Worksheet 2: Drill Spreader Calibration Calculation

Calculations to determine fertilizer weight (B) for the desired application rate:


____ A (lbs/acre) x____ C (rev) x _____D (ft) x _____ E (ft) ÷ 43,560 = ______ B (lbs)


____ A (kg/ha) x _____ C (rev) x _____ D (m) x _____ E (m) ÷ 10,000 = ______ B (kg)


= application rate (desired rate lbs/acre or kg/ha);

= weight of fertilizer (lbs or kg) collected from applicator(s) from one row during (C) revolutions

= number of the drive wheel revolutions

= “actual” drive wheel circumference (ft or m)

= row spacing (ft or m)

For further support please contact Haifa agronomist or mail us to

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