This document discusses two botanical pesticides - neem and pyrethrum. It states that neem has been found to be effective against approximately 200 insect pests, nematodes, and is particularly effective against various insects like grasshoppers, aphids, and caterpillars. It notes that pyrethrum is extracted from the dried flowers of the Chrysanthemum plant and that its active ingredients, pyrethrins, cause immediate paralysis in most insects at low doses and death at higher doses, while being non-toxic to humans and other warm-blooded animals. The document concludes that among various pesticidal plants, neem has been found to be the most effective.