inag 106 pesticide use & safety course david myers extension educator, agriculture...

INAG 106Pesticide Use & Safety Course

David MyersExtension Educator, Agriculture myersrd@umd.edu

Lecture 12: Pesticide Application & Calibration

PESTICIDE CALCULATIONS

Determine the amount of product neededFormulated Product vs Active Ingredient

Formulations and Active Ingredient

Dry formulations will report their active ingredient as a % by weightFor example the label for Thalonil states that it is a 90 DF productTherefore the active ingredient is 90% by weight of the containerIf the container weighs 5 lbs then .9 x 5 = 4.5 lbs of active ingredient

Formulations and Active Ingredient

Liquid formulations will report their active ingredient in lbs active ingredient per gallon and as % by weightFor example the label for Illoxan states that it is a 3 EC formulationThis means that there is 3 lbs of active ingredient per gallonIf the container size is 5 gallons then one would have 5 x 3 = 15 lbs of active ingredient

Formulations and Active Ingredient

For example Diuron 4L is a liquid formulationIts % active ingredient is 40%. To get the amount of active ingredient in a gallon one would have to multiply .40 by the weight of 1 gallon of this materialSince weight may not be given refer to the lbs A.I. / gallon statement

FORMULATED PRODUCT

The Label Contains Information On The Amount of Product Needed Under the “Directions For Use” Section

How much Aliette would you need to make up 450 gallons ifyou plan to use the lowest possible rate?

ANSWER

2.5 lbs 100 gallons =

x____ 450 gallons

Set up a proportion as follows and solve for x

(100) x (X) = (2.5) x (450)

X = (2.5) x (450) 100

X = 1125 100

X = 11.3 lbs of Aliette

Label Rate

ACTIVE INGREDIENT

DRY MATERIAL (% A.I. As a Decimal) (Form. Product) =

lbs of A.I.

LIQUID MATERIALlbs A.I = lbs A.I. Neededgallon formulated prod.

If you want to solve for the amount of active ingredient (A.I.) or if you are given the application rate in lbs A.I. then use one of the following formulas.

PRACTICE PROBLEMIf a 7.5 G insecticide is recommended at a rate of 4.5 lbs A.I./A, determine how much of the formulated product is needed to treat 4 acres?

Use this formula:

(% A.I.) x (lbs of Formulated Product) = lbs of A.I.

X = 60 lbs of product per acre

Remember you have to treat 4 acres therefore multiply 60 x 4 to get 240 lbs of insecticide for the 4 acre area.

(.075) x (X) = 4.5 lbs A.I.

X = 4.5 .075

% A.I. needs to be expressed as a decimal

PRACTICE PROBLEMA 13,300 sq. ft. area needs to be treated with Daconil 4F.How much Daconil 4F will be needed if you want to apply 3.5 lbs A.I.per acre.

Use the following formula for a liquid formulation:

4 lbs A.I. 1 gallon

= 3.5 lbs A.I. X

Solve for X :(4) x (X) = (1) (3.5)

X = 3.5 4X = .88 gallons of Daconil 4F is needed per acre

You need to treata 13,300 sq. ft. area

13,300 43,560

= .305 ofan acre

(.88 gallons) X (.305 acre) =.27 gallons of Daconil 4F willbe needed.

ACTIVE INGREDIENT

PERCENT CALCULATIONSDRY

(Gallons Spray) (% Spray) (8.3) % A.I. of PesticideLIQUID (Gallons Spray) (% Spray) (8.3) (lbs A.I. /Gallon) (100)

If you want to make up a % spray solution then the followingformulas can be used. One is for a dry formulation and the otheris for a liquid formulation

8.3 is a constant andrepresents theweight of 1 gallon ofwater

PRACTICE PROBLEMYou want to make up a 1.7% spray of Roundup 4 L. You have a 250 gallon sprayer which you plan to fill. How much Roundupwill be needed? How much water will be needed?

Use this formula to solve the problem :

( % Spray ) ( Spray Volume) ( 8.3) ( lbs A.I./gallon) ( 100 )

( 1.7 ) ( 250 ) ( 8.3) ( 4 ) ( 100 )

=

3527.5 400

=

8.82 gallons of Roundup 4 L will be needed

Amount of water needed =

[250 - 8.82] = 241.18 gallons of water and 8.82 gallons ofRoundup will be addedto give 250 gallons of spray

PRACTICE PROBLEMYou want to make up a .75% spray solution of Dursban 50 WP. How much Dursban will be needed if you want to make up a 30 gallons?

( % Spray) ( Gallons of Spray ) ( 8.3 ) (% A.I.)

Use This Formula :

(.75 ) ( 30 ) ( 8.3 ) 50

=

186.75 50

=

= 3.7 lbs of Dursban 50 WP

Note: When using thepercent mix formulasthe % spray and % A.I.

Values are not entered as decimals

PRACTICE PROBLEMS

1. If a 2.5G insecticide is applied at the rate of 3 lbs. A.I./A, how much of the formulated product is needed to treat5 acres?

Answer: 120 lbs/A and 600 lbs for 5 acres.

2. A 26,500 sq. ft area needs to be treated. The recommended application much of the formulated rate is 1.8 lbs A.I./A. The pesticide is formulated as a 2 EC. How much of the formulated material will be needed to treat this site?

Answer: .55 gallon or 70 oz

PRACTICE PROBLEMS

3. A 1.7% spray of Weedbgone 4L is required for excellent weed control. How much Weedbgone will be needed to treat a 2 acre field? Assume that you want to mix the product in water and apply the mixture at 1 gallon per 1,000 sq. ft.

Answer: 3.1 gallons

4.A fungicide, Nopatho 50 WP, is recommended at a 2 oz per1,000 sq. ft. rate on the label. How much Nopatho fungicide is needed to treat 1.75 acres?

Answer: 9.5 lbs

CALIBRATION EXERCISES

APRIL 25, 2005

CALIBRATION

The process by which one determines the application rate (gallons per acre or pounds per acre) of equipment under a given set of conditions.

APPLICATION EQUIPMENTMultipurpose Sprayers : Hand Held Units, Airblast Sprayers, and Spray BoomsBroadcast Applicators for Granular FormulationsBand or Row Applicators for Granular FormulationsSoil Fumigation EquipmentInjection and Implantation Equipment for Trees Greenhouse Applicators Can Range From Mists, Dusters, Drenches, to Foliar Spray Applicators

APPLICATION EQUIPMENT

Each Commodity Has a Separate Write Up in the Commodity ManualsAgricultural Manual : 10-15Ornamental and Turf Manual: Nursery and Landscape: 24-32 Turf : 40-43 Greenhouse: 51

WHY IS IT IMPORTANT TO CALIBRATE?

Damage was due to poor nozzle distribution.

Sprayer nozzles set too low thus causing a streaking effect.

SPRAYER CALIBRATION

FOUR VARIABLES THAT ONE CAN ADJUST TO GOVERN SPRAY OUTPUT ARE :1) NOZZLE TYPE 2) NOZZLE SPACING3) SPRAYER SPEED4) SPRAYER PRESSURE

CONSIDERATIONS IN NOZZLE SELECTION

Spray Product Catalogs Will Provide Important Information In Nozzle SelectionNozzle ConstructionNozzle PatternNozzle Spacing And Height Above Ground

Screen Which Is Placed BeforeNozzle to Prevent Plugging of Nozzle

Nozzle

Example of CatalogInformation on Nozzle Selection

CATALOG INFORMATION & INTERPRETATION65 Degree

Nozzle

80 DegreeNozzle

110 DegreeNozzle

ScreenMeshSize

Table Interpretation: For nozzle model 650067-SS it has the following characteristics : It is a 65 degree nozzle and can be used between 30 and 60 psi. If used at 50 psi it’s output would be .07 gallons per minute (GPM). Also at a 20 inch spacing and traveling at 5 MPH the application rate would be 4.5 gallons per acre (GPA).

PRODUCT CATALOG INTERPRETATION

Based on the previous slide answer the following questions:

1. What would be the GPM of nozzle model 8001-SS if used at 40 psi?

Answer: .1 GPM

2. If this nozzle is placed at a 20 inch spacing and a sprayer travels at 6 MPH what will its GPA be?

Answer : 5.0 GPA

CATALOG INFORMATION

NOZZLE TYPE SPRAYANGLE

NOZZLE HEIGHT

20”Spacing

30”Spacing

40”Spacing

The height of the nozzle above the spray boom is important so asto ensure uniform application. The table below shows the recommended height for different spray nozzles spaced at 20” to 40”.

NOZZLE CONSTRUCTION

BrassPolymerStainless SteelHardened Stainless SteelCeramic

Nozzles will wear differently based on their construction . Refer to the following slide on wear differences.

0 2 4 6 8 10 12

% INCREASE IN FLOW RATE AFTER 40 HOURS

Brass

Polymer

St. Steel

H. St. Steel

Ceramic

Brass nozzles wear much quicker than other types of nozzles.The ceramic nozzle wears the least.

This Sprayer Distribution PatternShows Good Coverage Across The Boom

This Spray Pattern Shows Worn Nozzles ; Greater Spray Under Each Tip Will Occur

NOZZLE PATTERN

Not every nozzle is created equal ! !MAJOR TYPES 1)Standard Flat Fan 2)Extended-Range Flat Fan 3)Even Flat Fan 4)Twin Flat Fan 5)Flooding Fan Nozzles 6)Full Cone 7)Hollow Cone

FLAT FAN NOZZLE

Jack of all tradesOperating Pressure : 30 - 60 psiAvailable in 65 , 80, and 110 degree anglesOverlapping is required for uniform applicationA preferred nozzle for herbicide application

EXTENDED-RANGE FLAT FAN NOZZLE

Similar to Flat Fan but with wider pressure range. 15-60 psi.

EVEN - FLAT FAN NOZZLE

Applies uniform amount across its spray widthUsed in band applicationsPressure requirement of 20- 40 psi and available in 40 or 60 degree spray angles

TWIN-FLAT FAN NOZZLE

Nozzle will have two openings ; 60 degree separationIncreases penetration into crop canopy30 to 60 psi

FULL CONE NOZZLEBest for pre-plant incorporated herbicides at the 15-25 psi range. Low pressure and large droplet size will reduce drift This cone nozzle is used for high volume applications40 inch spacing and nozzles need to be angled at 30 to 45 degrees from vertical to increase uniformity

HOLLOW CONE NOZZLE

Best suited for Postemergence herbicides. Can also do well for placement of insecticides, etc.Fits well into low volume applicationsDrop nozzle applications / 40-60 psi

FLOODING FAN NOZZLE “FLOODJET”

Create a wide deflector type flat spray patternLarger orifice reduces clogging10-40 psi range / 40” spacing

SPRAYER SPEED

Inverse relationship between speed and application rateAs speed increases application rate decreasesTo determine mph use the following formula : MPH = Distance Traveled (ft) x 60

Time (sec.) x 88

SAMPLE PROBLEM

Determine the mph if a sprayer travels 130 ft. in 40 seconds.

MPH = 130 x 60 40 x 88MPH = 7800/3520 = 2.2 mph

CALIBRATION TECHNIQUES

There are numerous methods used in calibrating sprayers. Several different techniques and formulas will be discussed in class

Calibration Tools

CALIBRATION:Method 1

Fill sprayer with water to set levelSpray known area noting pressure and speed settingsDetermine volume usedSet up an equality to solve for your application rate

•MeasureMeasure off known off known areaarea

CALIBRATION: Method 1Assume area measured off is 50 feet by 60 feet

50 x 60 = 3000 sq ft.

The volume used was 4 gallons then the equality is as follows …

4 gallons = x gallons3,000 sq. ft 43,560 sq. ft

X = 58 gallons per acre (GPA)

CALIBRATIONFORMULAS : Method 2

GPA = 5940 x GPM ( of nozzle) MPH x NW (nozzle spacing in inches)

GPA = 495 x GPM ( of sprayer) MPH x BW ( boom width in feet)

Conversion Factors

CALIBRATION

While the sprayer is running determine the nozzle output or boom output by collecting the spray and measuring the volume.

SAMPLE PROBLEMDetermine the GPA of a sprayer if given the following information. The nozzle out put averages .25 GPM and theyare spaced at 30 inches. The sprayer will travel at 6 MPH.

Using this formula one can solve for GPA :

GPA = 5940 x GPM MPH x NW

GPA = 5940 x .25 6 x 30

GPA = 8.25

SAMPLE PROBLEM

Determine the GPA of a sprayer given the following information :

The sprayer has 8 nozzles and each nozzle averages .5 GPM.The boom width is 12 feet and will be traveling at 4 MPH.

GPA = 495 x GPM MPH x BW

GPM is for the entire sprayer (8 nozzles). Therefore multiply 8times .5 to get the sprayer out put of4 GPM

GPA = 495 x 4 4 x 12

GPA = 41.3 or round off to 41

Farmer CalibrationOn-Line at: http://annearundel.umd.edu/files/SprayerCalibration.doc

Farmer Calibration

Farmer Calibration

DRY BROADCAST APPLICATION

Measure a Known AreaWeigh Product Before One Treats the Area and Note Spreader SettingReweigh After ApplicationSetup Equality

DRY BROADCAST APPLICATION

How much Insecto 5G will be applied per acre based on the following informationSpreader Setting LArea for calibration is 50 ft by 80 ft : 80x50 = 4,000 sq. ft.Amount of Insecto 5G placed in spreader was 90 lbs Area is treated and Insecto 5G is reweighed at 85 lbs. Difference = 5 lbsSet equality : 5 lbs = x 4,000 43,560Solve for x : (4000) (x) = (5) x (43560)

X = 54.5 lbs will be applied per acre

COMPUTERIZATIONSprayer Control SystemsAdjust Pressure and Speed to Deliver Desirable GPA Rates

Pictures From Teejet Web Page