A crop takes up nutrients to build roots, stems, leaves and grain. Harvest removes only the nutrients in the material leaving the field. When straw or silage is removed, the export changes again. [2]
Count what leaves the field
This distinction matters for potassium. Much of the potassium taken up by some crops remains in vegetative tissue. A grain-only removal figure can therefore be much smaller than peak whole-crop demand. It is useful for a long-term balance, but it does not describe everything the growing crop needs. [3]
Build a removal estimate by multiplying harvested yield by an appropriate nutrient concentration or regional coefficient. Keep the units consistent: fertilizer phosphorus and potassium analyses are normally expressed as P2O5 and K2O, while research may report elemental P or K. [1] [3]
Keep removal separate from the recommendation
Removal coefficients are estimates. Variety, yield, nutrient concentration and the harvested fraction all change the outcome. A multi-year soil-test trend helps determine whether the replacement program is maintaining, building or drawing down fertility. [2]
The next crop’s fertilizer rate also depends on soil supply, residual nutrients, biological fixation where applicable and expected response. Replacing harvest removal one-for-one is not a complete annual recommendation, especially for nitrogen. [1]
Use a realistic yield target, a documented soil sample and a rotation-level budget. The objective is to meet current crop demand while understanding what each harvest does to the field’s nutrient reserves.
Related Taurus products and services
Use the current label and crop-specific guidance to check the product’s fit, rate, placement and compatibility.
Related Taurus video
Taurus Q&A: Soil Test Interpretation. This 2021 recording provides related agronomic background; use current labels for application decisions.
