Naturenet: How to survey a hedge according to the 1997 Regulations

How to survey a hedge according to the 1997 Regulations
By Alina Congreve

First find your Hedge
Laid hedge This brief guide should help people with little or no experience of using the Hedgerow Regulations 1997 to survey hedgerows. Some experience of field botany, especially common trees and shrubs would be a help. You may also find it easier if you are a beginner to survey outside the winter months. The Regulations provide legal protection for only those hedgerows that meet their criteria. Start off by walking along the whole length of the hedge, checking there are no large gaps. If there are gaps larger than 20m then you will need to survey it as two or more separate hedges. No real guidance is given about what constitutes a hedge and you will have to make your own judgments. When does a hedge become so gappy it is reduced to a line of trees? In the case of my own survey work, a level of 35% gaps was chosen. Hedge volume is also important. When does a hedge become so short it is not a hedge? In this study a cut off point of less than 1m tall was chosen.

Second find which section to measure
Secondly calculate the length of the hedge. With shorter hedges this is best done with a tape measure. With longer hedges it can be calculated with an OS map. If the hedge is 30m or less in length then survey the whole hedge. If the hedge is between 30-100m then survey the central 30m. If the hedge is between 100-200m long then divide it in two and survey the central 30m of the two sections. If the hedge is over 200m divide it in to three sections and survey the central 30m of each of the thirds. The width of each of these quadrats is the width of the hedge. It is usually possible to survey a hedge from one side except in the cases of the highest and thickest hedges.

Thirdly survey the woody species
Once you have found the correct sections to survey you then need to identify the woody species present. The most important criteria determining whether a hedge will meet the Regulations is the number of woody species. These are listed on Schedule 3 of the Hedgerow Regulations. Some of the species listed, such as wild cotoneaster and downy current are very rare and you are unlikely to ever encounter these in the field. Only those species listed on the Schedule count. Currently trees like sycamore will not add to the score. Neither will garden plantings lilac or fuchsia. Recent planting is also disqualified, those that are less than 30 years old. This can often be difficult to determine in the field.

Fourthly survey the herb layer
The Regulations do not give any guidance on how to survey the herb layer. In this case the quadrat used was the same size as for the woody vegetation. It would also be possible to use a smaller quadrat of 10m long times the width of the hedge. Values on this table are given in percentages. Sometime these are less than 100% in total due to heavy grazing pressure. Recording all species and abundance is not necessary for the Regulations but it is an important component of other survey methods.

All the other features require you to survey the whole hedge.

Standard trees – there is no mention that a standard tree must also be a woody species so in this case you could count a sycamore or domestic apple for example. To qualify as a standard tree for a single stemmed tree the whole stem has to have a diameter of 20cm or more at 1.3m from the ground. For multi-stemmed trees it must have at least two stems over 15cm diameter at 1.3m from the ground.
Record if there are any rare trees in the whole length of the hedge. According to the Regulations a rare tree is a black poplar, large-leafed lime, small-leafed lime, and wild service tree.
A hedge gains extra points if it connects to another hedge. Count all the other hedges that join the one you are surveying. A connection is when the feature actually touches the hedge you are surveying or would touch if the hedge continued in a straight line for up to 10m. The same ‘10m in a straight line’ also applies to pond and wood connections discussed later.
Does the hedge run parallel to a footpath, bridleway or BOAT (but not necessarily a normal adopted vehicular highway unless it also is one of these)
Is there a hedge that runs parallel within 15m? This does not apply to hedges that are parallel to footpaths, bridleways or byways open to all traffic.
Does the hedge connect to one or more woodlands composed of 50% or more broad leafed trees? You will also need to make your own judgments about the additional features listed in the Regulations such as ponds and woods. When does a wood qualify as a wood and when is it only a group of trees? No guidance is given on this matter in the Regulations. When the Department of the Environment carried out a study about the Regulations they used the guidelines in the Phase 1 Handbook but there is no legal reason why you need to.
Does the hedge connect to any ponds? When does a pond qualify as a pond. This is a particular problem in chalk areas where a pond may not have water in all year round.
Record the percentage of gaps in the hedgerow. It is not clear whether gaps filled with species not occurring on the woody species list for example bramble or sycamore count as gaps.
Record if the hedge has a wall or bank along half or more of its length.
Record if the hedge has a ditch along half or more of its length. This can include ancient features as well as those of more recent agricultural origin.
Record if the hedge has three of more woodland species. These are herb layer plants that are listed on Schedule two of the Regulations such as dog’s mercury and bluebells. There are also a number of grasses found it woodland areas that make surveying difficult for less confident botanist and during the winter months such as such as wood millet and wood meadow grass. If you are new to surveying try and record those you can easily identify like bluebells. It is not worth spending a lot of time on this section as it only makes hedges qualify that would not otherwise in a tiny minority of cases.

Using your results

A hedge is protected if:

Paragraph Four

A wall or bank along half or more of the length
A ditch along half or more of the length
An average of one standard tree or more per 50m of hedgerow
Gaps which do not add up to more than 10% of the hedge
Three woodland species
A parallel hedge within 15m
Connections scoring four points. Connections to a hedge scores one point. Connections to a pond or wood score two points

It has an average of seven or more woody species in the surveyed section/s.

It has an average of six woody species in the surveyed section/s and three ore more features in paragraph four of the Regulations.
It has six woody species and one of the following rare trees – Black Poplar, Large leafed lime, small leafed lime, wild service tree.
It has and average of five wood species on average in the surveyed section(s) and has four ore more features listed in paragraph four.
It has four woody species on average in the surveyed section(s); is adjacent to a footpath, bridleway or BOAT (but not necessarily a normal adopted vehicular highway unless it also is one of these) and has two or more features listed in paragraph four.

Where a hedgerow is situated wholly or partly in the county (as constituted on the first of April 1997) of the City of Kingston Upon Hull, Cumbria, Darlington, Durham, East Riding of Yorkshire, Hartlepool, Lancashire, Middlesbrough, North East Lincolnshire, Northumberland, North Yorkshire, Redcar and Cleveland, Stockton-on-Tees, Tyne and Wear, West Yorkshire or York the number of woody species mention is to be treated as reduced by one.

References

CPRE (1999) Hedging your Bets. 19pp (Council for the Protection of Rural England, London).
Cummins. R French, D Bunce, B Howard, D Barr, C (1992) Diversity in British Hedgerows. (Institute of Terrestrial Ecology, Huntingdon).
DETR (1999) Research into proposed criteria defining ‘important’ hedgerows. (London, Department of the Environment Transport and the Regions).
JNCC (1993) Handbook for Phase 1 Habitat Survey: A technique for environmental audit. (Peterborough, Joint Nature Conservation Committee).
Pollard, E. Hooper M. D, Moore NW (1974) Hedges: New Naturalist Series 58. (London, Harper Collins).

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