In one embodiment, the present invention relates to a pesticide delivery system, containing a continuous film having a thickness from about 1 m to about 1,000 m and noncontinuous areas having sizes less than about 100 m, the continuous film containing a particulate material wherein at least 90% by weight of the particulate material has a particle size of about 10 microns or less, and a pest control agent at least partially coating the particulate material. In another embodiment, the present invention relates to a method of delivering a pest control agent to a target organism, involving the steps of applying to at least a portion of a surface of a plant an effective amount of finely divided particulate material at least partially coated with the pest control agent, the particulate material containing from about 25% to about 100% by weight of a heat treated particulate material, wherein the partially coated finely divided particulate material as applied permits an exchange of gases on the surface of the plant and the partially coated finely divided particulate material forms a continuous film over the portion of the plant surface to which it is applied, and a maximum average size of openings in the continuous film is less than about 100 m.