Robert E. Wolf Associate Professor - Extension Specialist Application Technology

Robert E. Wolf

Associate Professor - Extension Specialist Application Technology

Biological and Agricultural Engineering

Application StrategiesCalibration….Calibration….

Top Farmer Crop WorkshopPurdue University

July 20, 2009

Accurate and efficient applications:Increase Efficacy – Minimize Drift

Calibration!!!!

Ensuring that the spray output is what it is supposed to be!

Calibration/Nozzle Selection:

• What is the first step?• Use label to select the

– application volume– product rate

• Choose an appropriate travel speed - MPH

• Effective width of application– nozzle spacing

• Calculate GPM – Flow rate per nozzle

• Select the correct size of nozzle!

Rate Controllers:Rate Controllers:

Parallel Swathing – light bars:

Auto Steering:

Automatic Boom Height Control

Automatic Boom Section Control

Improving Coverage?

Courtesy of Ken Giles, U of California Davis

Calibration!!!!The next phase!

Ensuring that the spray droplet spectrum is what it is supposed to be to maximize

efficacy while minimizing drift!

ASABE S-572 Droplet Size Standard

Spray quality categories.

ASABE Standard S-572.1Category (symbol) Color Code

Extra Fine (XF) Purple

Very Fine (VF) Red

Fine (F) orange

Medium (M) yellow

Coarse (C) Blue

Very Coarse (VC) Green

Extra Course (XC) White

Ultra Coarse (UC) Black

2009

Source: Crop Life – July 2002

>150

151-250

251-350

351-450

451-550

>551

ASABE Standard

Page 4

See Page 182, TeeJet Catalog 50A

Droplet Selection/Calibration:

p. 15

Greenleaf Droplet chart:

What is the ‘Real’ difference ?

……Medium droplet at 225 microns

……Coarse droplet at 300 microns

How much heavier? Or is it???

300 = 1.33

2251.33 bigger

1.333 = 1.33 * 1.33 * 1.33 = 2.35

2.35 * 100 = 235% heavier

Drift Reduction Additives:

• Many available!• Not EPA regulated• Long chain polymers• Soluble powders• 50 - 80% reduction in off-

target movement• Not all will work!!!!• Pump shear problems• Effect on the pattern?

Volume Median Diameter (VMD)

050

100150200250300350400450500

11004XR 11004TT TF 2 11003AI

Mic

rons

Water RWM + 2%AMSRWM + 1% AMS + Array RWM + 2% AMS + BorderRWM + 2% AMS + Placement

40 psi 40 psi 40 psi 70 psi

% less than 210 Microns

37 51 36 35 45 23 30 14 15 26 19 22 14 13 22 10 17 29 29 15

Bob Klein, U of Nebraska

Percent fines

Disclaimer:

• Brand names appearing in this presentation are for identification and illustration purposes only.

• No endorsement is intended, nor is criticism implied of similar products not mentioned.

www.bae.ksu.edu/faculty/wolf/

For more information contact:

rewolf@ksu.edu