Table 2. DRY CHEMICAL APPLICATOR CALIBRATION: ALTERNATIVE PROCEDURE

 1. ADJUST DELIVERY OPENINGS ON APPLICATOR TO ESTIMATED OR APPROXIMATE SETTING
 AND FILL HOPPER WITH A WEIGHED AMOUNT OF CHEMICAL TO BE APPLIED.

 2. JACK UP APPLICATOR SO THAT WHEELS DO NOT TOUCH THE GROUND. TIE A PIECE OF
 CLOTH (or paint) TO ONE SPOKE OF WHEEL.

 3. PLACE A PIECE OF CANVAS OR SHEET METAL UNDER THE DELIVERY OPENINGS TO
 CATCH THE CHEMICAL WHEN IT IS DISPENSED.

 4. OPEN SHUT-OFF CONTROL TO PERMIT THE CHEMICAL TO FLOW AND MAKE 43 COMPLETE
 REVOLUTIONS OF THE DRIVE WHEELS.

 5. SHUT OFF FLOW FROM HOPPER AND WEIGH THE CHEMICAL DELIVERED DURING THE 43
 DRIVE WHEEL REVOLUTIONS.

 6. CALCULATE THE AMOUNT OF CHEMICAL DISCHARGED ON A PER ACRE BASIS WITH THE
 FOLLOWING FORMULA:

 POUNDS PER ACRE POUNDS DISCHARGED x 1000
 DRY CHEMICAL SPREADER WIDTH feet) x WHEEL CIRCUMFERENCE (feet)


 THIS VALUE WILL BE POUNDS PER ACRE OF FORMULATED CHEMICAL APPLIED. TO DETER-
 MINE AMOUNT OF ACTIVE INGREDIENT APPLIED MULTIPLY POUNDS PER ACRE ABOVE
 BY PER CENT ACTIVE CONCENTRATION AND DIVIDE BY 100, AS FOLLOWS:

 POUNDS PER ACRE ACTIVE = pounds per acre formulated chemical x % act.
 100
 7. RATE OF APPLICATION IS INCREASED BY WIDER DELIVERY OPENINGS

 8. RATE OF APPLICATION IS DECREASED BY NARROWER DELIVERY OPENINGS.

 9. COMPLETE CALIBRATION BY ADJUSTING UNIT AND TESTING UNTIL DESIRED QUANTITY
 OF MATERIAL IS APPLIED.

10. CHECK CALIBRATION BY OBSERVING AMOUNT OF CHEMICAL APPLIED TO A FIELD OF
 IGKOWN ACREAGE.

 Example: A dry chemical applicator is jacked up and the drive wheel
 is turned through 43 complete revolutions. The wheel cir-
 cumference is 9 feet and the spreader width is 8 feet. The
 chemical delivered in 43 wheel revolutions is 29 pounds.

 Pounds per acre dry chemical = 20 x 1000 = 277 lb/A
 8' x9'
 If the chemical contains 2001 active ingredients:

 Pounds active ingredient per acre = 277 x 20 = 55.4 lb/A
 100