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Nitrogen Calculator For Central Valley Crops

Created by Irfan Ainuddin, Patricia Lazicki and Daniel Geisseler*

The values calculated on this website are estimates based on literature data for N uptake. They are not recommendations. Weather conditions, management and variety selection all can affect N uptake and availability. It is therefore important to monitor the N status of the field during the season with soil or leaf analyses and to make adjustments to the fertlizer program.
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Basic Inputs: Field and Crop


The planting date is

The harvest date is

Estimated crop nitrogen (N) uptake and removal:

1. N in plant product:

2. N in product at harvest:

3. Total N uptake:

4. N in residue:

5. N removed at harvest:

Nitrogen Uptake Curve






Potential Nitrate Leaching Risks

6. Total N uptake:

7. Residual soil N:

8. N applied with irrigation:

9. In season N mineralization:

10. Required fertilizer N
     without leaching:

11. Water application efficiency
(The values below cover the range generally observed with the selected irrigation system):
12. N at risk of leaching:
13. Additional N to compensate for N leached: