How does the Tri-State (Indiana, Ohio, Michigan) calculator determine my potassium needs?
Overview:
The Tri-State calculator can be used to help create potassium recommendations for your fertility strategies.
Answer:
The Tri-State calculator utilizes the following equations:
|
Nutrient |
Crop |
Build/Maintenance |
|
Potassium |
Corn |
Critical Value (CV) = 75 + (2.5 * CEC) If STK <= CV then K Rec = ((CV - STK) * (1 + (0.05 * CEC))) + (Yield * 0.27) + 20 If STK < (CV + 30) then K Rec = (Yield * 0.27) + 20 If STK >= (CV + 30) and STK < (CV + 50) then K Rec = (Yield * 0.27) + 20 - (((Yield * 0.27) + 20) * (STK - (CV - 30)) / 20) |
|
Potassium |
Soybeans |
Critical Value (CV) = 75 + (2.5 * CEC) If STK <= CV then K Rec = ((CV - STK) * (1 + (0.05 * CEC))) + (Yield * 1.40) + 20 If STK < (CV + 30) then K Rec = (Yield * 1.40) + 20 If STK >= (CV + 30) and STK < (CV + 50) then K Rec = (Yield * 1.40) + 20 - (((Yield * 1.40) + 20) * (STK - (CV - 30)) / 20) |
