Diatomaceous Earth – 4kg This product is best used in dry area’s of pens/runs. Sprinkle thru soil in area’s such as dust bath holes of poultry, sleeping holes of dogs. Under perches and thru bedding of chicken runs, including in nest boxes You may also dust animals directly sprinkling in coat and between feathers. This is not an instant fix but works by stopping the cycle of flea’s breeding in soil. Needs to be re-applied after rain and used routinely when cleaning pens.Diatomaceous earth is made from the fossilized remains of tiny, aquatic organisms called diatoms. their skeletons are made of a natural substance called silica. Diatomaceous Earth is not poisonous, it works by drying out and absorbing oils and fats from insects exoskeleton.