Cover crops and related methods for enhancing agricultural biodiversity and conservation biocontrol: successful case studies

  • Published source details Tillman P.G., Smith H.A. & Holland J.M. (2012) Cover crops and related methods for enhancing agricultural biodiversity and conservation biocontrol: successful case studies. Pages 309-327 in: G.M. Gurr, S.D. Wratten & W.E. Snyder (eds.) Biodiversity and Insect Pests: Key Issues for Sustainable Management. Wiley-Blackwell, Oxford, UK.


This study is summarised as evidence for the following.

Action Category

Create beetle banks

Action Link
Natural Pest Control
  1. Create beetle banks

    A review (Tillman et al. 2012) described one study (Collins et al. 2002, summarised above) which found that natural predators reduced aphid (Aphidoidea) numbers up to 58 m from a beetle bank, but with greatest reductions at 8 m from the bank. Another study (Thomas 1990) found reductions were highest on the beetle bank itself. Three studies (Thomas 2001 and Macleod et al. 2004, summarised above, and Collins et al. 2003) found between 18 and 2,180 natural predators/m² in beetle banks between 1987 and 1998, including 11-423 ground beetles (Carabidae), 1-1,550 rove beetles (Staphylinidae) and 6-470 spiders (Araneae)/m². Predator numbers on beetle banks (maintained for up to 10 years) were similar to or higher than numbers in field margins. Another study (Holland et al. 2004) found total numbers of predators varied from 11 to 29 individuals/m² (in July and June respectively) in a cereal field without a beetle bank. In 2002 a beetle bank cost £975/ha to establish and £2/ha in income lost (with each subsequent crop) through land being occupied by the beetle bank (Collins et al. 2002).

    Additional references:

    Collins K.L., Boatman N.D., Wilcox A.W. & Holland J.M. (2003) A 5-year comparison of overwintering polyphagous predator densities within a beetle bank and two conventional hedgebanks. Annals of Applied Biology, 143, 63-71.

    Holland J.M., Winder L., Woolley C., Alexander C.J. & Perry J.N. (2004) The spatial dynamics of crop and ground active predatory arthropods and their aphid prey in winter wheat. Bullentin of Entomological Research, 94, 419-431.

    Thomas M.B. (1990) The role of man-made grassy habitats in enhancing carabid populations in arable land. Pages 77-85 in: N.E. Stork (ed.) The Role of Ground Beetles in Ecological and Environmental Studies, Intercept Ltd., Andover, UK.

Output references
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