Nitrogen even application
Uneven application of nitrogen fertilizer is a longstanding problem that is getting worse. The main causes of uneven N application are:
- Anhydrous ammonia manifolds that distribute N unevenly to knives.
- ‘Dusty’ dry N fertilizer (urea or ammonium nitrate) spread with spinner spreaders. This problem is getting worse due to increasing imports of dry N fertilizer, leading to more handling (augering) and breakdown of prills or granules into smaller pieces. The smaller pieces can’t be spread as far as larger ones, and N rate is higher in and near the applicator path. Even when fertilizer is intact going into the spreader, it may break into smaller pieces when the spreader vanes hit it, causing similar problems with small particles that will not travel far enough.
- Even when dry fertilizer quality is good, we have found uneven patterns using catch pans in commercially-applied fields. Spinner spreader mechanisms need to be tested and adjusted to give the correct spread pattern.