Pesticides and herbicides are applied to crops via complex formulations in the form of aerosols of single or multi phase liquids. The stability of the formulation both in its bulk form and as aerosol during application is related to interfacial properties. The wetting and spreading of aerosol droplets on plants is directly proportional to its effectiveness. New laws (e.g. REACH) and concerns about ecological footprint drive the search for increasingly environmentally friendly agricultural chemicals.