ABSTRACT
Hedges and other similar field boundaries are of immense value for botanical diversity in the British countryside. Typically, they consist of a strip of trees and shrubs on a low bank, grading through marginal scrub and tall grassland into the vegetation of the enclosed field. Hawthorn and blackthorn are the most common shrubs, with ash and oak the most common trees. Botanical species richness can be an important clue to hedgerow age. Marginal grassland can sometimes include relics of formerly more species-rich communities but has frequently been degraded by herbicide and fertiliser drift in arable areas and overgrazing in pastures to leave a highly impoverished vegetation. Many rare plant species occur in British hedges, and in arable land the cultivated zone adjacent to the hedge can be of great importance for endangered arable plants. Hedges are now protected under planning law and are listed as a UK Priority Habitat (DEFRA 2012). Management for hedgerow biodiversity is supported within agri-environment schemes.
