Prilled Urea 46% contains 46% of nitrogen (N) in ureic form, simply absorbed by the leaves of plants. Absorption through the root system is slower, because urea in soil is transformed (like a results of enzymatic hydrolysis) into the ammonia form available for plants, and after that into nitrate form. https://tbookmark.com/story21365536/dap-fertilizer-msds-options