General principles governing the behaviour of granular formulations

Granular formulations are defined and a brief description is given of the most common methods used for their preparation. The physical behaviour of granules when applied to the soil surface is discussed in terms of uniformity of the treatment and release of toxicant by rain and by diffusion. The importance of granule size, toxicant content, application rate and granule density is considered and the way in which changes in these parameters are likely to affect the performance of granular formulations is illustrated.