank and securing them with crooks (forked sticks).

Cornish hedge
A Cornish hedge is an earth bank with stones.It normally consists of large stone blocks constructed either side of a narrow earth bank, and held in place with interlocking stones. The neat rows of square stones at the top are called "edgers". The top of the hedge is planted with grass turf. 

Sometimes hedging plants or trees are planted on the hedge to increase its windbreaking height. A rich flora develops over the lifespan of a Cornish hedge. The Cornish hedge contributes to the distinctive field-pattern of the Cornish landscape and its semi-natural wildlife habitat. There are about 30,000 miles (48,000 km) of hedges in Cornwall today. 

Hedges suffer from the effects of tree roots, burrowing rabbits, rain, wind, farm animals and people. How often repairs are needed depends on how well the hedge was built, its stone, and what has happened to it since it was last repaired. Typically a hedge needs a cycle of repair every 150 years or so, or less often if it is fenced. Building new hedges, and repairing existing hedges, is a skilled craft, and there are professional hedgers in Cornwall. The Cornish Hedge Research and Education Group (CHREG) supports the development of traditional skills and works with Cornwall Council, FWAG (Farming and Wildlife Advisory Group), Stone Academy Bodmin, Cornwall AONB, Country Trust and professional hedgers to ensure the future of Cornish Hedges in the landscape.
en.wikipedia.org

https://en.wikipedia.org/wiki/Hedge