Provide somewhere for your hens to have dust baths. A deep tray filled with dry riddled soil or a bag of standard compost is adequate. Do not use sharp sand because this can hurt their eyes and irritate their skin. For dusting, the substance should be very light, fine, and dry. The finer the better. Being designed to kill lice, it must be fine enough to fill the breathing pores of these parasites.
Sandy loam mixed with road dust makes a fairly good dusting material. If sand or road dust is used, sifted coal ashes aid in making it finer. The dust box should be placed where sunlight can shine into it, and must be kept free from all litter and other foreign matter.
A dust bath is as necessary for the health of chickens as a water bath is to the health of many other animals. By dusting itself the bird can rid itself of lice and remove all the scales and dirt from the skin.