Abstract: The present invention provides a soil fertilization method which includes a process for producing a fertilyzer by-product from an ammonia filtering media. The method includes the steps of providing a filter media containing phosphoric acid soaked particles. In addition, the method includes providing ammonia laden air. The ammonia laden air is passed through the filter media to remove ammonia from the air which is removed by a chemical reaction which converts the phosphoric acid soaked wood particles to ammonium phosphate coated wood particles. After substantially all of the wood particles are converted to ammonium phosphate wood particles, the filter media is collected and then applied to soil to fertilize and build the soil.