One way to eliminate trade in the illegal drug methamphetamine would be toeliminate one of its prime ingredients. Iowa Senator Tom Harkin is hoping todo just that.Harkin is calling on USDA to initiate a research project to chemically alteranhydrous ammonia to render it useless to meth producers. Besides being usedto make meth, that chemical is used by farmers in fertilizing their fields.Harkin says the scientific work to defeat meth dealers is already underwayin central Iowa.Farmers across Iowa & elsewhere are seeing their anhydrous tanks broken orstolen by meth makers.