Hedgerow network landscapes: ecological functions and management principles

Bocages are one of the major landscape types found in France, Western Europe and elsewhere in the world. They were generally established in the 18th and 19th centuries, during periods of modernization of livestock farming and agriculture. The second half of the 20th century was a period of major hedge clearance. This was necessary in order to enlarge agricultural plots to the size required for mechanized farming. These clearings led to a growing awareness of the value of hedgerows beyond the property line. Soil conservation, water and landscape quality, as well as the management of crop auxiliaries to reduce the use of pesticides and pollination, have become important issues for public action. As a source of wood energy and fodder, and a carbon storage site, hedgerows help mitigate the effects of global warming and are becoming a major feature of agricultural landscapes. To take action, we need to approach the question of bocages from the multiple angles of their services, with a spatial context, that of development. The joint evolution of research, societal issues and public policy is providing frameworks for restoration and planting actions. The aim of this article is to present the ecological functions of hedgerows and bocages, which should form the basis for consideration of their development and management.