Individual study: Intercropping cabbage with clover results in a higher carabid abundance
Wiech K. & Wnuk A. (1991) The effect of intercropping cabbage with white clover and French bean on the occurrence of some pests and beneficial insects. Folia Horticulturae, 3, 39-45
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Plant more than one crop per field (intercropping)
A replicated, controlled, randomized study from 1985 to 1990 of a cabbage crop in Poland (Wiech & Wnuk 1991) found that intercropping with white clover Trifolium repens resulted in a higher abundance of ground beetles (Carabidae). The total number of ground beetles was greater in intercropped cabbage Brassica oleracea and clover plots (2,528) than those with cabbage alone (1,753). This was the case for Amara aulica (16 individuals vs 52), Calathus fuscipes (105 vs 199), Harpalus rufipes (586 vs 920), Pterostichus cupreus (110 vs 305), P. vulgaris (13 vs 53) and ‘other species’ (360 vs 547), but not Bembidion properans (452 vs 563). There was no association between increased cover and predator diversity. White clover was sown in 30 m² plots in May on a four replicated block design. Cabbage was sown between the rows within plots in June. Ground beetles were sampled with two pitfall traps in the centre of each plot. Samples were collected weekly through the growing period. Aphid (Aphidoidea) abundance and damage by the cabbage moth Mamestra brassicae was also sampled.