Dr Andrew Hewitt
Senior Research Fellow
School of Agriculture and Food Sustainability
0427 025354
Building 8117A, Gatton Campus
Researcher biography
Dr Andrew Hewitt serves under a joint appointment as a Senior Research Fellow at The University of Queensland, Australia and a Full Professor (Research) at The University of Nebraska, USA, as well as an Adjunct Professorship at Lincoln University, New Zealand. His research is focused on application optimization and the management and modeling of chemical exposure to humans and the environment from agrichemical use in row, tree and vine crops as well as migrant pest and vector control such as locusts and mosquitoes. He received BSc, MSc and PhD degrees in the UK at the Universities of Sheffield, Cranfield and London (Imperial College) before moving to the USA in 1991 to continue his research focused on pesticide drift at New Mexico State University and then for a decade as Project Manager to the Spray Drift Task Force where he helped develop the main databases and models used by pesticide regulators in the USA, Australia, Canada and New Zealand. He has worked for The University of Queensland since 2004 on diverse projects with government, industry and academic stakeholders to solve pesticide drift challenges through applied research in wind tunnels and the field, linked with modeling. In 2008, he took on a joint appointment with UQ and Lincoln Agritech/ Lincoln University in New Zealand where he successfully wrote a research grant and led a 6-year, $6M research project for the Ministry for Business, Innovation and Employment aimed at researching safer pesticide application and drift detection in diverse crops. More recently he returned to UQ and The University of Nebraska to conduct research and modeling into spray drift management including developing new drift reduction technology schemes for the USA and Australia. His ongoing research and modeling in this area with other colleagues and PhD students in both countries is supporting the risk assessment and management needs of both government and industry in several countries.
Journal Articles
Xunwei, Wang, Zhiyan, Zhou, Boqian, Chen, Jinfeng, Zhong, Xiaolong, Fan and Hewitt, Andrew (2024). Distribution uniformity improvement methods of a large discharge rate disc spreader for UAV fertilizer application. Computers and Electronics in Agriculture, 220 108928, 108928. doi: 10.1016/j.compag.2024.108928
Li, Longlong, Zhang, Ruirui, Chen, Liping, Hewitt, Andrew J., He, Xiongkui, Ding, Chenchen, Tang, Qing and Liu, Boqin (2024). Toward a remote sensing method based on commercial LiDAR sensors for the measurement of spray drift and potential drift reduction. Science of The Total Environment, 918 170819, 1-14. doi: 10.1016/j.scitotenv.2024.170819
Hewitt, Andrew J, Galea, Victor J and O'Donnell, Christopher (2023). Application technology for bioherbicides: challenges and opportunities with dry inoculum and liquid spray formulations. Pest Management Science, 80 (1), 72-80. doi: 10.1002/ps.7823
Zhang, Ruirui, Hewitt, Andrew J., Chen, Liping, Li, Longlong and Tang, Qing (2023). Challenges and opportunities of unmanned aerial vehicles as a new tool for crop pest control. Pest Management Science, 79 (11), 4123-4131. doi: 10.1002/ps.7683
Zhang, Ruirui, Hewitt, Andrew, Li, Longlong, Yuan, Huizhu, Ferguson, J. Connor and Chen, Liping (2023). Editorial: Advanced technologies of UAV application in crop pest, disease and weed control. Frontiers in Plant Science, 14 1253841, 1253841. doi: 10.3389/fpls.2023.1253841
Liu, Boqin, Li, Longlong, Zhang, Ruirui, Tang, Qing, Ding, Chenchen, Xu, Gang, Hewitt, Andrew John and Chen, Liping (2022). Analysis of the spatial and temporal distribution of a spray cloud using commercial LiDAR. Biosystems Engineering, 223, 78-96. doi: 10.1016/j.biosystemseng.2022.08.017
Tang, Qing, Chen, Liping, Zhang, Ruirui, Deng, Wei, Xu, Min, Xu, Gang, Li, Longlong and Hewitt, Andrew (2021). Effects of application height and crosswind on the crop spraying performance of unmanned helicopters. Computers and Electronics in Agriculture, 181 105961, 1-18. doi: 10.1016/j.compag.2020.105961
Li, Longlong, Zhang, Ruirui, Chen, Liping, Yi, Tongchuan, Xu, Gang, Xue, Daxuan, Tang, Qing, Zhang, Linhuan, Hewitt, Andrew John and An, Yining (2021). Development of sensor system for real-time measurement of droplet deposition of agricultural sprayers. International Journal of Agricultural and Biological Engineering, 14 (5), 19-26. doi: 10.25165/j.ijabe.20211405.5528
Tang, Qing, Zhang, Ruirui, Chen, Liping, Deng, Wei, Xu, Min, Xu, Gang, Li, Longlong and Hewitt, Andrew (2020). Numerical simulation of the downwash flow field and droplet movement from an unmanned helicopter for crop spraying. Computers and Electronics in Agriculture, 174 105468, 1-14. doi: 10.1016/j.compag.2020.105468
Zhang, Huichun, Zhou, Hongping, Zheng, Jiaqiang, Liao, Juan and Hewitt, Andrew J. (2020). Adjuvant's influence to droplet size based on forestry pests' prevention with ground and air chemical application. Linye Kexue/Scientia Silvae Sinicae, 56 (5), 118-129. doi: 10.11707/j.1001-7488.20200514
Liao, Juan, Luo, Xiwen, Wang, Pei, Zhou, Zhiyan, O’Donnell, Chris C., Zang, Ying and Hewitt, Andrew J. (2020). Analysis of the influence of different parameters on droplet characteristics and droplet size classification categories for air induction nozzle. Agronomy, 10 (2) 256, 256. doi: 10.3390/agronomy10020256
Liao, Juan, Zang, Ying, Luo, Xiwen, Zhou, Zhiyan, Zang, Yu, Wang, Pei and Hewitt, Andrew John (2020). The relations of leaf area index with the spray quality and efficacy of cotton defoliant spraying using unmanned aerial systems (UASs). Computers and Electronics in Agriculture, 169 105228, 105228. doi: 10.1016/j.compag.2020.105228
Wang, Juan, Lan, Yubin, Wen, Sheng, Hewitt, Andrew John, Yao, Weixiang and Chen, Pengchao (2020). Meteorological and flight altitude effects on deposition, penetration, and drift in pineapple aerial spraying. Asia-Pacific Journal of Chemical Engineering, 15 (1) e2382. doi: 10.1002/apj.2382
Ferguson, J. Connor, Hewitt, Andrew J., O’Donnell, Chris C. and Kruger, Greg R. (2020). Comparison of water-sensitive paper, Kromekote and Mylar collectors for droplet deposition with a visible fluorescent dye solution. Journal of Plant Protection Research, 60 (1), 98-105. doi: 10.24425/jppr.2020.132210
Liao, Juan, Hewitt, Andrew John, Wang, Pei, Luo, Xiwen, Zang, Ying, Zhou, Zhiyan, Lan, Yubin and O'Donnell, Chris (2019). Development of droplet characteristics prediction models for air induction nozzles based on wind tunnel tests. International Journal of Agricultural and Biological Engineering, 12 (6), 1-6. doi: 10.25165/j.ijabe.20191206.5014
Wen, Yao, Zhang, Ruirui, Chen, Liping, Huang, Yanbo, Yi, Tongchuan, Xu, Gang, Li, Longlong and Hewitt, Andrew John (2019). A new spray deposition pattern measurement system based on spectral analysis of a fluorescent tracer. Computers and Electronics in Agriculture, 160, 14-22. doi: 10.1016/j.compag.2019.03.008
Liao, Juan, Zang, Ying, Luo, Xiwen, Zhou, Zhiyan, Lan, Yubin, Zang, Yu, Gu, Xiuyan, Xu, Weiming and Hewitt, Andrew John (2019). Optimization of variables for maximizing efficacy and efficiency in aerial spray application to cotton using unmanned aerial systems. International Journal of Agricultural and Biological Engineering, 12 (2), 10-17. doi: 10.25165/j.ijabe.20191202.4288
Ferguson, J. Connor, Chauhan, Bhagirath S., Chechetto, Rodolfo G., Hewitt, Andrew J., Adkins, Steve W., Kruger, Greg R. and O'Donnell, Chris C. (2019). Droplet-size effects on control of Chloris spp. with six POST herbicides. Weed Technology, 33 (1), 153-158. doi: 10.1017/wet.2018.99
Zhang, Ruirui, Li, Longlong, Fu, Wang, Chen, Liping, Yi, Tongchuan, Tang, Qing and Hewitt, Andrew J. (2019). 脉宽调制变量控制喷头雾化性能及风洞环境雾滴沉积特性. Nongye Gongcheng Xuebao, 35 (3), 42-51. doi: 10.11975/j.issn.1002-6819.2019.03.006
Wang, Guobin, Lan, Yubin, Qi, Haixia, Chen, Pengchao, Hewitt, Andrew and Han, Yuxing (2019). Field evaluation of an unmanned aerial vehicle (UAV) sprayer: effect of spray volume on deposition and the control of pests and disease in wheat. Pest Management Science, 75 (6), 1546-1555. doi: 10.1002/ps.5321
Zhang, Ruirui, Zhang, Zhen, Xu, Gang, Chen, Liping and Hewitt, Andrew J. (2018). 喷雾助剂类型及浓度对喷头雾化效果影响. Nongye Gongcheng Xuebao, 34 (20), 36-43. doi: 10.11975/j.issn.1002-6819.2018.20.005
Ferguson, J. Connor, Chechetto, Rodolfo G., Adkins, Steve W., Hewitt, Andrew J., Chauhan, Bhagirath S., Kruger, Greg R. and O'Donnell, Chris C. (2018). Effect of spray droplet size on herbicide efficacy on four winter annual grasses. Crop Protection, 112, 118-124. doi: 10.1016/j.cropro.2018.05.020
Havens, Patrick L., Hillger, David E., Hewitt, Andrew J., Kruger, Greg R., Marchi-Werle, Lia and Czaczyk, Zbigniew (2018). Field Measurements of Drift of Conventional and Drift Control Formulations of 2,4-D Plus Glyphosate. Weed Technology, 32 (5), 550-556. doi: 10.1017/wet.2018.55
Connell, Robert, Post, Scott, Ledebuhr, Mark, Moorhead, Brian and Hewitt, Andrew (2018). Drift measurements for two systems of hydrogen cyanamide spraying in kiwifruit. New Zealand Plant Protection, 71, 19-24. doi: 10.30843/nzpp.2018.71.186
Post, S. L. and Hewitt, A. J. (2018). Flat-fan spray atomization model. Transactions of the ASABE, 61 (4), 1249-1256. doi: 10.13031/trans.12572
Teske, M. E., Thistle, H. W., Riley, C. M. and Hewitt, A. J. (2018). Laboratory measurements of evaporation rate of droplets at low relative wind speed. Transactions of the ASABE, 61 (3), 919-923. doi: 10.13031/trans.12743
Roten, Roy L., Post, Scott L., Werner, Armin, Safa, Majeed and Hewitt, Andrew J. (2017). Wind tunnel flux comparisons using a phase Doppler interferometer. Journal of Plant Protection Research, 57 (3), 281-287. doi: 10.1515/jppr-2017-0040
Roten, R. L., Post, S. L., Werner, A., Safa, M. and Hewitt, A. J. (2017). Phase doppler quantification of agricultural spray compared with traditional sampling materials. New Zealand Plant Protection, 70, 142-151. doi: 10.30843/nzpp.2017.70.40
Thistle, H. W., Reardon, R. C., Bonds, J. A. S., Fritz, B. L., Hoffmann, W. C., Kees, G. J., Grob, I. J., Hewitt, A. J., O'Donnell, C. C., Felton, K. D. and Onken, B. P. (2017). Aerially released spray penetration in a tall coniferous forest canopy. Transactions of the ASABE, 59 (5), 1221-1231. doi: 10.13031/trans.59.11872
Ferguson, J. Connor, Hewitt, Andrew J. and O'Donnell, Chris C. (2016). Pressure, droplet size classification, and nozzle arrangement effects on coverage and droplet number density using air-inclusion dual fan nozzles for pesticide applications. Crop Protection, 89, 231-238. doi: 10.1016/j.cropro.2016.07.032
Ferguson, J. Connor, Chechetto, Rodolfo G., O'Donnell, Chris C., Fritz, Brad K., Hoffmann, W. Clint, Coleman, Chet E., Chauhan, Bhagirath S., Adkins, Steve W., Kruger, Greg R. and Hewitt, Andrew J. (2016). Assessing a novel smartphone application – SnapCard, compared to five imaging systems to quantify droplet deposition on artificial collectors. Computers and Electronics in Agriculture, 128, 193-198. doi: 10.1016/j.compag.2016.08.022
Ferguson, J. Connor, Chechetto, Rodolfo G., O'Donnell, Chris C., Dorr, Gary J., Moore, John H., Baker, Greg J., Powis, Kevin J. and Hewitt, Andrew J. (2016). Determining the drift potential of Venturi nozzles compared with standard nozzles across three insecticide spray solutions in a wind tunnel. Pest Management Science, 72 (8), 1460-1466. doi: 10.1002/ps.4214
Wang, Ruobing, Dorr, Gary, Hewitt, Andrew and Cooper-White, Justin (2016). Impacts of polymer/surfactant interactions on spray drift. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 500, 88-97. doi: 10.1016/j.colsurfa.2016.03.056
Ferguson, J. Connor, Chechetto, Rodolfo G., Hewitt, Andrew J., Chauhan, Bhagirath S., Adkins, Steve W., Kruger, Greg R. and O'Donnell, Chris C. (2016). Assessing the deposition and canopy penetration of nozzles with different spray qualities in an oat (Avena sativa L.) canopy. Crop Protection, 81, 14-19. doi: 10.1016/j.cropro.2015.11.013
Teske, Milton E., Thistle, Harold W., Riley, Christopher M. and Hewitt, Andrew J. (2016). Initial laboratory measurements of the evaporation rate of droplets inside a spray cloud. Transactions of the ASABE, 59 (2), 487-493. doi: 10.13031/trans.59.11543
Roten, R. L., Post, S. L., Werner, A., Hewitt, A. J. and Safa, M. (2016). Volumetric validation of mass balance using a computational phase Doppler approach for disc core nozzles. Crop Protection, 79, 128-134. doi: 10.1016/j.cropro.2015.10.018
Zhang, Huichun, Dorr, Gary J. and Hewitt, Andrew J. (2015). Retention and efficacy of ultra-low volume pesticide applications on Culex quinquefasciatus (Diptera: Culicidae). Environmental Science and Pollution Research, 22 (21), 16492-16501. doi: 10.1007/s11356-015-5480-9
Ferguson, J. Connor, O'Donnell, Chris C., Chauhan, Bhagirath S., Adkins, Steve W., Kruger, Greg R., Wang, Ruobing, Urach Ferreira, Pedro H. and Hewitt, Andrew J. (2015). Determining the uniformity and consistency of droplet size across spray drift reducing nozzles in a wind tunnel. Crop Protection, 76, 1-6. doi: 10.1016/j.cropro.2015.06.008
Creech, Cody F., Henry, Ryan S., Werle, Rafael, Sandell, Lowell D., Hewitt, Andrew J. and Kruger, Greg R. (2015). Performance of postemergence herbicides applied at different carrier volume rates. Weed Technology, 29 (3), 611-624. doi: 10.1614/WT-D-14-00101.1
Nansen, Christian, Ferguson, J. Connor, Moore, John, Groves, Lloyd, Emery, Rob, Garel, Nicolas and Hewitt, Andrew (2015). Optimizing pesticide spray coverage using a novel web and smartphone tool, SnapCard. Agronomy for Sustainable Development, 35 (3), 1075-1085. doi: 10.1007/s13593-015-0309-y
Ross, John H., Hewitt, Andrew, Armitage, James, Solomon, Keith, Watkins, Deborah K. and Ginevan, Michael E. (2015). Exposure to TCDD from base perimeter application of Agent Orange in Vietnam. Science of the Total Environment, 511, 82-90. doi: 10.1016/j.scitotenv.2014.11.083
Ross, John H., Hewitt, Andrew, Armitage, James, Solomon, Keith, Watkins, Deborah K. and Ginevan, Michael E. (2015). Handler, bystander and reentry exposure to TCDD from application of Agent Orange by C-123 aircraft during the Vietnam War. Science of the Total Environment, 505, 514-525. doi: 10.1016/j.scitotenv.2014.10.005
Roten, R. L., Connell, R. J., Hewitt, A. J. and Woodward, S. J. R. (2015). Comparison of spray dose measured on leaf surfaces with spray coverage estimated from Kromekote® paper. New Zealand Plant Protection, 68, 38-43. doi: 10.30843/nzpp.2015.68.5796
Armitage, James M., Ginevan, Michael E., Hewitt, Andrew, Ross, John H., Watkins, Deborah K. and Solomon, Keith R. (2015). Environmental fate and dietary exposures of humans to TCDD as a result of the spraying of Agent Orange in upland forests of Vietnam. Science of the Total Environment, 506-507, 621-630. doi: 10.1016/j.scitotenv.2014.11.026
Craig, Ian P., Hewitt, Andrew and Terry, Howard (2014). Rotary atomiser design requirements for optimum pesticide application efficiency. Crop Protection, 66, 34-39. doi: 10.1016/j.cropro.2014.08.012
Geoghegan, Trudyanne S., Hageman, Kimberly J. and Hewitt, Andrew J. (2014). Testing flow-through air samplers for use in near-field vapour drift studies by measuring pyrimethanil in air after spraying. Environmental Sciences: Processes and Impacts, 16 (3), 422-432. doi: 10.1039/c3em00498h
Gous, S. F., Withers, T. M. and Hewitt, A. J. (2014). A new pest management research facility: Scion's large-scale precision track sprayer. New Zealand Plant Protection, 67, 267-273. doi: 10.30843/nzpp.2014.67.5724
Fritz, Bradley K., Hoffmann, W. Clint, Kruger, Greg R., Henry, Ryan S., Hewitt, Andrew and Czaczyk, Zbigniew (2014). Comparison of drop size data from ground and aerial application nozzles at three testing laboratories. Atomization and Sprays, 24 (2), 181-192. doi: 10.1615/AtomizSpr.2013009668
Roten, R.L., Ferguson, J.C. and Hewitt, A.J. (2014). Drift reducing potential of low drift nozzles with the use of spray-hoods. New Zealand Plant Protection, 67, 274-277. doi: 10.30843/nzpp.2014.67.5725
Ferguson, J. Connor, Hewitt, Andrew J., Eastin, John A., Connell, Robert J., Roten, Rory L. and Kruger, Greg R. (2014). Developing a comprehensive drift reduction technology risk assessment scheme. Journal of Plant Protection Research, 54 (1), 85-89. doi: 10.2478/jppr-2014-0013
Dorr, Gary J., Hewitt, Andrew J., Adkins, Steve W., Hanan, Jim, Zhang, Huichun and Noller, Barry (2013). A comparison of initial spray characteristics produced by agricultural nozzles. Crop Protection, 53, 109-117. doi: 10.1016/j.cropro.2013.06.017
Roten, R. L., Hewitt, A. J., Ledebuhr, M., Thistle, H., Connell, R. J., Wolf, T. M., Sankar, S. and Woodward, S. J. R. (2013). Evaluation of spray deposition in potatoes using various spray delivery systems. New Zealand Plant Protection, 66, 317-323. doi: 10.30843/nzpp.2013.66.5706
Czaczyk, Zbigniew, Kruger, Greg and Hewitt, Andrew (2012). Droplet size classification of air induction flat fan nozzles. Journal of Plant Protection Research, 52 (4), 415-420. doi: 10.2478/v10045-012-0068-6
Fritz, Bradley, K., Hoffman, W. Clint, Bagley, W. E. and Hewitt, Andrew (2011). Field scale evaluation of spray drift reduction technologies from ground and aerial application systems. Journal of ASTM International, 8 (5), 1-11. doi: 10.1520/JAI103457
Fritz, Bradley. K., Hoffmann, W. Clint, Birchfield, Norman B., Ellenberger, Jay, Kahn, Faruque, Bagley, W. E., Thornburg, Jonathan W. and Hewitt, Andrew (2010). Evaluation of spray drift using low-speed wind tunnel measurements and dispersion. Journal of ASTM International (JAI), 7 (6), 1-14. doi: 10.1520/JAI102775
Hewitt, A.J., Solomon, K.R. and Marshall, E.J.P. (2009). Spray droplet size, drift potential, and risks to nontarget organisms from aerially applied glyphosate for coca control in Colombia. Journal of Toxicology and Environmental Health, Part A, 72 (15-16), 921-929. doi: 10.1080/15287390902929667
Hewitt, A. J. (2008). Droplet size spectra classification categories in aerial application scenarios. Crop Protection, 27 (9), 1284-1288. doi: 10.1016/j.cropro.2008.03.010
Clint Hoffmann, W., Hewitt, A. J., Ross, J. B., Bagley, W. E., Martin, D. E. and Fritz, B. K. (2008). Spray adjuvant effects on droplet size spectra measured by three laser-based systems in a high-speed wind tunnel. Journal of ASTM International, 5 (6), 101233-12. doi: 10.1520/JAI101233
Dorr, Gary, Hanan, Jim, Adkins, Steve, Hewitt, Andrew, O'Donnell, Chris and Noller, Barry (2008). Spray deposition on plant surfaces: a modelling approach. Functional Plant Biology, 35 (9/10), 988-996. doi: 10.1071/FP08056
Hoffmann, Wesley Clint and Hewitt, Andrew J. (2005). Comparison of three imaging systems for water-sensitive papers. Applied Engineering in Agriculture, 21 (6), 961-964.
Teske, Milton E., Thistle, Harold W., Reardon, Richard C., Cormier, Gerry, Amirault, Peter, Davies, David C., Scott Cameron, R., Dorr, Gary, Hewitt, Andrew J., Brown, James R., LeClere, Monique Y. and Karipot, Anandakumar (2005). Predicted deposition variability due to fluctuations in release height and drop size distribution. Journal of ASTM International, 2 (4), 283-293. doi: 10.1520/JAI12164
Teske, M. E., Thistle, H. W., Hewitt, A. J., Kirk, I. W., Dexter, R. W. and Ghent, J. H. (2005). Rotary atomizer drop size distribution database. Transactions of the ASABE, 48 (3), 917-921. doi: 10.13031/2013.18496
Teske, Milton E., Kaufman, Andrew E., Thistle, Harold W., Hewitt, Andrew J. and Valcore, David L. (2003). Droplet evaporation corrections for aerial spray drift modeling I: Theoretical considerations. Atomization and Sprays, 13 (2-3), 243-250. doi: 10.1615/atomizspr.v13.i23.50
Teske, Milton E., Thistle, Harold W., Hewitt, Andrew J. and Kirk, I. W. (2002). Conversion of droplet size distributions from PMS optical array probe to Malvern laser diffraction. Atomization and Sprays, 12 (1-3), 267-281. doi: 10.1615/atomizspr.v12.i123.140
Hewitt, Andrew J., Johnson, David R., Fish, John D., Hermansky, Clarence G. and Valcore, David L. (2002). Development of the spray drift task force database for aerial applications. Environmental Toxicology and Chemistry, 21 (3), 648-658. doi: 10.1002/etc.5620210326
Hewitt, Andrew J., Valcore, D. L. and Barry, T. (2001). Analyses of equipment, meteorology and other factors affecting drift from applications of sprays by ground rig sprayers. ASTM Special Technical Publication (1400), 44-56. doi: 10.1520/stp10433s
Hewitt, A. J. (2001). Developments in international harmonization of pesticide drift management. Phytoparasitica, 29 (2), 93-96. doi: 10.1007/BF02983952
Hewitt, A. J. (2000). Spray drift: Impact of requirements to protect the environment. Crop Protection, 19 (8-10), 623-627. doi: 10.1016/S0261-2194(00)00082-X
Hewitt, Andrew J., Stern, A. J., Bagley, W. E. and Dexter, R. (1999). The formation of a new ASTM E35.22 task group to address drift management adjuvants. ASTM Special Technical Publication (1373), 135-148.
Sanderson, R., Hewitt, A. J., Huddlestor, E. W. and Ross, J. B. (1997). Relative drift potential and droplet size spectra of aerially applied propanil formulations. Crop Protection, 16 (8), 717-721. doi: 10.1016/S0261-2194(97)00064-1
Hewitt, Andrew (1997). Droplet size and agricultural spraying, Part I: Atomization, spray transport, deposition, drift, and droplet size measurement techniques. Atomization and Sprays, 7 (3), 235-244. doi: 10.1615/AtomizSpr.v7.i3.10
Hewitt, A. J., Sanderson, R., Huddleston, E. W. and Robinson, A. G. (1994). Comparison of the droplet size spectra produced by rotary atomizers and hydraulic nozzles under simulated aerial application conditions. Journal of Environmental Science and Health, Part B, 29 (4), 647-660. doi: 10.1080/03601239409372898
Sanderson, R., Hewitt, A. J., Huddleston, E. W. and Ross, J. B. (1994). Polymer and invert emulsifying oil effects upon droplet size spectra of sprays. Journal of Environmental Science and Health, Part B, 29 (4), 815-829. doi: 10.1080/03601239409372905
Hewitt, A. J. and Meganasa, T. (1993). Droplet distribution densities of a pyrethroid insecticide within grass and maize canopies for the control of Spodoptera exempta larvae. Crop Protection, 12 (1), 59-62. doi: 10.1016/0261-2194(93)90021-A
Hewitt, A.J (1993). Droplet size spectra produced by air-assisted atomizers. Journal of Aerosol Science, 24 (2), 155-162. doi: 10.1016/0021-8502(93)90055-E
Hewitt, A. J. (1992). Droplet size spectra produced by the X15 stacked spinning-disc atomizer of the Ulvamast Mark II sprayer. Crop Protection, 11 (3), 221-224. doi: 10.1016/0261-2194(92)90040-C
Conference Papers
Creech, Cody F., Henry, Ryan S., Hewitt, Andrew J. and Kruger, Greg R. (2018). Herbicide spray penetration into corn and soybean canopies using air-induction nozzles and a drift control adjuvant. Cambridge, United Kingdom: Cambridge University Press. doi: 10.1017/wet.2017.84
Costa, Fernanda, Forster, W. Alison, Favaro, Cintia, Golfetti da Silva, Vanessa R. and Hewitt, Andrew (2018). Is Retention the Old-New Problem in a Drift-Control Era?. 38th Symposium on Pesticide Formulation and Delivery Systems: Innovative Application, Formulation, and Adjuvant Technologies, New Orleans LA United States, 10-12 October 2017. West Conshohocken, PA United States: A S T M International. doi: 10.1520/STP167020770213
Roten, Rory, Post, Scott and Hewitt, Andrew (2016). Phase doppler flux comparisons. 2016 ASABE Annual International Meeting, Orlando, Florida, United States, 17-20 July 2016. St Joseph, MI, United States: American Society of Agricultural and Biological Engineers. doi: 10.13031/aim.20162461508
Roten, R. L., Ferguson, J. C., Connell, R. J., Dorr, G. J. and Hewitt, A. J. (2015). Preliminary investigation of Phase Doppler derived flux measurements in a wind tunnel for the sampling of orchard spray drift. 13th Workshop on Spray Application in Fruit Growing, Lindau Germany, Jul 15-18, 2015. Germany: Julius Kühn-Institut. doi: 10.5073/jka.2015.448.000
Hewitt, Andrew (2014). Evaluation of models for ground-based pesticide application systems. 248th National Meeting of the American Chemical Society (ACS), San Francisco CA, United States, 10-14 August 2014. Washington, DC United States: American Chemical Society.
Wang, Ruobing, Door, Gary, Hewitt, Andrew and Cooper-White, Justin (2014). How conformation change in polymer-surfactant system influence spray performance through flat fan nozzle. 248th National Meeting of the American Chemical Society (ACS), San Francisco CA, United States, 10-14 August 2014. Washington, DC United States: American Chemical Society.
Kateley, Stephen, Hewitt, Andrew, Brady, Mick and Goddard, Richard (2014). Wireless mobile device for counting and measuring spray droplets. 248th National Meeting of the American Chemical Society (ACS), San Francisco CA, United States, 10-14 August 2014. Washington, DC United States: American Chemical Society.
Wang, Ruobing, Dorr, Gary, Hewitt, Andrew and Cooper-White, Justin (2014). Effect of interaction in polymer-surfactant systems on spray drift. 248th National Meeting of the American Chemical Society (ACS), San Francisco CA, United States, 10-14 August 2014. Washington, DC United States: American Chemical Society.
Hewitt, Andrew (2013). Ground spray drift modeling for pesticide application. 246th National Meeting of the American Chemical Society (ACS), Indianapolis, IN United States, 8 - 12 September 2013. Washington, DC United States: American Chemical Society.
Fritz, Bradley K., Hoffmann, W. Clint, Bagley, W. E. and Hewitt, Andrew (2011). Field scale evaluation of spray drift reduction technologies from ground and aerial application systems. ASTM International. doi: 10.1520/stp153720120013
Fritz, Bradley K., Hoffmann, W. Clint, Birchfield, Norman B., Ellenberger, Jay, Khan, Faruque, Bagley, W. E., Thornburg, Jonathan W. and Hewitt, Andrew (2011). Evaluation of spray drift using low-speed wind tunnel measurements and dispersion modeling. ASTM International. doi: 10.1520/stp152720120018
Hewitt, Andrew J. (2010). Drift reduction technologies in Australia and New Zealand. 239th ACS National Meeting & Exposition, San Francisco CA, United States, 21-25 March 2010.
Hewitt, A. J. (2010). Tracer and collector systems for field deposition research. Aspects of Applied Biology 99, Cambridge, U. K., 5-7 January 2010. Warwick, U.K.: Association of Applied Biologists.
Ice. W., Thistle, H., Karsky, R. and Hewitt, A. (2010). Attenuation of aerially applied spray within a riparian management area. SAF 2010 National Convention, Albuquerue, NM, U.S.A., 27-31 October 2010.
Hoffmann, W. C., Fritz, B., Hewitt, A. J. and Bagley, W. (2010). Effects of air speed and liquid temperature on atomization of sprays under ground application conditions. 31st Symposium on Pesticide Formulations and Delivery Systems: Innovative Green Chemistries for the 21st Century, San Antonio, Texas, United States, 12-14 October 2010. West Conshohocken, PA, United States: ASTM International.
Hewitt, A. J., Hoffman, W. C., Miller, P., Fritz, B., Thistle, H., Teske, M., Dorr, G., O'Donnell, C., Bagley, W., Giles, D., Czazykz, Z., Connell, R., Birchfield, N. and Martin, D. (2010). Development of a drift reduction technology deposition model based on spray characteristics from wind tunnel and field sampling. 31st Symposium on Pesticide Formulations and Delivery Systems: Innovative Green Chemistries for the 21st Century, San Antonio, Texas, USA, 12-14 October 2010.
Hewitt, Andrew (2010). International standards for drift reduction technology studies. 2010 Joint Annual Meeting of the Society for Range Management (SRM) and Weed Society of America (WSSA), Denver, Colorado, USA, 7 - 11 February 2010.
Connell, R. J., Woodward, S. J. R., Zabkiewicz, J. A. and Hewitt, A. J. (2010). Shelterbelt interception of agrichemicals: Model and field results. 2010 Meeting of the Association of Applied Biologists: International Advances in Pesticide Application, Cambridge, United Kingdom, 5-7 January 2010. Wellesbourne, Warwick, United Kingdom: Association of Applied Biologists.
Hewitt, Andrew J., Forster, Alison, Teske, Milton E. and Thistle, Harold W. (2010). AGDISP Model Developments in USA, Australia and New Zealand. ForestTECH 2010 - Technologies to Improve Forest Planning, Albury, New South Wales, Australia, 22 - 24 November 2010.
Hoffmann, W. C., Fritz, B. and Hewitt, A. (2010). Development and testing of an aerial application standardized spray system. 31st Symposium on Pesticide Formulations and Delivery Systems: Innovative Green Chemistries for the 21st Century, San Antonio, Texas, United States, 12-14 October 2010.
Fritz, B., Hoffmann, W. C., Birchfield, N., Ellenberger, J., Kosusko, M., Khan, F. and Hewitt, A. (2010). Field scale evaluation of spray drift reduction technologies from ground and aerial application systems. 31st Symposium on Pesticide Formulations and Delivery Systems: Innovative Green Chemistries for the 21st Century, San Antonio, Texas, USA, October 12-14 2010.
Connell, R. J., Hewitt, A., Wolf, T. and Miller, P. C.H. (2009). WTDISP - Adapting a Lagrangian ground sprayer model using wind tunnel data. Modelling and Simulation Society of Australia and New Zealand Inc. (MSSANZ).
Thistle, H. W., Ice, G. G., Karsky, R.L., Hewitt, A.J. and Dorr, G. (2009). Deposition of aerially applied spray to a stream within a vegetative barrier. 2007 ASABE Annual International Meeting, Minneapolis, MN United States, 2007. Joseph, MI United States: American Society of Agricultural and Biological Engineers. doi: 10.13031/2013.29128
Hewitt, Andrew J. (2008). Spray optimization through application and liquid physical property variables-I. doi: 10.1007/s10669-007-9044-5
Clint Hoffmann, W., Hewitt, A. J., Ross, J. B., Bagley, W. E., Martin, D. E. and Fritz, B. K. (2008). Spray adjuvant effects on droplet size spectra measured by three laser-based systems in a high-speed wind tunnel. Pesticide Formulations and Delivery Systems: Reassessing Pesticide Technologies, Dallas, TX, 17 - 20 October 2005. West Conshohocken, PA United States: ASTM International.
Dorr, S., Adkins, S., Hanan, J., O'Donnell, C., Hewitt, A. and Noller, B. (2007). Optimisation of herbicide deposition and retention using computer modeling validated through wind tunnel studies. 21st Asian Pacific Weed Science Society (APWSS) Conference, Colombo, Sri Lanka, 2-6 October 2007. Colombo, Sri Lanka: University of Peradeniya and Chemical Industries.
Dorr, G., Noller, B. N., Woods, N., Hewitt, A. J., Hanan, J. S., Adkins, S. W. and Ricci, P. F. (2007). Development of a Decision-Making Tool to Minimize Environmental and Public Health Risk of Pesticide Application. International Chemical Congress of Pacific Basin Societies (PACIFICHEM 2005), Honolulu, HI, 15-20 Dec 2005. Washington, D.C.: American Chemical Society. doi: 10.1021/bk-2007-0966.ch004
Dorr, Gary J., Hanan, Jim, Hewitt, Andrew J., Adkins, Steve and Noller, Barry N. (2007). Modeling the Interaction of Plant Architecture and Spray Techniques. 2007 ASABE Annual International Meeting, Minneapolis, Minnesota, 17-20 June, 2007. St. Joseph, Michigan: American Society of Agricultural and Biological Engineers.
Dorr, G. J., Noller, B N, Hewitt, A J, Hanan, J S and Adkins, S W (2006). A decision-making tool to minimise environmental and public health risk of pesticide application. 6th Annual Health and Medical Research conference of Queensland, Hilton Hotel, Brisbane, 23-24 November 2006. Brisbane, QLD: Queensland Government.
Dorr, G. J., Noller, B., Hanan, J., Adkins, Stephen W., Woods, N., Hewitt, A. and Ricci, P. (2005). Development of a decision-making tool to minimise environmental and public health risk of pesticide application. 2005 International Chemical Congress of Pacific Basin, Honolulu, Hawaii, USA, 15-20 December, 2005.
Noller, B. N., Hewitt, A. J., Woods, N., Dorr, G. J. and Kleinmeulman, P. A. (2005). Applicability of a controlled environment facililty for Aerosol Toxicological Exposure Assessments. Downunder Intern. Conf. on the Removal or Destruction of Highly Toxic Chemical & Biol. Contamination, Melbourne, Vic, 13-16 February 2005. Canberra, Australia: Department of Defense.
Hewitt, A. J., Woods, N., O'Donnell, C. C., Dorr, G. J., Gardner, A. D. and Noller, B. N. (2005). Modelling Chemical Exposure to Aquatic Ecosystems. Australian Coral Reef Society Conference, Heron Island, 20-22 August 2005. Gatton: Centre for Pesticide Application and Safety.
Teske, Milton E., Thistle, Harold W., Reardon, Richard C., Cormier, Gerry, Amirault, Peter, Davies, David C., Cameron, R. S., Dorr, Gary, Hewitt, Andrew J., Brown, James R., Le Clerc, Monique Y. and Karipot, Anandakumar (2005). Predicted deposition variability due to fluctuatioins in release height and drop size distribution. ASTM International.
Dorr, G. J., Woods, N., Hewitt, A. J., Hanan, J. S., Kleinmeulman, P. A. and Adkins, S. W. (2004). Modelling wind tunnel drift measurements. Intern'l Conf on Pesticide Application for Drift Management, Hawaii/Hilton Waikoloa Village, 27-29 October 2004. Pullman, Washington: Washington State University Extension.
Hoffmann, W. C. and Hewitt, A. J. (2004). Comparison of three imaging systems for water-sensitive papers. ASAE Annual International Meeting 2004, Ottawa, Canada, 1-4 August 2004. St Joseph, MI, USA: ASAE.
Teske, Milton E., Hewitt, Andrew J. and Valcore, David L. (2004). Suggested revisions to ASAE standard S572 Aug99. ASAE Annual International Meeting 2004, Ottawa, Canada, 1-4 August 2004. St Joseph, MI, USA: ASAE.
Boyd, A., Hewitt, A. J., Dorr, G. J., Kleinmeulmann, P. and Noller, B. N. (2004). Wind tunnels, lasers and mosquitoes - Applications for control studies. 4th Annual Queensland Health and Medical Scientific Meeting, Brisbane, 30 Nov - 1 Dec 2004. Brisbane: Queensland Health.
Kleinmeulman, P. A., Dorr, G. J., Woods, N., Hewitt, A. J., Noller, B. N., Hanan, J. S. and Adkins, S. W. (2004). Comparing droplet size and velocity of different hydraulic nozzle spray plumes. Intern'l Conf on Pesticide Application for Drift Management, Hawaii/Hilton Waikoloa Village, 27-29 October 2004. Pullman, Washington: Washington State Unviersity Extension.
Teske, Milton E., Hewitt, Andrew J. and Ice, George G. (2003). Characterizing granular material in aerial application. American Society for Testing and Materials.
Hewitt, A.J., Zany, W., Dorr, G. J. and Woods, N. (2001). Droplet size spectra from rotary atomizers and hydraulic nozzles in mosquito control. Dearborn, MI, USA, May 2001. Irvine, CA, USA: ILASS Americas (Institute of Liquid Atomization and Spray Systems, North & South America).
Teske, Milton E., Hewitt, Andrew J. and Mickle, Robert E. (2001). The measurement of droplet size distributions from rotary atomizers. American Society for Testing and Materials. doi: 10.1520/stp10729s
Maber, J., Dewar, P., Praat, J. P. and Hewitt, A. J. (2001). Real time spray drift prediction. International Society for Horticultural Science. doi: 10.17660/ActaHortic.2001.566.64
Miller, Paul C. H., Hewitt, A. J. and Bagley, W. E. (2001). Adjuvant effects on spray characteristics and drift potential. American Society for Testing and Materials. doi: 10.1520/stp10727s
Apodaca, M. A., Sanderson, R., Huddleston, E. W., Clason, D. L., Hewitt, A. J., Ledson, T. M., Ross, J. B. and Ortiz, M. (1996). Drift control polymers and formulation type affect volumetric droplet size spectra of propanil sprays. Taylor and Francis Inc.. doi: 10.1080/03601239609373041