2008 Annual Report
1a.Objectives (from AD-416)
1)Development of technology for optimizing drift-measurement techniques;.
2)Development of technology for improved drift management and pattern uniformity associated with aerial application; and.
3)Development of technology for remote sensing and variable-rate aerial application.
1b.Approach (from AD-416)
This project seeks to advance application technology through improvements in 1)drift measurement technology, 2)drift management technology, 3)the use of low-altitude remote sensing to identify weed pests and preferred habitat for insect pests, and 4)the performance of variable rate systems for aerial application.
Drift measurement techniques are proposed that account for varying environmental conditions existing during the implementation of a drift study. Techniques that do not confound treatment data with environmental effects will be examined.
While drift management is a concern for all pesticide applications, it is of particular concern for aerial applications. The potential for drift is greater for aerial application due to higher heights of spray release and greater air turbulence in the wake of the aircraft. Turbulence also tends to disrupt the pattern of spray deposit in the wake of the aircraft. A study is proposed that uses video assessment to evaluate the effects of air turbulence on spray released from specific points of interest in the vicinity of the spray boom. Particular emphasis will be given to identifying the zones of influence associated with wing-tip vortices and the propeller slipstream. Results of the study will provide guidance for nozzle placement to minimize the effect of the propeller slipstream and wingtip vortices. Techniques are proposed for improving remote sensing by using digital video and high resolution digital cameras on low altitude platforms to discriminate weeds from crop and wild host plants attractive to insects. Multispectral data from low altitude platforms will also be used to detect time and locations within a cotton field for terminating insecticide applications. A variable rate aerial application system is proposed that will be improved through interaction with system component manufacturers. Techniques for processing and analyzing remote sensing data are proposed to enhance conversion of remote sensing data to application prescriptions in near-real time. Experiments are also proposed to demonstrate the validity of techniques developed.
A field study was conducted to provide preliminary data on off-target spray drift and penetration of spray into soybean canopies. Three nozzle/atomizer setups were evaluated for droplet size/spectrum and their potential to penetrate spray into the lower levels of a soybean canopy. Three spray application heights precisely determined by laser were selected and the airplane was flown in two directions to account for the effects of propeller wash direction on spray deposition. Efforts were made in the experimental design to reduce environmental effects from treatment effects. Results indicated the greatest coverage was observed with a high coverage nozzle and best uniformity of droplet size with a rotary atomizer. Analysis of spray drift as recorded on Mylar samplers is continuing. These experiments served to provide preliminary data for a proposed larger study that will also substitute flat-fan nozzles for the standard deflector nozzles as one treatment in the study. Droplet sizes from all three nozzle/atomizer types will be matched more closely to a low-medium spray category beforehand by aerially spraying onto water sensitive cards placed in the spray swath of a grass field. Further testing of variable-rate aerial application system response was also accomplished. Issues were noticed in flowrate tracking that required diagnosis by the flow control system developer and project cooperator. Upgrade of the flow control program by the system manufacturer has been based on field evaluations conducted by the scientists.
This work addresses National Program 305, Component 1: Integrated Sustainable Crop Production Systems; Subcomponent 1A: Annual Cropping Systems; Problem Statement 1A.2: “Develop Automation and Mechanization Systems and Strategies to Optimize Pest Management, Improve Crop Yield and Quality, Reduce Worker Exposure, and Protect the Environment While Maintaining a Profitable Production System.”
Thermal imagery was analyzed using spatial statistics to define areas of crop water stress in cotton and to determine areas of variable soil texture as verified by the VERIS 3100 Soil EC Mapping System. Thermal imagery was able to correlate well with differences in yield, and areas of significant correlation were mapped.
NP 305, Component: 1, Problem Statement: 1A.4.
The spray study demonstrated that a high coverage radial nozzle used primarily for forestry applications provided better spray penetration into a soybean canopy than other nozzles or atomizers tested, even though the rotary atomizer exhibited the narrowest range of droplet sizes.
Narrow droplet spans would have implications for mitigating off-target spray drift, and analysis of spray drift is continuing with the partial data sets obtained (wind direction permitting).
This accomplishment addresses National Program 305, Component 1: Integrated Sustainable Crop Production Systems; Subcomponent 1A: Annual Cropping Systems; Problem Statement 1A.2: “Develop Automation and Mechanization Systems and Strategies to Optimize Pest Management, Improve Crop Yield and Quality, Reduce Worker Exposure, and Protect the Environment While Maintaining a Profitable Production System.”
Trends derived from thermal imagery were successfully correlated with crop stress and soil texture using spatial statistics and in-field instruments that evaluate plant and soil variables.
Successful identification of soil texture from conveniently scheduled aerial platforms can greatly reduce the time required to identify zones requiring variable management according to soil type.
This accomplishment addresses National Program 305, Component 1: Integrated Sustainable Crop Production Systems; Subcomponent 1A: Annual Cropping Systems; Problem Statement 1A.4: Develop Crop Production Systems that are Productive, Profitable, and Environmentally Acceptable.
5.Significant Activities that Support Special Target Populations
|Number of Non-Peer Reviewed Presentations and Proceedings||1|
|Number of Newspaper Articles and Other Presentations for Non-Science Audiences||1|
Thomson, S.J., Smith, L. 2008. Crop Dusting Using GPS. IEEE Aerospace and Electronic Systems 23(3):14-17