Health, Safety and Environment - International Labour Organization

Manual 5:PESTICIDES AND HEALTH,SAFETY & THE ENVIRONMENTControlling pests on an organic farmInsect and disease control in organic agriculture is primarily preventativerather than curative. In addition to good husbandry and hygiene, the keyfactors of insect and disease control are: balanced rotational cropping to break the pest and disease cycles balanced supply of plant nutrients the creation of an ecosystem in and around the crop which encouragespredators, utilising, where appropriate, hedgerows or mixed plantbreaks within fields, companion planting, undersowing and mixedcropping the use of resistant varieties and strategic planting datesIn addition, permitted methods of pest and disease control includemechanical controls using traps, barriers and sound; herbal,homoeopathic and biodynamic sprays; waterglass (sodium silicate);bicarbonate of soda; soft soap; steam sterilisation; biological control withnaturally occurring organisms; and conventionally grown seed.If these do not provide sufficient protection, some organic standards alsocontain a number of 'restricted' methods. These include use of a number ofplant-based insecticides and fungicides, including natural pyrethrum androtenone.The key to pest control on organic farms is the system as a whole, ratherthan any individual steps. Chemical farmers say, quite rightly, that if theycut out all chemicals overnight, they would be over-run by pests. Theconversion period needed to qualify for organic food standards is not justset to 'detoxify' the soil of any agrochemicals, but is also necessary to allowthe growing area to come into nutrient balance again, build up predators,parasites and pathogens of pests, and so on.This does not mean that organic farmers never have problems with pests.They do, and then they resort to methods of pest control, which sometimesinclude the use of the small number of plant-based pesticides cleared foruse by certified organic producers. But organic farmers vastly reduce theneed for pest control, and thus also reduce the need for pesticides: organic farmers do not control pests where none occur. They do notpractise insurance, calendar spraying, which means spraying in case apest or disease should occur, (and which sometimes does more harmthan good by killing off the beneficial natural enemies of pests as well) they do not use cosmetic spraying, that is applying pesticide to makeproduce look better. People buying organic food would rather have say,harmless skin scabs on apples than synthetic pesticide residues withinthe apples organic farmers use non-chemical methods of pest control whereverpossible. This means that when they do have to resort to pesticides,such as pyrethrum and derris, in a genuine emergency, the pesticideshave a proportionately greater effect than when the land is routinelysoaked in agrochemicals267 Health, Safety and EnvironmentA Series of Trade Union EducationManuals for Agricultural Workers