Identification & Mapping
A hedgerow is defined as a line of trees or shrubs over 20m long and less than 5m wide, provided that at one time the trees or shrubs were more or less continuous. (from UK Steering Group on Hedgerows, published in Natural England’s Hedgerow Survey Handbook*).
A native hedgerow is defined here as one in which over 80% of the woody plants are native species.
A hedgerow tree is an isolated tree, of whatever species, age or origin, which has been deliberately or incidentally allowed to grow within a native hedgerow.
Follow DEFRA’s Hedgerow Survey Handbook (Appendix 9)* which combines measures of height, width, integrity, nutrient enrichment and other factors.
To be in ‘favourable condition’ a hedgerow must meet all the thresholds listed below:
- Undisturbed ground of at least 2m
- Herbaceous vegetation of at least 1m
- Within a 2m band of hedgerow there should be less than 20% combined cover of nettles, cleavers and docks
- Within a 2m band of hedgerow there should be a maximum of 10% non-native herbaceous species
- There should ne a maximum of 10% non-native woody species
- Height of at least 1m
- Width of at least 1.5m
- Less than 10% of the hedgerow should be made up of gaps
- No gap should be more than 5m wide
- The base of the canopy should be less than 0.5m above ground for shrubby hedgerows
* DEFRA (2007) Hedgerow Survey Handbook – A standard procedure for local surveys in the UK. Prepared on behalf of the Steering Group for the UK. DEFRA, London.