Early loss of nitrogen (N) this year may cause changes in types of N applied in future years, says Doug Ludwig, University of Missouri soil science graduate student who compared N performance by soils and drainage. He found:
On hills and higher ground, it's more cost-effective to use conventional urea.
In low-lying areas it was more cost-effective to use a slow-release fertilizer.
Slow release gave $80/acre more profit over conventional in low-lying areas.
Conventional urea gave $50/acre more profit over slow-release in well-drained areas.
Selective application may cost $10-12/acre more, but spreads two to three products in one field.