Nitrogen content of rain water and that of leachates through quartz sand and two sandy soils of Florida were measured over a 3‐year period. Only NO3‐N was found in appreciable amounts. Annual rainfall of 45 to 50 in. contributed only from 2 to 3 lb N/acre. Leachates, from naturally occurring rain passing through Tavares and Placid fine sands, contained from 40 to 50 lb of N/ acre annually. Changes in soil pH and loss of base cations indicate that nitrification was taking place. Because there was little loss of organic N by the soils, atmospheric NH3is assumed to be the main source of N.