Once the population surveys are complete and proper spray threshold established, the spray blocks are designed.  With today's technology the spray blocks no longer need to be simple rectangles.  Now we design them to follow the homes, the habitat, and the gypsy moth concentrations.  Open areas and non-suitable habitats are eliminated  saving material and cost.  The down loads from the aircraft after the spray show the exact path of the aircraft and what exactly was treated.  This has been very useful in addressing home owner questions and concerns.