Unsprayed field margins - what are we trying to achieve?

Leave cultivated, uncropped margins or plots (includes 'lapwing plots')

A 1999 review of research into uncropped strips in northwest Europe (de Snoo & Chaney 1999) found that biodiversity was enhanced by establishing uncropped strips. Two studies found that ground-dwelling invertebrates were more abundant in uncropped strips than unsprayed cereal strips (Hawthorne & Hassall 1994, White & Hassall 1994). Another reported that ground beetles (Carabidae) were more abundant in the uncropped strip and adjacent crop than in the crop adjacent to sprayed and unsprayed crop strips (Cardwell et al. 1994). Spider (Araneae) species richness and abundance was also reported to be higher in uncropped strips than unsprayed cereal strips by one study (White & Hassall 1994). An additional study found positive results for gamebirds, songbirds and hares Lepus spp. (Anon 1990).

Additional references:

Anon (1990) Öko-Wertstreifen in Ackerbaugebieten. Jagd und Hege, 12, 5-7.

Cardwell C., Hassall M. & White P. (1994) Effects of headland management on carabid beetle communities in Breckland cereal fields. Pedobiologia, 38, 50-62.

Hawthorne A. & Hassall M. (1994) Effects of management treatments on carabid communities of cereal field margins. Pages 313-318 in: N.E. Boatman (ed.) Field Margins: Integrating agriculture and conservation. BCPC monograph No. 58.

White P. C.L. & Hassall M. (1994) Effects of management on spider communities of headlands in cereal fields. Pedobiologia, 38, 169-184.

Plant grass buffer strips/margins around arable or pasture fields

A 1999 review of research into field margins in northwest Europe (de Snoo & Chaney 1999) found that biodiversity was enhanced by establishing grass margins. Three studies found that establishing grass margins increased beneficial predatory invertebrates. Another study found no increase in invertebrate predators, but a higher abundance of field mice Apodemus spp., skylark Alauda arvensis, meadow pipit Anthus pratensis, blue-headed wagtail Motacilla flava flava and linnet Carduelis cannabina in grass margins compared to normal crop edges, particularly when the grass was tall. However, one study in the Netherlands reported that in the short-term most newly created grass margins are less species rich than existing verges.

Leave headlands in fields unsprayed (conservation headlands)

A 1999 review of research on unsprayed field margins in north-west Europe (de Snoo & Chaney 1999) found that both plants and invertebrates were enhanced in areas with unsprayed margins. Three studies reported that numbers of plant species and abundance were higher in or adjacent to unsprayed margins (e.g. Fischer & Milberg 1997, de Snoo & van der Poll 1999). One study also found that rare arable weeds returned (Schumacher 1984). Three studies reported that buffer strips of 8-23 m were necessary for caterpillars of the large white butterfly Pieris brassicae for more toxic insecticides, whereas strips of 1 m were sufficient for other insecticides (Sinha et al. 1990, Davis et al. 1991, de Jong & van der Nagel 1994). An additional study reported that a buffer strip 3 m-wide strongly decreased the effects on aquatic species next to a sprayed field (de Snoo & de Wit 1998).

Additional references:

Schumacher W. (1984) Gefährdete Ackerwildkräuter können auf ungespritzten Feldrändern erhalten warden [Endangered wild herbs can be protected/conserved on unsprayed field margins]. Mitteilungen der LÖLF, 9, 14-20.

Sinha S.N., Lakhani K.H. & Davis B.N.K. (1990) Studies of the toxicity of insecticidal drift to the first instar larvae of the Large White Butterfly Pieris brassica (Lepidoptera: Pieridae). Annals of Applied Biology, 116, 27-41.

Davis B.N.K, Lakhani K.H., Yates T.J. & Frost A.J. (1991) Bioassays on insecticide spray drift: the effects of wind speed on the mortality of Pieris brassica larvae (Lepidoptera) caused by diflubenzuron. Agriculture, Ecosystems and Environment, 36, 141-149.

de Jong F.M.W. & van der Nagel M.C. (1994) A field bioassay for side-effects of insecticides with larvae of the large white butterfly (Pieris brassica L.). Medical Faculty Landbouww. University of Gent, 59/2a, 347-355.

de Snoo G.R. & de Wit P.J. (1998) Buffer zones for reducing pesticide drift to ditches and risks to aquatic organisms. Ecotoxology and Environmental Safety, 41, 112-118.

Plant nectar flower mixture/wildflower strips

A 1999 review of research into field margins in north-west Europe (de Snoo & Chaney 1999) found that numbers of invertebrates and small mammals increased with the establishment of wildflower margins. Three studies reported that 1-1.5 m-wide flower strips resulted in higher numbers of invertebrates within the strips and field as a whole (Klinger 1987, Lys & Nentwig 1992, Nentwig 1992). One study in Switzerland found that 3 m strips were used intensively by small mammals and resulted in a population increase of common shrew Sorex araneus in spring and summer (Baumann 1996).

Additional references:

Klinger K. (1987) Auswirkungen eingesäter Randstreifen an einem Winterweizen-Feld auf Raubarthropodenfauna und den Getreideblattlausbefall. Journal of Applied Entomology, 104, 47-58.

Nentwig W. (1992) Die nühtzlingsfördernde Wirkung von Unkrautern in angesäten Unkrautstreifen. [Augmentation of beneficial arthropods by sown weed strips in agricultural areas] Z. Pflanzenkrankheiten and Pflanzenschuzt, Sonderheft, 33, 33-40.

Baumann L. (1996) The influence of field margins on populations of small mammals – a study of the population ecology of the common vole (Microtus arvalis) in sown weed strips. Field Margin Newsletter, 6/7, 26-33.