1. Mark off a 1,000-square-foot area (10 feet by 100 feet or 20 feet by 50 feet).
2. Time (in seconds) how long it takes to spray this area using your normal spraying procedures.
3. Spray into a 5-gallon bucket for the same amount of time. Make sure to use the same spray pressure.
4. Measure the amount in gallons.
5. Multiply the number of gallons by 43.56 to get the gallons per acre.
Example: It takes you 25 seconds to spray 1,000 square feet. When you spray into your bucket for 25 seconds, you measure 2.5 gallons. This amount times 43.56 equals 108.75 gallons per acre.