NATURAL PYRETHRUM oil is extracted from the Pyrethrum daisy and been used as a natural insecticide since the early 1900â€™s. It has been proven to be one of the most environmental friendly low toxic insecticides as there is virtually no residue. Sharp Shooter Natural Pyrethrum Insect Spray is best applied at sunset to avoid contact with bees, as they have then gone back to their hives. Application at sunset is very effective as the product may break down in direct sunlight. Insects cannot build up immunity because of the complexity of its natural molecules. It is an effective contact insecticide with immediate knock down and controls a wide range of insect pests including caterpillars. It is very safe for humans on fruit and vegetables as it only has a one day withholding period before they can be consumed.