If a fertilizer contains a slow release nitrogen source, it will be listed on the lavel. For urea formaldehyde-based fertilizers, the portion of the nitrogen that is slow-release is listed on the fertilizer bag as Water Insoluble Nitrogen (Win). If Win is not listed on the label, you should assume that all nitrogen in the fertilizer is in the quick-release form. For example, a fertilizer label might provide the following information.
| Guaranteed
Analysis Total Nitrogen ............................16% 8.5% Ammoniacal Nitrogen 2.00% Nitrate Nitrogen 5.5% Water Insolubule Nitrogen (WIN) Available Phosphate Acid (P205)........................ 4% Soluble Potash (K20) ......................8% |
| Because
the WIN is less than half of the total amount of nitrogen in the bag, this is a
quick-release fertilizer. %WIN x 100/ % total = % of total nitrogen that is Win or slow release nitrogen. Therefore: |
| Complete Survey 5.1 | Last Page | 10 |