How does the Illinois calculator determine my phosphorus needs?
Overview:
The Illinois calculator can be used to help create phosphorus recommendations for your fertility strategies.
Requirements:
- Customers must be enrolled in Encirca® Premium Fertility service to use the Illinois calculator.
Answer:
The Illinois calculator utilizes the following equations:
Nutrient |
Crop |
Build/Maintenance |
Phosphorus |
Corn |
Bray P1: High Supply Power: If (STP * 2) < 40, P Rec = ((40 - (STP * 2) * 9 / 4) + (0.37 * Yield); if (STP * 2) > = 40 and (STP * 2) <= 60, then P Rec = (0.37 * Yield) Medium Supply Power: If (STP * 2) < 45, P Rec = ((45 - (STP * 2) * 9 / 4) + (0.37 * Yield); if (STP * 2) > = 45 and (STP * 2) <= 65, then P Rec = (0.37 * Yield) Low Supply Power: If (STP * 2) < 50, P Rec = ((50 - (STP * 2) * 9 / 4) + (0.37 * Yield); if (STP * 2) > = 50 and (STP * 2) <= 70, then P Rec = (0.37 * Yield) Mehlich 3-COL: STP = (0.84 * STP as M3-COL) + 1.21 Olsen Bicarbonate: STP = (2.27 * STP as Olsen) - 7.045 Mehlich 3-ICP: STP = (0.778 * STP as M3-ICP) - 6.4667 |
Phosphorus |
Soybeans |
Bray P1 or Mehlich 3-COL: High Supply Power: If (STP * 2) < 40, P Rec = ((40 - (STP * 2) * 9 / 4) + (0.75 * Yield); if (STP * 2) > = 40 and (STP * 2) <= 60, then P Rec = (0.75 * Yield) Medium Supply Power: If (STP * 2) < 45, P Rec = ((45 - (STP * 2) * 9 / 4) + (0.75 * Yield); if (STP * 2) > = 45 and (STP * 2) <= 65, then P Rec = (0.75 * Yield) Low Supply Power: If (STP * 2) < 50, P Rec = ((50 - (STP * 2) * 9 / 4) + (0.75 * Yield); if (STP * 2) > = 50 and (STP * 2) <= 70, then P Rec = (0.75 * Yield) Mehlich 3-COL: STP = (0.84 * STP as M3-COL) + 1.21 Olsen Bicarbonate: STP = (2.27 * STP as Olsen) - 7.045 Mehlich 3-ICP: STP = (0.778 * STP as M3-ICP) - 6.4667 |