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Team Leader

Tobin Northfield

Tobin Northfield

Tobin is an Assistant Professor in the WSU Entomology Department, and is at the WSU Tree Fruit Research and Extension Center in Wenatchee Washington. Prior to joining WSU he was a Lecturer and Senior Lecturer at James Cook University in Cairns Australia. While he is no longer recruiting new students at JCU, he continues to advise students he was supervising there. His publications are available at his Google Scholar profile. Tobin can be contacted at

Research Technician

Tawnee Melton

Tawnee Melton

Tawnee is a research technician in the laboratory working on a range of projects, such as improving management of little cherry disease, pear psylla, and codling moth. She has extensive experience researching entomology and tree fruit integrated pest management at the Wenatchee Tree Fruit Research and Extension Center. Tawnee can be contacted at:


Jones, VP, DR Horton, NJ Mills, TR Unruh, CC Baker, TD Melton, E Milickzy, SA Steffan, PW Shearer, KG Amarasekare. 2016. Evaluating plant volatiles for monitoring natural enemies in apple, pear and walnut orchards. Biological Control, 102: 53-65.

NJ Mills, VP Jones, CC Baker, TD Melton, SA Steffan, TR Unruh, DR Horton, PW Shearer, KG Amarasekare, E Milickzy. 2016. Using plant volatile traps to estimate the diversity of natural enemy communities in orchard ecosystems. Biological Control, 102: 66-76.

Jones, VP, DR Horton, NJ Mills, TR Unruh, E Miliczky, PW Shearer, KG Amarasekare, CC Baker, TD Melton. 2016. Using plant volatile traps to develop phenology models for natural enemies: An example using Chrysopa nigricornis (Burmeister) (Neuroptera: Chrysopidae). Biological Control, 102: 77-84.

Jones, VP, TD Melton, CC Baker. 2011. Optimizing immunomarking systems and development of a new marking system based on wheat. Journal of Insect Science, 11: 87.

Postdoctoral Researchers

Dylan Beal

Dylan Beal

Dylan Beal is a postdoctoral researcher working on novel, environmentally sustainable management of spotted wing drosophila in cherries and blueberries, and is co-advised by Betsy Beers and Tobin. He conducted his PhD at UC Berkeley on spittlebugs and Pierce’s Disease, and a MS degree at Universita degli Studi di Torino on Flavescence Dorée phytoplasma and its vector Scaphoideus titanus. Dylan can be contacted at

Publications (See Google Scholar profile for up to date list):

Beal, DJ, AG Adams, ML Cooper, LG Varela, RJ Smith, CR Kron, RPP Almeida and MP Daugherty. In press. Assessment of nymphal ecology and adult Xylella fastidiosa transmission biology of Aphrophora nr. permutata (Hemiptera: Aphrophoridae) in California vineyards. Environ Entomol.

Beal, DJ, M Cooper, MP Daugherty, AH Purcell, RPP Almeida. 2021. Seasonal abundance and infectivity of Philaenus spumarius (Hemiptera: Aphrophoridae), a vector of Xylella fastidiosa in California vineyards. Environ Entomol. 50: 467-476.

Zeilinger, AR, CM Wallis, D Beal, A Sicard, MA Walker, RPP Almeida. 2021. Plant defense against a pathogen drives nonlinear transmission dynamics through both vector preference and acquisition. Ecosphere 12, e0237545.

Wallis, CM, AR Zeilinger, A Sicard, DJ Beal, MA Walker, RPP Almeida. 2020. Impact of phenolic compounds on progression of Xylella fastidiosa infections in susceptible and PdR1-locus containing resistant grapevines. PLoS One. 15, e02374545.

Ripamonti, M, M Pegoraro, M Rossi, N Bodino, D Beal, L Panero, C Marzachì, D Bosco. 2020. Prevalence of Flavescence dorée phytoplasma-infected Scaphoideus titanus in different vineyard agroecosystems in Northwestern Italy. Insects. 11:301.

Adrian Marshall

Adrian Marshall holding a snake

Adrian is a postdoctoral research evaluating environmental friendly controls (kaolin clay and reflective ground cover) on little cherry disease and the leafhoppers that vector the X disease phytoplasma. He conducted his PhD at WSU with Betsy Beers on cultural control of apple pests. Adrian can be contacted at:

Publications (See Google Scholar profile for most up-to-date list):

Marshall, AT, EH Beers. 2021. Efficacy and nontarget effects of net exclusion enclosures on apple pest management. J Economic Entomology,

Adesanya, A, B Lee, A Cohen, A Hayes, J Hepler, and A. Marshall. 2019. Habitat loss via land-use change. American Entomologist. 65: 50-60.

Beers, EH, AT Marshall, J Hepler, and JM Milnes. 2019. Prospects for integrated pest management of brown marmorated stink bug in Washington tree fruits. Outlooks Pest Manag. 30. 25-32.

Marshall, AT and EH Beers. 2018. Chemical control of woolly apple aphids. Arthropod Management Tests. 43(1).

Beers, EH and AT Marshall. 2017. Brown marmorated stink bug. Orchard Pest Management Online.

Whaley, DK, A Marshall, CK Yoon, and MA Peterson. (2017). Parabacillus hesperus Hebard, 1934 (Phasmida: Heteronemiidae): new state records for Washington and Idaho and an assessment of its distribution in the Pacific Northwest (USA). The Pan-Pacific Entomologist 93: 22-28.

Graduate Students

Abby Clarke

Abigail Clarke

Abby is a MS student in the department of Entomology at WSU. Her research focuses on host use and life history by the leafhoppers that vector X disease. Prior to starting at WSU she received her BS degree at University of Delaware. Abby can be contacted at

Cesar Reyes Corral

Cesar Reyes Corral holding plants

Cesar is applying a combination of molecular and ecological techniques to better understand the little cherry disease (X disease phytoplasma and leafhopper vectors) system to improve management. He earned an MS degree from University of Idaho where he combined molecular techniques and field research to describe the role of non-host plants as reservoirs for zebra chip disease in potatoes. Cesar can be contacted at

Publications (See Google Scholar profile for up to date list):

Reyes Corral CA, WR Cooper, AV Karasev, C Delgado-Luna, SR Sanchez-Pena. In press. “Candidatus Liberibacter solanacearum” infection of commercial tomatillo, Physalis ixocarpa Brot. (Solanales: Solanaceae) in Saltillo, Mexico. Plant Disease.

Dahan, J, EJ Wenninger, M Thornton, CA Reyes Corral, N Olsen, AV Karasev. In press. Haplotyping the Potato Psyllid (Hemiptera: Triozidae) and the Associated Pathogenic Bacterium ‘Candidatus Liberibacter solanacearum’ in Non-crop Alternative Hosts in Southern Idaho. Environmental Entomology.

Beck, K, CA Reyes Corral, M Rodriguez-Rodriguez, C May, R Barnett, M Thornton, AA Bates, J W Woodhall, BK Schroeder. 2021. First report of Fusarium proliferatum causing necrotic leaf lesions and bulb rot on storage onion (Allium cepa) in southwestern Idaho. Plant Disease, 105: 494-494.

Reyes Corral, CA, WR Cooper, DR Horton, AV Karasev. 2020. Susceptibility of Physalis longifolia (Solanales: Solanaceae) to Bactericera cockerelli (Hemiptera Triozidae) and ‘Candidatus Liberibacter solanacearum.’ Journal of Economic Entomology. 113: 2595-2603.

Ed Evans

Ed Evans

Ed is conducting his PhD at JCU and his primary adviser is Dave Wilson. He is working to identify the factors driving venom traits in scorpions. Ed can be contacted at at

Publications (see Google Scholar profile for up to date list):

Giribaldi, J., Y Haufe, ERJ Evans, DT Wilson, NL Daly, C Enjalbal, A Nicke, S Dutertre. 2021. Synthesis, structural and pharmacological characterizations of CIC, a novel alpha-conotoxin with an extended N-terminal tail. Marine Drugs, 19:141.

Evans, ERJ, L McIntyre, TD Northfield, NL Daly, DT Wilson. 2020. Small molecules in the venom of the scorpion Hormurus waigiensis. Biomedicines, 8: 259.

Giribaldi, J., Y Haufe, ERJ Evans, M Amar, A Durner, C Schmidt, A Faucherre, HMO Maati, C Enjalbal, J Molgo, D Servent, DT Wilson, NL Daly, A Nicke, S Dutertre. 2020. J Medicinal Chemistry, 63: 12686-12692.

Evans, ERJ, TD Northfield, NL Daly, DT Wilson. 2019. Venom costs and optimisation in scorpions. Frontiers in Ecology and Evolution, 7: 196

Samantha Forbes

Samantha Forbes

Samantha is a PhD student at James Cook University. Her work focuses on pollinator and plant biology in an effort to improve food production in the tropics. She is also advised by Lucas Cernusak at JCU, and her research is funded by Mars Inc. Prior to starting her PhD she conducted her MSc research at JCU, and identified methods of simultaneously improving pollination and predator abundance in cacao farms through better habitat management. Samantha has conducted many media interviews about her research, including on Science Friday. Samantha works for Mars as a Farm System Diversification Manager while she finishes her PhD. Samantha can be contacted at


Forbes, SJ, L Cernusak, TD Northfield, RM Gleadow, A Cheesman. 2020. Elevated temperature and carbon dioxide alter resource allocation to growth, storage and defence in cassava (Manihot esculenta). Environmental and Experimental Botany. 173: 103997.

Forbes, SJ, G Mustiga, A Romero, TD Northfield, S Lambert, JC Motamayor. 2019. Supplemental and synchronized pollination may increase yield in cacao. HortScience, 54: 1718-1727.

Forbes, SJ, TD Northfield 2017. Increased pollinator habitat enhances cacao fruit set and predator conservation. Ecological Applications, 27: 887-899

Forbes, SJ, TD Northfield. 2017. Oecophylla smaragdina ants provide pest control in Australian cocoa. Biotropica, 49: 328-336.

Aldo Hanel

Aldo is a PhD student at WSU co-advised by Tobin Northfield, with Rebecca Schmidt-Jeffris at USDA in Wapato, and Louis Nottingham at WSU. Aldo conducted his MS research at Federal University of Vicosa in Brazil on mite ecology and biological control. For his PhD he will working on the role of earwigs in tree fruit systems. Aldo can be contacted at:

Publications (See Google Scholar profile for most up-to-date publications):

Oliveira NC, Suzukawa AK, Pereira CB, Santos HV, Hanel A., Albuquerque FA, Scapim CA. 2018. Popcorn
genotypes resistance to fall armyworm. Ciência Rural, 48.

Souza IJ, Neto AMO, Hanel, A, Filho PJF, Guerreiro JC, Oliveira NC 2018. Chemical control of stink bug on maize. Journal of Agronomical Sciences, 7: 177-183.

Oliveira MC, Meert L, Hanel A, Ramos ML, Krenski A (2018). Foliar application of Nitrogen, Sulfur,
Molybdene and Nickel and its effect on agronomic characteristics and protein content of soybean. Journal of
Agronomical Sciences, 7: 79-86.


Amy McGuire

Amy McGuire

Amy is conducting her PhD at JCU on the use of entomopathogenic fungi to control fruit flies. She previously conducted her Honours research at JCU on evaluating soil characteristics that promote entomopathogenic fungi in banana farms as part of her efforts to identify a fungal pathogen to control thrips. She also uses theoretical models to evaluate the effects of environmental conditions on diversification of host-parasite communities. Her Honours research was in collaboration with Pacific Eco Bananas, and has been covered in several media outlets, including ABC Australia’s Landline. Amy can be contacted at:


McGuire, AV, TD Northfield. 2021. Identification and evaluation of endemic Metarhizium strains for biological control of banana rust thrips. Biological Control, 162: 104712.

McGuire, AV, TD Northfield. 2020. Tropical occurrence and agricultural importance of Beauveria bassiana and Metarhizium anisopliae. Frontiers in Sustainable Food Systems, 4:6.

Ryan Orr

Ryan Orr

Ryan is conducting his PhD research at JCU, and is primarily advised by Paul Nelson. He is identifying the soil characteristics and management strategies that alter prevalence of Panama Disease, a fungal pathogen that damages bananas worldwide. Ryan currently works at the Queensland Department of Agriculture and Fisheries while he finishes his PhD. Ryan can be contacted at

Publications (See Google Scholar profile for most up-to-date list):

Orr, R, PN Nelson. 2021. Eucalyptus cloeziana mulch suppresses Fusarium wilt of banana. Crop Protection, 105694.

Orr, R., A Pattison, T Northfield, PN Nelson. 2021. Iron chelates have little to no effect on the severity of Fusarium wilt of bananas in soils of the wet tropics. J Plant Pathology, 103: 595-604.

Orr, R., RK Hocking, A Pattison, PN Nelson. 2020. Extraction metals from mildly acidic tropical soils: Interactions between chelating ligand, pH and soil type. Chemosphere, 248: 126060.

Oliver, DP, Y Li, R Orr, P Nelson, M Barnes, MJ McLaughlin, RS Kookana. 2019. The role of surface charge and pH changes in tropical soils on sorption behaviour of per- and polyfluoroalkyl substances (PFASs). Science of the Total Environment, 673: 197-206.

Orr, R. A Pattison, D East, N Warman, W O’Neill, E Czislowski, PN Nelson. 2019. Image-based quantification of Fusarium wilt severity in banana. Australasian Plant Disease Notes, 14: 14.

A Bowen, R Orr, AV McBeath, A Pattison, PN Nelson. 2019. Suppresiveness or conduciveness to Fusarium wilt of bananas differs between key Australian soils. Soil Research, 57: 158-165.

Orr, R, and PN Nelson. 2018. Impacts of soil abiotic attributes of Fusarium wilt, focusing on bananas. Applied Soil Ecology, 262: 1-10.

Orr, R, A McBeath, AV Dieleman, MI Bird, PN Nelson. 2017. Estimating organic carbon content of soil in Papua New Guinea using infrared spectroscopy. Soil Research, 55: 735-742.

Jeremy Roberts

Jeremy with fish specimen

Jeremy is a MS student at WSU combining theoretical and empirical approaches to better understand codling moth ecology and management. He conducted his bachelor’s degree at Cal Poly San Luis Obispo in computer science. Jeremy can be contacted at

Molly Sayles

Molly Sayles in forest

Molly Sayles is conducting her PhD on pear psylla ecology and management advised by Louis Nottingham, and co-advised by Tobin. She earned a BS at Oberlin College and has experience researching emerald ash borer in Ohio, fungus beetles in Virginia, and soil science in Peru. Molly can be contacted at

Peter Smytheman

Peter Smytheman in front of light trap

Peter Smytheman is conducting his MS on the natural enemies of leafhoppers that vector X-disease in cherry orchards. He is also working in Betsy Beers’ lab on spotted wing drosophila and brown marmorated stink bug. He has a background in commercial production of biological control agents and is an avid insect collector. Peter can be contacted at

Micaiah Northfield

Micaiah Northfield

Micaiah is the youngest member of the lab group. He has pioneered an innovative approach of demonstrating how niche partitioning works in communities of biological control agents through an analogy of construction equipment. He is shown here writing R code for a simulation model showing how efficiency improves with increases in the diversity of construction equipment when a variety of tasks must be completed. His work currently focuses on a combination of simulation and physical models, but he hopes to move on to real systems in the future.

Hall of Fame (lab alumni)

Eli Bloom

Eli completed his PhD at WSU, and was advised by Dave Crowder. He came to JCU on an NSF fellowship to develop his theoretical skills and develop novel analyses of his pollinator data sets. His research focuses on the stability and diversity of pollinator communities in diversified farming systems. He is now a postdoctoral researcher with Zsofia Szendrei at Michigan State University.

Resulting publications:

Milner, JRD, EH Bloom, DW Crowder, TD Northfield. In press. Plant evolution can mediate negative effects from honey bees on wild pollinators. Ecology and Evolution.

Bloom, E, TD Northfield, DW Crowder. 2019. A novel application of the Price equation reveals that landscape diversity promotes the response of bees to regionally rare plant species. Ecology Letters, 22: 2103-2110.


David Clarke

David Clarke

David conducted his Honour’s research at JCU focused on the factors driving invertebrate diversity in seagrass meadows, and was coadvised by Paul York and Michael Rasheed from TropWATER. He is currently a PhD student working with Melodie McGeoch at Monash University in Melbourne, Australia.

Resulting publications:

Carke, DA, PH York, MA Rasheed, TD Northfield. 2017. Identifying areas in need of tropical research. Trends in Ecology and Evolution. 32: 628.

Clarke, DA, PH York, MA Rasheed, TD Northfield. 2017. Does biodiversity-ecosystem function literature neglect tropical ecosystems? Trends in Ecology and Evolution, 32: 320-323.

Jade Ferguson

Jade Ferguson

Jade conducted her Honours research at JCU, and was primarily advised by Lori Lach. Through experiments and observational studies she documented the effects of a honey bee parasite, Nosema ceranae, on honey bee foraging preferences and the effects of pollen quality on the likelihood that honey bees can survive the parasite.

Resulting publication:

Ferguson, JA, TD Northfield, L Lach. 2018. Honey bee (Apis Mellifera) pollen foraging reflects benefits dependent on individual infection status. Microbial Ecology, 76: 482-491.

Alex Gangur

Alex conducted his Honours research at JCU. Through his experiments on scorpsion, he identified for the first time that predator exposure can induce changes in venom composition, and used theoretical models to describe the effects of top-down and bottom-up effects on venom evolution in venomous mesopredators. Alex’s research was discussed in a number of media outlets. He is now a PhD student with Dustin Marshall at Monash University in Melbourne, Australia.

Resulting publications:

Gangur, AN, JE Seymour, MJ Lidell, D Wilson, MJ Smout, TD Northfield. 2018. When is overkill optimal? Tritrophic interactions reveal new insights into venom evolution. Theoretical Ecology, 11: 141-149

Gangur, AN, MJ Smout, MJ Lidell, JE Seymour, D Wilson, TD Northfield. 2017. Changes in predator exposure, but not diet induce phenotypic plasticity in scorpion venom. Proceedings of the Royal Society: B, 284:  20171364.


Desiree Gowell

Desiree Gowell

Desiree conducted her MSc special project at JCU on the spatio-temporal distributions of pests and their natural enemies in cacao farms. She is now a GIS analyst at the Wet Tropics Management Authority.

James Milner

As an undergraduate at JCU, James conducted used ecoevolutionary models to evaluate the potential effects of honey bees on native plant-pollinator interactions in collaboration with Tobin, Eli Bloom, and Dave Crowder (Eli’s advisor). For his Honours research he used mechanistic models to evaluate the effects of environmental conditions on tropical rainforest communities, and competition models to evaluate the effects of indirect interactions on community stability.

Resulting publication:

Milner, JRD, EH Bloom, DW Crowder, TD Northfield. 2020. Plant evolution can mediate negative effects from honey bees on wild pollinators. Ecology and Evolution, 10: 4407-4418

Alfonso Moreno

Alfonso Moreno

Alfonso conducted his Honours research at JCU and was primarily advised by Sean Connolly. His research focused on community dynamics models to evaluate the processes driving patterns of species abundance generally found in ecological communities. Alfonso is now a PhD student with Sean Connolly at JCU.

Olivia Rowley

Olivia Rowley

Olivia Rowley is conducting her PhD at JCU, and is primarily advised by Jamie Seymour. She is using a combination of experiments and modeling approaches to describe the environmental drivers of deadly jellyfish in Australia. Olivia can be contacted at


Rowley, OC, RL Courtney, SA Browning, JE Seymour. 2020. Bay watch: Using unmanned aerial vehicles (UAV’s) to survey the box jellyfish Chironex fleckeri. PLoS One, 15: e0241410.

Deppe, L, O Rowley, LK Rowe, N Shi, N McArthur, O Gooday, SJ Goldstein. 2017. Investigation of fallout events in Hutton’s shearwaters (Puffinis huttoni) associated -with artificial lighting. Notoris, 64: 181-191.

Hemchandranauth Sambhu

Hemchandranauth Sambhu

Hemchandranauth conducted his PhD research at JCU, which focused on a combination on ecological and sociological research in Guyana and Australia. He compared patterns of butterfly abundance and community composition across different landscapes, wrote a checklist for butterflies of Australia, and participated or led a number of outreach events for the general public and schools.

Resulting publications:

Sambhu, H, A Nankishore, S Turton, TD Northfield. 2018. Trade-offs for butterfly alpha and beta diversity in human-modified landscapes and tropical rainforests. Ecology and Evolution. 8: 12918-12928.

Sambhu, H, A Nankishore. 2018. Butterflies (Lepidoptera) of Guyana: A compilation of records. Zootaxa, 4371: 1-187.

Sambhu, H, TD Northfield, A Nankishore, A Ansari, S Turton. 2017. Tropical rainforest and human-modified landscapes support unique butterfly communities that differ in abundance and diversity. Environmental Entomology, 46: 1225-1234.

Jessa Thurman

Jessa Thurman

Jessa joined the lab in JCU first on an international Watson Fellowship, and then as a Fulbright Fellow. She worked on biological control of pests in cacao by green weaver ants and Anastatus sp. wasps. She is now a PhD student with Michael Furlong at University of Queensland, in Brisbane Australia.

Resulting publications:

Thurman, JH, TD Northfield, WE Snyder. 2019. Weaver ants provide ecosystem services to tropical tree crops. Frontiers in Ecology and Evolution, 7:21.

Thurman, JH, DW Crowder, TD Northfield. 2017. Biological control agents in the Anthropocene: Current risks and future options. Current Opinion in Insect Science, 23: 59-64.

Nicolás Younes Cárdenas

Nicolás is conducted his PhD at JCU and is primarily advised by Karen Joyce. He is combining novel statistical approaches and Landsat data to describe changes in mangrove phenology over the last 30 years. He is now a postdoctoral research at Australian National University.

Resulting publications:

Younes, N, TD Northfield, KE Joyce, S Maier, NC Duke, L Lymburner. In press. A novel approach to modelling mangrove phenology from satellite images: A case study from Northern Australia. Remote Sensing.

Younes, N, KE Joyce, TD Northfield, SW Maier. 2019. The effects of water depth on estimating fractional vegetation cover in mangrove forests. International Journal of Applied Earth Observations and Geoinformation. 83: 101924.

Younes Cárdenas, N, KE Joyce, SW Maier. 2017. Monitoring mangrove forests: Are we taking full advantage of technology? International Journal of Applied Earth Observation and Geoinformation, 63. pp. 1-14