Posted 11/17/2012 06:57 (#2701651 - in reply to #2701644) Subject: Re: Form of N on grass
NW Central Ohio
By the way, to answer the original poster's question. It isn't the kind of nitrogen that you get on...it's how soon you want it available to the plant. Ammonium nitrate has the nitrate form of nitrogen available to the plant as soon as it gets incorporated by rain on an established hayfield. If you use Urea, the urease has to convert to nitrate form before it's available, and in cooler soils that takes longer. Ammonia in Ammonium sulfate, and the ammonia component of Ammonium Nitrate...takes 2 steps to convert to the nitrate form of nitrogen, which extends it's effectiveness for your nitrate needs. I wouldn't hesitate to make a decision based on price per unit of nitrogen unless I needed some sulfur on a sandier soil in my hayfields.