Management specifications for hedges on or bordering development sites
Please note: All views and opinions expressed in this article are purely those of the author. The content cannot necessarily be taken to represent the specific policy of any of JP Associates’ developer clients.
The importance of hedges within the landscape is now universally accepted: in 1997 the Hedgerow Regulations were drawn up to protect important hedges. JP Associates’ hedge management methods are designed to recognise the importance of hedgerows and ensure their continued status within the landscape, in particular when they form part of a development site.
The question of ownership of a hedge forming property or site boundaries often complicates its management. For the purpose of this guide we’ll assume an ideal situation where the hedge is owned or controlled by one party. In many property boundaries, ownership of the hedge will be divided between the neighbouring properties and any management will require negotiations between the different owners.
In the interests of good neighbour relations, even where one party owns the whole hedge, operations such as laying should be carried out only after consultation with the neighbouring property owners and/or tenants. In some circumstances more drastic work can be carried out in phases over a number of years. Apart from small-scale, delicate, operations, effective hedge management can only be achieved when work can be carried out to both sides of the hedge at the same time.
Hedges differ in terms of the species present, the condition of the individual trees and in the variety of woody and woodland plants present.
They are rich natural ecosystems, providing habitats for a multitude of species of flora and fauna including lower plants and many different trees, woody and woodland species. Communities of mammals, birds and invertebrates will also interact and depend on each other and the floral communities.
As with all ecosystems hedges will naturally change and develop as their environment changes through the natural processes of succession and as human influence effects change. Hedges are able to respond to environmental change as long as the rate of change does not exceed the rate at which the habitats can adapt. Thus, while the recognised practice of hedge laying will remove the majority of the leaf area and will destroy certain habitats, the operation should be timed to reduce the immediate environmental impact and is designed not to damage the base of the plant where more sensitive habitats are often found. All hedgerow management tasks should be undertaken in a way that does not exceed the hedge's ability to respond to those changes.
Maintaining the integrity of hedge banks by adding earth/material should be carried out periodically in order to prevent the erosion of the hedge bank and, therefore, a deterioration of the ecosystem. Material should be added slowly so as not to exceed the rate of change that the hedge can cope with. Traditionally, material was placed on top of the bank at the time when the hedge was layed, every five years or so. If this has not been done for some time the bank will have naturally reduced in height but the ecosystem will have responded to this change in environment. Redressing a large change in bank height in one operation will cause an environment change that the hedge cannot cope with. It will result in a drastic change to the ecosystem and an unacceptably high level of habitat loss.
Suitable growth under 100mm diameter should be layed over. The process of hedge laying is often quite a personal one and no two people will lay a hedge in exactly the same way. One of the ways in which the management of hedges on development sites differs from agricultural hedge management is that stakes or pegs should be used to hold the layed stems in place (baler twine is not a suitable alternative for development site hedges). The use of stakes or pegs will also help to create a more substantial barrier without having to use supplementary fencing.
Any accumulated debris and old fencing materials should be removed. Traditional hedge laying will usually involve removing most of the existing growth and gaps will often be exposed. Any significant gaps should be replanted with a double staggered row of suitable species (blackthorn, hawthorn, hazel, field maple, oak, and ash) using bare rooted whips (either 45–60cm or 60–90cm) planted in a double staggered row at six plants per linear metre.
Stems left to grow on as hedgerow standards should be selected from tree species rather than shrubs.
Where the Local Planning Authority (LPA) is due to adopt Public Open Spaces (POS) or other areas, the department responsible for the future management will need to be consulted on their particular requirements and policies.
On development sites the management of existing hedges will often be subject to a planning condition and the LPA will need to be consulted so that the finished hedges can be inspected and any conditions discharged.
There are various management operations for different types of hedge, classed according to the different land use circumstances.
Hedges between private residences
In all cases the exact work details will be subject to negotiation.
The primary function of hedges between private residences is as a screen and boundary so that properties enjoy both privacy and security without creating heavy overshadowing. Keeping the boundaries (and gardens) tidy is also important. In order to ensure the long-term efficiency of the hedges as screens it may be necessary to lay the hedge and allow the re-growth to form a thicker, more effective screen. Hedge laying can cause a short-term decrease in the level of screening but as the re-growth is usually more vigorous than the normal growth pattern the loss of screening should be quickly redressed.
The primary function of POS hedges is similar to that of private dwelling hedges except that the degree of screening is reduced. There remains a distinct need to maintain the integrity of the hedges to prevent further erosion of the banks and habitat loss.
Within a POS the shading provided by mature trees is probably an advantage so more stems are retained to grow on as hedgerow standards. Varying the appearance of the hedges will provide contrast to the development and add interest to the POS areas.
The primary function of site boundary hedges is to form a screen for the site, providing both security and privacy. The integrity of the screen must be ensured so that the screening effect is maximised. As with the other hedges it may well be necessary to carry out some fairly drastic operations to ensure the long-term effectiveness of the screen. As even a short-term reduction of the screen may be unacceptable to all concerned, the erection of a temporary screen fence may be needed. Site boundary management will usually only be able to proceed following agreement with the neighbouring properties or landowners and it may be necessary to phase certain more drastic operations over a number of years.