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 hedgeThis 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.

Using your results

A hedge is protected if:

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