It is estimated that some 50% of hedgrows in the UK have been removed since the early 1950s, primarily to maximise food production in the aftermath of World War II. The main hedgerow components in Wales are blackthorn (Prunus spinosa), hawthorn (Crataegus monogyna) and European gorse (Ulex europaeus), though a wide variety of other trees and shrubs also commonly contribute. Hedgerows play an important connectivity role in the UK countryside, providing links between ever-more fragmented patches of semi-natural habitat. They also provide an important early source of pollen and nectar for pollinators, important breeding and sheltering sites for birds and mammals, and an important source of autumn berries, particularly for migrating winter thrushes. For these reasons, the timing of any hedgerow management is critical. If trimming occurs in early spring or summer it will impact on the availability of spring flowers (and subsequently autumn berries, as well as disturbing breeding birds. In the not too distant past, this was considered the optimum time for hedgerow trimming. More recently, the favoured time for trimming/trashing is in late summer/early autumn, removing the vast majority of fruits before the migrating winter thrushes arrive. This modified state is illustrated and described below.