Show tree tobacco insecticide the possibility that tree tobacco now a worthless weed in the arid sections of mexico and southwestern united states may become a valuable cash crop Is seen by united states scientists who have extracted from it a valuable insecticide sect icide the product was not discovered tn in the tree tobacco aen plant I 1 t u until rn 1835 1935 although it had been p pro deuced synthetically and fou found nd in an asiatic plant six years earlier than the first test in the ahe U S |