Providing evidence to improve practice

Individual study: Role of hedgerows and ground cover management on arthropod populations in pear orchards

Published source details

Rieux R., Simon S. & Defrance H. (1999) Role of hedgerows and ground cover management on arthropod populations in pear orchards. Agriculture, Ecosystems & Environment, 73, 119-127

This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Allow natural regeneration of ground cover beneath perennial crops Natural Pest Control

A controlled study in a pear Pyrus communis orchard in Drôme, France (Rieux et al. 1999) found that the ratio of beneficial to plant-eating invertebrates was similar in pear tree canopies over naturally regenerated (0.05 natural enemies to each pest), bare (0.04 natural enemies) and sown (0.06 natural enemies) ground covers. Flies (Empididae), leaf bugs and plant bugs (Miridae) were the most numerous enemies in trees over regenerated ground covers. Similar numbers of natural enemies were found in regenerated and sown plants on the ground. However, regenerated plants had nearly two times more plant-eating invertebrates than sown plants so there were 0.06 natural enemies to each pest in the former vs. 0.09 natural enemies to each pest in the latter. More natural enemies (for each pest) occurred in regenerated plants than in the tree canopies. Natural ground cover (established for 10 years), bare ground (created with glyphosate in March 1994) and sown ground cover treatments (planted in September 1993) each occupied one-third of the orchard (five rows between trees). Sown ground covers comprised ryegrass Lolium perenne, white mustard Sinapis alba and white clover Trifolium repens. Insects were sampled by beating branches in trees and using a sweepnet in ground covers.