The importance of hedgerow field boundaries to densities of beneficial invertebrates in cereals.

Abstract

The field boundary can directly influence the invertebrates not only found within the uncropped edge but also within the adjacent arable field. A number of the invertebrates families found in the crop are important components in the nestling diet of farmland bird species, and many of these birds have declined significantly in the last few decades partly due to a reduction in the food available for their young within the arable habitat. Densities of these beneficial invertebrate groups can vary greatly between sites but a major factor influencing abundance is the type of field boundary. A field headland with a hedge boundary can contain higher densities of some of these groups such as Heteroptera, compared to a similar field adjacent to a non-woody edge such as grass-edges/wire fences. The influence of hedge aspect in relation to abundance of these beneficial food groups and distribution within the field compared to the boundary is also discussed.