Watering and Irrigation
Soil Moisture Replacement Calculator
The calculation of replacement depth depends on moisture deficit, root depth, and refill fraction. This page shows the relationship and a worked starting case.
Enter values for replacement depth
Soil Moisture Replacement needs moisture deficit, root depth, and refill fraction from one case.
Arithmetic used for Soil Moisture Replacement
Soil Moisture Replacement multiplies factors from Moisture deficit, Root depth, and Refill fraction to produce replacement depth. Compare this result with Tree Canopy Watering Calculator when water per event is also needed.
Soil Moisture Replacement evaluates moisture deficit at 0.12 in/in, root depth at 16 in, and refill fraction at 0.8 as 1.54 in.
Testing a change in moisture deficit
To compare alternatives, save the current result before changing Refill fraction. Label both cases so the source measurements remain clear.
Interpreting this replacement depth value
Replacement depth belongs to the Soil Moisture Replacement scenario. Recalculate replacement depth for another case.
Soil Moisture Replacement in practical terms
Soil Moisture Replacement focuses on Replacement depth and combines Moisture deficit, Root depth, and Refill fraction.
Use replacement depth to calculate water depth needed to refill part of a root-zone deficit, then inspect moisture deficit in the field.
Replacement depth: practical constraint
Do not irrigate beyond the soil intake and drainage capacity.
Before entering moisture deficit
Prepare Moisture deficit, Root depth, and Refill fraction for Soil Moisture Replacement. Keep unrelated records separate.
- Moisture deficit. Default in Soil Moisture Replacement: 0.12 in/in.
- Root depth. Default in Soil Moisture Replacement: 16 in.
- Refill fraction. Default in Soil Moisture Replacement: 0.8.
Documenting replacement depth
Store the Soil Moisture Replacement date, Moisture deficit, Root depth, and Refill fraction, and Replacement depth.
Separate measured moisture deficit from an assumed value so a later user can reconstruct the case.
Add the garden outcome as a new entry, using the same units and definition as replacement depth.
Soil Moisture Replacement low-and-high comparison
Raise Moisture deficit from 0.12 in/in to 0.132 in/in; keep root depth fixed. Replacement depth moves from 1.54 in to 1.69 in.
Soil Moisture Replacement isolates moisture deficit in this test; biological response remains outside the arithmetic.
If moisture deficit has a plausible range, save low and high cases instead of averaging the endpoints.
Replacement depth questions
How does “Do not irrigate beyond the soil intake and drainage capacity.” affect replacement depth?
Account for it in the source measurement for moisture deficit; the formula has no additional correction for it.
Does Soil Moisture Replacement adjust itself as crop demand changes?
No. Recalculate replacement depth after meaningful changes in weather, canopy size, root depth, or irrigated area.