(Mason, MI)  --  The Ingham County Sheriff's Department said a 70-year-old farmer caught a man trying to steal anhydrous ammonia from his farm.  Anhydrous ammonia is used as a fertilizer, but it is also a key component in making meth.  Police said the farmer held the 23-year-old suspect at gunpoint in the middle of the blizzard with a handgun until police arrived to arrest him.  The suspect had a plastic thermos with him, which is also commonly used by meth cookers to transport the fertilizer.