Environmentally friendly spray techniques for tree crops

Environmentally safe spray techniques have been developed to use minimal pesticide inputs and apply them only when and where needed with reduced losses to the environment. In this paper, two such systems are described: (1) shielded systems that recycle spray liquid that would otherwise be lost; (2) detection systems that recognise where there are gaps in crop rows for which spray is not needed. The results of studies by several research groups prove the relevance of these sprayers in reducing pesticide losses. Shielded spraying allows a reduction in chemical input in orchard protection by up to 85% by exploiting more uniform in-canopy spray distribution, recycling the spray that would otherwise be wasted. Sprayers with target detection systems apply spray only where target trees or bushes are present. This technique can reduce chemical consumption in orchards by 30% and decrease drift by 50%. (C) 2000 Elsevier Science Ltd. All rights reserved.