Show tropical insecticide Is found F in amei ican weed the th devils shoestring a common weed in the eastern halt half of the united states contains rotenone a valuable insecticide formerly found only to in tropical plant a united states department of agrical chemist has found tho the discovery la Is significant for farmers both as potential growers of the plant and as users usera of the insecticide sect icide to insecticide manufacturers and to importers portera liu who carry on the tha international trade in rotenone and other insecticides dr W IV skinner assistant chief of the chemical and technological research unit of via the bureau of chem chein astry and solli ferit called attention to the probable value of devils devil s shoestring following his observation 8 C that bees and er insects led fed on nearby plants but avoided the blooms of this toxic weed eed dor tor skinner later instigated the research which led to the recent discovery of this weeds weed a rotenone content by dr E P dark clark of the bareau a insecticide division although the alue of devils shoestring was demonstrated bout about it two years ngo ago by prof V A I 1 ittle of th the texas agricultural college vilo rho found it effective against various species i of insects its value as 03 tt source of lo lot enone was not known until ironed by the department a research |