Calibrating sprayers involves selecting the proper nozzles, spraying pressure, and speed of travel. There are several different ways to accurately calibrate a sprayer, but the simplest is the 1/128th acre (340 sq.ft.) method, also called the “baby bottle” method. The spray collected from a single nozzle measured in ounces directly converts to gallons per acre regardless of the number of nozzles on the boom. Because there are 128 ounces in a gallon, the ounces collected from 1/128th of an acre will equal gallons of solution per acre.
Follow the 10 easy steps below to avoid needless chemical waste, improper application, and potential turf injury.
Nozzle spacing and distance chart for 1/128th acre. | |
Nozzle Spacing (in) | Distance (ft) |
6 8 10 12 14 16 18 20 22 24 26 28 30 | 681 510 408 340 292 255 227 204 186 170 157 146 136 |
For a backpack or other single nozzle sprayers this same method will still work. Simply determine the width of the spray pattern to get the distance. Or, fill the sprayer completely with water then spray an area equal to 340 sq. ft. (20’ x 17’). The ounces of water required to refill the sprayer will equal gallons per acre.
Published March 16, 2009
Dr. Wayne Wells is an Extension Professor and Turfgrass Specialist. His mailing address is Department of Plant and Soil Sciences, Mail Stop 9555, Mississippi State, MS 39762. wwells@ext.msstate.edu