Calibration and Calculations Made Easy for Turfgrass Applicators Fred Fishel, UF/IFAS Dept. of Agronomy S. Priest, UF/IFAS

orhttp://IFASbooks.ufl.edu

Learning Objectives 1.Describe methods for calculating the areas of different shaped sites. 2.Know how to calibrate application equipment by the area to be treated or by the amount of pesticide in the equipment. 3.Select nozzles for application equipment. 4.Check nozzles for uniform output. 5.Calculate travel speed. 6.Describe how to calibrate a granule spreader. F.M. Fishel, UF/IFAS

Application Error is Costly Wastes money Pest control failure Environmental damage Plant injury Legal penalties FDACS “Streaking” of a golf green from application error.

What is Calibration? F.M. Fishel, UF/IFAS

When to Calibrate? F.M. Fishel, UF/IFAS

Area Measurement Squares and rectangles Triangles Circles S. Priest, UF/IFAS Using a measuring wheel.

Area Measurement Squares and rectangles 230 feet 520 feet 230 x 520 = 119,600 ft 2 119,600 ÷ 43,560 = 2.75 acres

Area Measurement Triangles 270 ft 180 ft (180 x 270) ÷ 2 = 24,300 ft 2

Area Measurement Circles 68 ft 68 ÷ 2 = 34 ft 34 x 34 x 3.14 = 3,630 ft 2

Area Measurement Irregular shapes 68 ft 1,856 ft + 3,230 ft + 105,400 ft + 3,630 ft = 114,116 ft 2 or 2.62 acres 58 ft 32 ft 85 ft 76 ft 1,240 ft 85 ft

Safety F.M. Fishel, UF/IFAS

Equipment Choice S. Priest, UF/IFAS

Speed FDACS

Handheld and Backpack Sprayers T. Bowman, VA Tech Univ.

Calibrate by Area M.J. Weaver, VA Tech Univ.

Calibrate by Area 40 ft 65 ft 40 x 65 = 2,600 ft 2 Takes 80 seconds to cover 1,000 ft 2 Output is 57 oz per 1,000 ft 2 Equivalent to ounces per 2,600 ft ounces of herbicide needed to add to 143 ounces of water

Calibrate by Volume F.M. Fishel, UF/IFAS

Percent Dilution PercentageDecimal Equivalent 100% %0.10 2% %0.005 CDMS

Dilution Example To treat 18 azaleas: –Label rate of insecticide = 3 ounces per gallon –12 seconds to spray 1 azalea –10 ounces collected in 12 seconds –18 azaleas x 10 ounces = 180 ounces –180 ÷ 128 = 1.4 gallons –3 ounces x 1.4 gallons = 4.2 ounces

Dilution Example To mix 3 gallons of a 2% solution: –2 ÷ 100 = 0.02 –0.02 x 128 = 2.6 ounces –2.6 x 3 = 7.8 ounces UF/IFAS Pesticide Information Office

Dilution Example 0.25 ÷ 100 = x 128 = 0.32 ounces 0.32 x 3 = 0.96 ounces CDMS

Nozzles 4 main parts: –Body –Cap –Strainer –Tip F.M. Fishel, UF/IFAS

Nozzles Nozzle materials: –Brass –Plastic or polymer –Aluminum –Stainless steel –Ceramic S. Priest, UF/IFAS

Nozzles Spray pattern: –Cone –Flat fan UF/IFAS Pesticide Information Office

Nozzles T. Bowman, VA Tech Univ.

Nozzles S. Priest, UF/IFAS

Spraying Systems Co.

Spray Guns S. Priest, UF/IFAS

Spray Guns M.J. Weaver, VA Tech Univ.

Spray Guns M.J. Weaver, VA Tech Univ. 200 x 5 = 1,000 ft 2 Average time is 78 seconds Collect 5.25 gallons in 78 seconds 5.25 x = gallons per acre

Boom Sprayers T. Bowman, VA Tech Univ.

Nozzle spacing Nozzle height Spray angle Spray overlap Top of target N.C. State Univ.

Checking Spray Pattern UF/IFAS Pesticide Information Office

Checking Spray Pattern Streaks N.C. State Univ.

Checking Spray Pattern Photo source unknown

Acceptable Calibration Variation = +10% of the output EXAMPLE –Desired output = 15 gallons per acre (gpa) –15 x 0.10 = 1.5 – = 13.5 to 16.5 –An output between 13.5 and 16.5 gpa would be considered acceptable. S. Priest, UF/IFAS

Checking Nozzle Output Most agricultural sprayers have more than one nozzle. Possible source of variation. Do an output test to check for uniformity. 10% variation is ok. Spraying Systems Co.

Checking Nozzle Output Catch output from each of 4 nozzles for 30 seconds. –Nozzle 1 = 42 ml –Nozzle 2 = 48 ml –Nozzle 3 = 40 ml –Nozzle 4 = 39 ml Overall average = 42 ml

Checking Nozzle Output Overall average = 42 ml = 37.8 to 46.2 ml = acceptable range –Nozzle 1 = 42 ml = ok –Nozzle 2 = 48 ml = not ok, too much –Nozzle 3 = 40 ml = ok –Nozzle 4 = 39 ml = ok

Calibrating a Boom Sprayer Spraying Systems Co.

Measure Ground Speed T. Bowman, VA Tech Univ.

Measure Ground Speed What is the speed of a golf cart sprayer driven over a test run of 200 feet if three runs are timed at 40, 43, and 39 seconds? –( ) ÷ 3 = 40.7 seconds –40.7 ÷ 60 seconds per minute = 0.68 minutes per test run –200 feet ÷ 0.68 = feet per minute –Feet per minute ÷ 88 = mph –294.1 ÷ 88 = 3.3 mph

Collect Output GPA = (GPM x 5,940) ÷ (MPH x W) –GPA = gallons per acre –GPM = gallons per minute –5,940 = conversion factor –MPH = miles per hour –W = nozzle spacing in inches UF/IFAS Pesticide Information Office

Collect Output Will use a spray volume of 30 GPA MPH = 4.5 Nozzle spacing = 20 inches Average nozzle output = 0.44 GPM GPA = (0.44 x 5,940) ÷ (4.5 x 20) = 29 GPA

How Much Product to Add? Label rate = 5 pints per acre Area to treat = 2.5 acres Spray tank capacity = 200 gallons Sprayer output = 29 GPA M.J. Weaver, VA Tech Univ.

How Much Product to Add? 200 ÷ 29 = 6.9 acres 2.5 x 29 = 72.5 gallons 2.5 x 5 = 12.5 pints or 1.6 gallons of product 72.5 – 1.6 = 70.9 gallons of water M.J. Weaver, VA Tech Univ.

Rotary Spreader Calibration S. Priest, UF/IFAS

Rotary Spreader Calibration S. Priest, UF/IFAS

Rotary Spreader Calibration W. Buhler, N.C. State Univ.

Rotary Spreader Calibration W. Buhler, N.C. State Univ.

Rotary Spreader Calibration G.K. Jenkins, Design and Production, Raleigh, N.C.

P.A. Hipkins, VA Tech Univ. Distance/swath width to equal 1,000 ft 2 Swath widthLength needed 6 ft167 ft 8 ft125 ft 10 ft100 ft 12 ft83 ft CDMS

Rotary Spreader Calibration Label rate = 50 lbs Swath = 12 ft Beginning = 2 lbs Caught = 1.06 lbs Rate per 1,000 ft 2 = 1.06 lbs Rate per acre = 46.2 lbs UF/IFAS Pesticide Information Office

Rotary Spreader Calibration N.C. State Univ. CDMS

Rotary Spreader Calibration P.A. Hipkins, VA Tech Univ.

Photo/Diagram Credits University of Florida/IFAS FDACS Virginia Tech University N.C. State University Spraying Systems Co. CDMS G.K. Jenkins, Design and Production, Raleigh, N.C. Fred Fishel, Ph.D. Department of Agronomy University of Florida/IFAS Copyright 2008 University of Florida Mention of trade names in this presentation is solely for providing specific information. It is not a guarantee or warranty of the products named, and does not signify that they are approved to the exclusion of others of suitable composition. Use pesticides safely. Read and follow directions on the manufacturer’s label.