Hedgerows in the farming landscapes of Canada

Abstract

Vast areas of land are devoted to agriculture in Canada, primarily in the prairies of western Canada and in the St.Lawrence/Great Lakes Lowlands in the eastern part of the country. Farming intensified greatly in the last few decades with adverse consequences on wildlife and its habitats, in particular hedgerows. The objectives of this paper are 1) to give a historical perspective of hedgerow patterns, with emphasis on eastern Canada, 2) to describe some characteristics (origin, structure) of the different hedgerow types, 3) to depict their plant richness and composition (and other trophic levels) considered from both a conservation and agronomic perspectives, and 4) to characterise related landscape features, e.g., connectivity. Overall, hedgerows have declined on Canadian farms whereas field sizes have doubled in the last 40 years. The integrity of plant communities deteriorated due to the increasing use of agrochemicals and other management practices. At a larger scale, we show that fragmentation of the land may influence species composition in hedgerows.