A satisfying bug resource is available to on line at the Mana Whenua Landcare Research website which provides photos, basic facts and in some cases leads to more indepth info.
Landcare Research fields many enquiries about insects and other "bugs". The questions that are most frequently asked are:
What is this bug?
Where is it from, is it native or introduced?
What does it feed on?
Is it harmful?
Under an organic system, there are three general components of insect and disease management - cultural, biological and chemical. As Melissa Van Tine and Sven Verlinden say in their fact sheet Managing Insects and Disease Damage Under an Organic System, (PDF file) the conventional farmer may not know how to control pests and diseases without using chemicals. Their publication is aimed at giving people the information they need to escape reliance on chemical controls. Cultural controls include diversity, crop rotation, intercropping and strip cropping and planting dates. Biological control includes using organisms to keep pest populations at a suitable threshold while chemical control involves using naturally occuring chemicals as a last resort.
Before planting a crop, an organic vegetable grower needs to understand the pests and beneficial organisms that usually occur in that crop and anticipate the pest problems that are likely to occur. Experienced growers act before problems reach devastating levels because they know that pests are more effectively controlled when their numbers are low say the authors of Insect Pest Management for Organic Crops (PDF File). In this publication farm advisors and specialists from the University of California's Agriculture and Natural Resources division describe Monitoring for Pests and Beneficial insects along with cultural, mechanical, biological and chemical control.