The experienced field development scientist knows only too well how easy it is to be misled by relying too much on data generated exclusively from laboratory, greenhouse, or small plot field experimentation. This is because insects and plant diseases occur in populations of millions of individuals distributed spatially and temporally across a crop, according to their unique biological characteristics. While typical small plot studies can suggest parameters such as optimal usage rates and application intervals, trends must be validated through larger block studies where pest densities are more intensified and control capabilities of the new product are tested to their fullest. It is only through second stage large block testing that the manufacturer gains confidence in the new product and marketing efforts can begin to be formulated.