Determination of Contribution to Off-field Deposition from Multiple Swaths

Transcription

1 Determination of Contribution to Off-field Deposition from Multiple Swaths April 6, 217 Presented by John Hanzas on behalf of CropLife America 217 CLA and RISE Regulatory Conference 1

2 Study Objective The goal of this study is to evaluate the additive contribution to the downwind deposition profile resulting from multiple spray swaths. The test material (tank mix containing 2,4-D herbicide plus rhodamine tracer dye) was applied using two nozzles typically used in US agriculture, at two target wind speeds, and in accordance with EPA s DRT protocol (Final June 2). 2

3 Study Nozzles Two different nozzles were tested: Teejet XR114s at 43 psi and Teejet TTI114s at 63 psi. The XR nozzle (extended Range) is a flat fan nozzle with a spray pattern of 11 degrees and an 4 orifice size. The XR nozzles at this pressure produce a fine to medium spray quality, typically containing a relatively high percentage of driftable droplets. The TTI nozzle (Turbo Teejet Induction) contains air induction technology which entrains air bubbles within the spray droplets producing a coarser droplet. The TTI also has a spray pattern of 11 degrees and an 4 orifice size. The TTI nozzles at this pressure produce an extremely coarse to ultra coarse spray quality, typically containing a relatively low percentage of driftable droplets. 3

4 Spray Equipment and Calibration Sprayer: John Deere 47 series; 7 gallon spray tank Boom length: 6 feet Nozzles and spacing: 36 nozzles at 2 inch spacing Boom height: 2 inches, as recommended by the manufacturer Calibration was performed using SpotOn sprayer calibrators to determine the flow rate at each nozzle. Pressure was checked on the main gage and at the nozzle. Sprayer speed was calibrated. The results of the calibration were used to set the sprayer speed so that a constant rate could be used for both nozzles. 4

5 Wind Data Onset Computer Corporation Hobo data loggers that recorded air temperature, soil temperature, soil moisture, relative humidity, and solar radiation data. Wind speed and direction was recorded using a Gill WindMaster 3D sonic anemometer. Low and high target wind speeds of mph and 1 mph.

6 Tank Mix Weedar (2,4 D) at.lb/a rate Rhodamine WT fluorescent dye at.1% v/v 6

7 Collection of samples Sample collection platforms were set at 4 inches above the ground surface the height of field roughness. Sample collection was conducted by two person teams. 7

8 Study Conduct Five swaths were sprayed for each nozzle at two different wind speeds. Swaths were 6 feet wide by 3 meters long. High and low wind speeds were targeted for each nozzle. Multiple plots were set up to account for different forecasted wind directions and movement of the wind direction during the day. Deposition samples were collected on petri dishes at different distances from the edge of the spray area. 8

9 Title / landscape image / bullets above Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nunc ornare quam sed rutrum laciniamauris risus. enim, semper eget cursus lacinia, vehic Wind direction 9

10 Spray Video 1

11 Analysis of Deposition Samples 11

12 Study Results: Wind Most labels require applications to be conducted in 3-1 mph wind, not to exceed mph. The wind was not as cooperative as we would have liked. Target: One treatment at low wind ( mph) and one at high (1 mph). A treatment is a set of swath sprays: XR nozzles: Treatment 1 Average wind speeds ranged from mph Treatment 2 Average wind speeds ranged from mph TTI nozzles: Treatment 3 Average wind speeds ranged from mph Treatment 4 Average wind speeds ranged from mph Two replicated treatments of high wind. More conservative. 12

13 Results: Wind Data Treatment 1 (XR nozzle): Target Wind Direction: -7 Start Time End Time Pass Time (sec) Min Wind Speed (mph) Max Wind Speed (mph) Average Wind Speed (mph) Average Wind Direction ( ) Swath 1 11:27:38 11:28:39 :1: ± 1.7 ± 8 Swath 2 12:2:39 12::24 :2: ± ± 11 Swath 3 12:3:43 12:39:43 :4: ± ± 11 Swath 4 13:11:3 13:16:7 :: ± ± 11 Swath 13:4: 13:47:43 :6: ± ± 13

14 Results: Wind Data Treatment 3 (TTI nozzle): Target Wind Direction: -7 Start Time End Time Pass Time (sec) Min Wind Speed (mph) Max Wind Speed (mph) Average Wind Speed (mph) Average Wind Direction ( ) Swath 1 :4: :46: :: ± ± 8 Swath 2 16:11:29 16:13:32 :2: ± ± 7 Swath 3 16:32:46 16:3:2 :3: ± ± 1 Swath 4 7:24:24 7:28:7 :4: ± ± 4 Swath 7:48:21 7:4:1 :: ± ± 14

15 Study Results This data analysis is preliminary! All analysis at this point has been done in fraction of the applied rate. Future analysis will include percent of the applied mass. With this study design if the wind was exactly the same for each spray then the curves should show an increase in deposition until there is no further contribution. TTI nozzles had very low drift, as expected with a XC/UC spray quality. No detections beyond 32 meters. XR nozzle data had more drift and more variable wind. There curves are more difficult to interpret without using more advance statistical methods.

16 Results: Drift Curves by Deposition Distance m Treatment 3 TTI Nozzle Swath 2 1 Wind Speed (mph) m Treatment 3 TTI Nozzle Swath 2 1 Wind Speed (mph) Max wind speed Min wind speed Mean speed and Std Dev Max wind speed Min wind speed Mean speed and Std Dev m Treatment 3 TTI Nozzle Swath 2 1 Wind Speed (mph) m Treatment 3 TTI Nozzle Swath 2 1 Wind Speed (mph) Max wind speed Min wind speed Mean speed and Std Dev Max wind speed Min wind speed Mean speed and Std Dev 16

17 Results: Drift Curves by Deposition Distance 8 m Treatment 1 XR Nozzle 32 m Treatment 1 XR Nozzle Swath 2 1 Wind Speed (mph) Swath 2 1 Wind Speed (mph) Min wind speed Min wind speed Max wind speed Mean speed and Std Dev Max wind speed Mean speed and Std Dev 16 m Treatment 1 XR Nozzle 4 m Treatment 1 XR Nozzle Wind Speed (mph) Wind Speed (mph) Swath Swath Min wind speed Min wind speed Max wind speed Mean speed and Std Dev Max wind speed Mean speed and Std Dev 17

18 Results: Drift Curves by Deposition Distance 6 m Treatment 1 XR Nozzle 9 m Treatment 1 XR Nozzle Wind Speed (mph) Wind Speed (mph) Swath Swath Min wind speed Min wind speed Max wind speed Mean speed and Std Dev Max wind speed Mean speed and Std Dev 18

19 Results: Drift Curves by Downwind Distance 19

20 Acknowledgements Ralph Balko land owner / sprayer Hopkins Agricultural Services Sid Hopkins Greg Berger Bethany Berger University of Queensland Andrew Hewitt Stone Environmental Ben Brayden Brent Toth Sam Beguin Meghan Arpino Danny Moore CropLife America Imad Saab Dow Agrosciences Pat Havens Syngenta Crop Protection Mark Ledson Bayer CropScience Dan Dyer 2

21 21 Thank you!