Pyrethrum is a vegetable insecticide made from oils found in the plant Chrysanthemum cinerarifolium. It is very effective in killing aphids, ants, mosquitoes, flea beetles, weevils, sawfly caterpillars, leaf hoppers and many other insects. It works very quickly but only if the bug is in contact with the spray or powder. It loses it’s toxicity quite rapidly under sun and air. The EPA has widely approved it as the safest insecticide on the market. It also has been known to cause allergic reactions so wear gloves and wash well if you feel you need to use this substance.
Chrysanthemum cinerarifolium (Pyrethrum)-NCSU Horticultural Science