Prilled Urea 46% contains 46% of nitrogen (N) in ureic form, easily absorbed by the leaves of plants. Absorption through the foundation system is slower, because urea in soil is converted (as being a results of enzymatic hydrolysis) into the ammonia form available for plants, and afterwards into nitrate form. https://az-directory.com/listings13629994/npk-fertilizer-with-6-6-6-or-10-10-10-options