Field Test Comparisons of Drift Reducing Products for Fixed Wing Aerial Applications Robert E. Wolf, Kansas State University, Manhattan, Kansas • Scott Bretthauer, University of Illinois, Urbana, Illinois • Dennis R. Gardisser, University of Arkansas, Little Rock, Arkansas

ABSTRACTTen drift control products were compared for reducing horizontal and vertical drift for a high-speed fixed wing aerial application scenario. Water-sensitive paper and DropletScan™ software was used to collect and compare the differences in drift.• Differences in amounts of drift were found among

all treatments.• A few of the products exhibited less drift potential

than water alone.• Several of the products exhibited the same or

more drift potential than water alone.• Slight differences were measured in how the

products affected the droplet size (VMD).

INTRODUCTIONOff-target drift is a major source of application inefficiency. Application of crop protection products with aerial application equipment is a complex process. In addition to meteorological factors, many other conditions and components of the application process may influence off-target deposition of the applied products. Spray formulations have been found to affect drift from aerial applications. Materials added to aerial spray tank mixes that alter the physical properties of the spray mixture affect the droplet size spectrum. With new nozzle configurations and higher pressure recommendations, and with the continued development of drift reducing tank mix materials, applicators seek to better facilitate making sound decisions regarding the addition of drift control products into their tank mixes.

OBJECTIVEThis study evaluated the influence of selected drift control products/deposition aids on horizontal, vertical, and total spray drift during a high-speed fixed wing aerial application scenario.

• AT 501A Drop booms CP-11TT #15 nozzles w/8° deflection 44 psi 156 mph ground speed by radar

• Droplet Spectrum: Medium (CP/USDA Model)• Percent Volume < 200 microns = 7.65%• Aircraft calibrated for 28 L/ha (3 GPA)

Product Name Company Mixing Ratea

Tap water 1 Local supply X-77 onlySuperb HC +

InterlockWinfield Solutions

133 oz + 33 oz / 50 gal

Formula 1 United Suppliers 1.5 qt / 50 gal#PX056-Z Precision Labs, Inc 5 qt / 50 gal

Tap water 2 Local supply X-77 onlyAg 06037 Winfield Solutions 64 oz / 50 galAg 08050 Winfield Solutions 80 oz / 50 gal

Interlock 1.25 Winfield Solutions 80 oz / 50 gal

ControlGarrCo Products,

Inc2 oz /50 gal

Tap water 3 Local supply X-77 onlyINT 908 Rosen’s 5 gal / 45 gal

Tap water + Prime Oilb

Local supply + Winfield Solutions

266 oz / 50 gal

Interlock 0.8 Winfield Solutions 50 oz / 50 gal

a All tank mixes included X-77 at .25% v/v (16 ounces per 50 gallon load).

b Oil to simulate a suggested tank mix with fungicide (Prime Oil @ 1 pint/acre).

CONCLUSIONS Differences in coverage representing downwind drift were measured at all horizontal and vertical collector

positions for all the treatments.

INT 908, Control, and Interlock 0.8 all were measured with significantly less drift than the average of the three all water treatments.

A water and oil treatment also had less drift than the average of the water treatments.

The remainder of the products were measured with more drift than the water only average.

Based on mixing, loading, and system cleanout evaluations, some products may hinder good application techniques.

RESULTS

Figure 3. Treatment volume median diameter’s.

Figure 4. Horizontal drift summary.

0200400

374 380 398 393 345 331 333 348 336 368 356 347 379

Mic

ron

Size

Figure 6. Total drift summary.

0.020.040.060.0

44.2 50.2 42.9 47.7 42.7 54.0 55.841.1 33.9 39.8 32.9 35.7 35.1cde

efbcde def bcde

f fabcde ab a

0.0

10.0

20.0

5.911.3 10.5

15.7 15.0 17.4 18.812.8

3.8 4.2 3.7 5.9 2.7

Figure 5. Vertical drift summary.

0.0

40.0

80.0

50.1 61.5 53.3 63.5 57.771.4 74.6

53.937.7 44.1 36.5 41.6 37.8

0.0

20.0

40.0

60.0

80.0

36.5 37.7 37.8 41.6 44.1 50.1 53.3 53.9 57.761.5 63.5

71.4 74.6

Figure 7. Total drift rank.

water average

Volume Median Diameter

Horizontal Drift

Vertical Drift

Total Drift

Ranked Total Drift

Figure 1. Air Tractor 502A.

Figure 2. Horizontal and vertical drift collection towers.

• Three vertical towers extended 40 feet and located 300 feet downwind from the flight line.

• WSP positioned at 5-foot increments up the tower.• WSP on horizontal collectors located on 50-foot increments away from

flight line and toward the towers.

Vertical Towers

Horizontal Collectors

Flight Line

% A

rea

Cove

rage

% A

rea

Cove

rage

% A

rea

Cove

rage

% A

rea

Cove

rage

EQUIPMENT AND PRODUCTS