Calibrating Nozzles

Frequency of Calibration

Even though a sprayer's operation can be theoretically determined using mathematical formulas, there are still many reasons to verify that the output is what it should be. For example,

  • wear (especially on nozzles)
  • damaged or malfunctioning parts (such as pressure gauges)
  • plugged or restricted passages (such as strainers and hoses)

Obviously, pre-season visual checks are not adequate for accurate application, nor is the fact that equipment and nozzle tips are new. Also, manufacturer's catalogs are only guidelines; fine-tuning a sprayer is the operator's responsibility.

A sprayer's output should be checked:

  • after any adjustments
  • when switching to a new chemical or application rate
  • after a week of continuous use under the same circumstances

Verifying the results of an adjustment is standard procedure for all John Deere products. Combine technicians would never make adjustments to a concave without then checking the hopper for cracked grain and the machine's path for grain passed on through. Likewise, you should never make adjustments to a sprayer without then verifying the output from the nozzles.

Cost Applied to Sprayers Combine Comparison
Wasted Resources Over-or-under application of expensive chemicals Loss of crop in field
Reduced Yield/Quality Chemical stress, pest pressure remaining Crop damaged in threshing operation
Effect on Future Crops Chemical carryover Volunteer crop next year
Custom Operator Fees Usually $4-$6/acre Approx. $12/acre

 

AG,OUO1011,845 -19-20JUL99-1/1