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The University of Florida and Davey Tree Experts Present

Cutting Edge Research for Tree Care Professionals

Wednesday, February 28, 2024 / 8:00 AM - 5:00 PM

The Davey Tree Expert Company and the University of Florida both have a rich history of conducting research in the field of arboriculture. The purpose of the conference is to share each group’s cutting-edge work as it relates to the management of trees in the urban landscape. The information is meant for industry professionals, educators, extension agents, academics, and the general public. The research covered during this one-day event includes: urban tree pests, disease, and management, as well as palm health management, the impacts of climate change, tree risk, and root damage. Please join us for a day of research, networking, and working toward collaborations aimed at solving current and future arboricultural issues. This event will take place at the Straughn IFAS Extension Professional Development Center in Gainesville, Florida, USA.


Certified Arborist: 6

Utility Specialist: 0

Municipal Specialist: 6

BCMA - Science: 2

BCMA - Practice: 2.5

BCMA - Management: 1.5

TW Climber Specialist: 6

TW Aerial Lift Specialist: 6

Poster session info: For anyone who would like to take part in the poster session, presenters should email their poster title, bio, and headshot to Ryan Klein ( by February 1st. Final submissions are due February 14th.


  • 8:00 - 8:30 - Welcome - Dan Herms

    Dan Herms

    Dan Herms

    Dan Herms is Vice President of Research and Development at The Davey Tree Expert Company. Prior to joining Davey in 2018, he was a professor in the Department of Entomology at Ohio State University for 21 years where his research and outreach programs focus on the ecology and management of trees, including interactions with insects, soils, and climate. From 1984-1996, he worked at The Dow Gardens, a public garden in Midland, MI, where he directed the plant health care program. He received his B.S. in Landscape Horticulture from Ohio State University, his M.S. in Horticulture and Entomology from Ohio State University, and his Ph.D. in from Michigan State University in Entomology.

  • 8:30 - 9:00 - Managing Staining of Black Olives in South Florida – A.D. Ali

    A.D. Ali

    Dr. A.D. Ali

    Managing Staining of Black Olives in South Florida

    Black olive trees are an important component of landscapes in South Florida and the Caribbean. Two pests, a moth and an eriophyid mite, result in unacceptable staining of areas under the trees. A 4-year study was conducted to evaluate the efficacy of selected products for managing pests and reducing staining.

    Dr. Ali has over 40 years of experience in the Green Industry. For the past 23 years, he oversaw Davey technical support programs in the US and Canada. He is a founding team member of Davey Global Consulting. He is a Board-Certified Master Arborist, TRAQ Qualified and served on the Board of Directors, Florida Chapter ISA as well as being Past President of the Chapter. Dr. Ali has written a book on Pest Management in the Landscape. In addition, he has presented 130 scientific and training seminars and authored more than 300 scientific and trade-oriented articles.

    Staining from Black Olive street trees in Coral Gables, FL

    Staining from Black Olive street trees in Coral Gables, FL

    Trunk injecting Black Olive to manage mites

    Trunk injecting Black Olive to manage mites


  • 9:00 - 9:30 - Trees, People, and Management Conflicts in the Urban Landscape - Ryan Klein

    Ryan Klein

    Dr. Ryan Klein

    Trees, People, and Management Conflicts in the Urban Landscape

    The talk provides an overview of multiple studies that address issues associated with the management of urban trees. Specifically, the research presented outlines potential arboricultural opportunities to address current and future tree care challenges. The topics covered include tree risk assessment, the impacts of natural disasters on urban tree survival, mitigating the negative effects of climate change, and promoting healthy more resilient urban forests.

    Dr. Ryan Klein is an Assistant Professor of Arboriculture at the University of Florida. He has 12 years of experience in the nursery and tree care industry. Ryan has received his International Society of Arboriculture (ISA) Arborist Certification, Quantified Tree Risk Assessment (QTRA) Certification, ISA Tree Risk Assessment Qualification (TRAQ), and Florida ISA Prescription Pruning Qualification (PPQ). Ryan is the Past President of the Arboricultural Research and Education Academy (AREA) and sits on the Florida Chapter of the ISA Board of Directors and Education Committee. His research focuses on tree risk assessment and risk perception, as well as the impacts of natural disasters and climate change on urban tree populations.

    Tree topping and restoration project

    Tree topping and restoration project

    Correcting root defects by shaving the root ball

    Correcting root defects by shaving the root ball

    Field trial comparing nursery stock quality - image of root defects

    Field trial comparing nursery stock quality – image of root defects

    Irrigation bag cost benefit analysis field plots

    Irrigation bag cost-benefit analysis field plots

    Severe crack / inclusion identified during a level 1 drive-by tree risk assessment in Sheboygan, WI

    Severe crack/inclusion identified during a level 1 drive-by tree risk assessment in Sheboygan, WI

  • 9:30 - 10:00 - Sonic Tomography: Technology and Case Studies – Sarah Ruark

    Sarah Ruark

    Sarah Ruark

    Sonic Tomography: Technology and Case Studies

    Sonic tomography is a technique used to detect decay or cavities inside trees. It is relatively non-invasive utilizing sound waves detected by sensors placed around the trunk. The equipment, methodology and case studies will be presented.

    Sarah Ruark is a Technical Advisor for the Davey Institute and has been with Davey since 2019. She graduated summa cum laude from the University of Tennessee with a BS in Plant Biology in 2006. She has a Master’s degree in Plant Pathology from North Carolina State University (2008). She is based in Tyler, TX and provides technical advice to offices in Texas, Colorado, and Tennessee. Her areas of expertise are molecular diagnostics and tree risk assessment (sonic tomography). She is Tree Risk Assessment Qualified (TRAQ) through the International Society of Arboriculture (ISA).

    Sonic tomography testing

    Sonic tomography testing

    Sonic tomogram

    Sonic tomogram

    Testing decay with sonic tomography

    Testing decay with sonic tomography

10:00 - 10:30 - Break with Posters and Attendee Research Question Generation


  • 10:30 - 11:00 - Root Regrowth After Trenching - Andrew Koeser

    Andrew Koeser

    Dr. Andrew Koeser

    Root Regrowth After Trenching

    Dr. Andrew Koeser is an Associate Professor of Landscape and Urban Tree Management at the Gulf Coast Research and Education Center in the Tampa Bay Metro Area. He researches topics related to urban tree biodiversity, policy, storm response, and construction damage and works closely with urban foresters, arborists, and landscapers to create greener communities across the state. Andrew is the father of four daughters and enjoys cycling, martial arts, and photography in his spare time.

  • 11:00 - 11:30 - Pre-emergent Herbicides Evaluation: A multi-state study – Manny Nassar

    Manny Nassar

    Manny Nassar

    Pre-emergent Herbicides Evaluation: A multi-state study

    Pre-emergent herbicides are a key tool for reducing weed pressure in commercial landscapes. A season-long study was conducted at four separate locations in the Midwest and north Florida to evaluate products to reduce dependency on post-emergent herbicides.

    Manny Nassar is a Technical Advisor with The Davey Institute, providing technical support and education in Landscape Management Best Practices, Arboriculture, Plant Health Care, field diagnostics, research, and new chemistry updates to all Davey Tree Commercial Landscape Offices in the southeast, and mountain regions. Prior to being appointed a Technical Advisor, Manny spent 13 years managing large commercial landscape projects, office, warehouse, government, and corporate facilities for Davey in Central and South Florida. 

    Preemergent herbicide study plots

    Pre-emergent herbicide study plots

    applying preemergent herbicides

    Applying pre-emergent herbicides

  • 11:30 - 12:00 - The Most FAQ’s on Palm Health, Nutrition and Management - Mica McMillan

    Mica McMillan

    Dr. Mica Millan

    The Most FAQ’s on Palm Health, Nutrition and Management

    This presentation will update attendees on the most frequently asked questions that are received in the palm nutrition lab. Topics will include transplant issues, common nutrient deficiencies, over-fertilization, water management and vertebrate and pest destruction. Survey data from Palm Short Courses will be also be shared to highlight trends in the industry.

    Dr. McMillan is the Assistant Professor of Palm Horticulture at the Fort Lauderdale Research and Education Center. As a researcher in the agriculture, turfgrass and media industries, she focused on developing chemistries to improve plant and soil health. Dr. McMillan’s research will primarily focus on palm and ornamental plants from seed to establishment under a variety of environmental and edaphic conditions such as salinity, drought and fertility. Dr. McMillan earned her B.S. and M.S. from Auburn University and her Ph.D. from the University of Florida. 


12:00 - 1:00 - Lunch


  • 1:00 - 1:30 - Urban Forest Management Planning: Understanding the social and ecological context - Michael Andreu

    Michael Andrue

    Dr. Michael Andreu

    Urban Forest Management Planning: Understanding the social and ecological context. 

    Dr. Andreu will discuss the process of developing a strategic urban forest management plan that incorporates both social and ecological data.  Increasingly we are realizing that urban forest management requires a broader understanding than just knowing about the trees.  An effective and sustainable urban forest management program must address three major components: social systems, governance systems, and ecological systems. The social component provides the justification for the plan by demonstrating value to the people who live and utilize the forest. The governance component provides guidance to responsible entities on how, when and where management activities will occur. The ecological component addresses the dynamic nature of the system, which is the reason this process is different than simply managing other infrastructure such as transportation systems, sewer systems or electrical grids. 

    Dr. Michael Andreu is an Associate Professor of Forest Systems in the School of Forests, Fisheries, & Geomatics Sciences.  He currently serves as the SFFGS Extension Coordinator, is the Co-Chair of the IFAS Urban Forestry Extension Council, co-chair of the IFAS Invasive Species Extension Council, a Member of the UF/IFAS Climate & Carbon Extension Educators Working Group, PI of the FL Land Steward Program and the UF Native Plant Nursery.  He has been involved in urban forest management planning for over 2 decades. 

  • 1:30 - 2:00 - Biochar Lifecycle in the Green Industry – Chris Fields-Johnson

    Chris Fields-Johnson

    Chris Fields-Johnson

    Biochar Lifecycle in the Green Industry

    Biochar Lifecycle in the Green Industry. Biochar is an emerging soil amendment and plant growth medium which has many applications including carbon sequestration and water filtration. Because biochar can be made from urban green waste and used to improve plant and stormwater performance in the built environment, a lifecycle can be designed with a positive feedback loop for plants and water while sequestering atmospheric carbon at every step. Introductory information on biochar as well as many studies looking at aspects of its lifecycle will be presented.

    Chris Fields-Johnson is the Tree Conservation Specialist and Technical Advisor for the Atlantic region for the Davey Institute, providing technical support to Davey plant healthcare operations in the region between Philadelphia and Atlanta and expertise in soil and root zone management across the United States and Canada. He holds a Ph.D. and an M.S. in Crop and Soil Environmental Sciences, and he graduated Summa cum laude as the Outstanding Senior in Natural Resources with a B.S. in Forest Resource Management from Virginia Tech in 2008. His graduate work included research on the reforestation of surface-mined lands in the Appalachian coalfield and the development of biochar to improve the rehabilitation of impaired soils. His current research is on recycling urban forest green waste to optimize plant-soil-water relationships. He lives with his wife and two children in Charlottesville, Virginia where they enjoy hiking, cycling, and kayaking in the Blue Ridge Mountains.

  • 2:00 - 2:30 - Assessment of rot in palms - Braham Dhillon

    Braham  Dhillon

    Braham Dhillon

    Assessment of rot in palms

    Description: The talk will discuss fungal pathogens that cause rot in palms. How do these pathogens get established and how does the disease progress. What type of rot/damage do these pathogens cause. What methods are available to detect these pathogens and diagnose the disease in the landscape. Various case studies will be used to highlight the utility of sonic tomography in detecting rot in palms.

    Braham Dhillon is an Assistant Professor of Plant Pathology at the University of Florida, Fort Lauderdale Research and Education Center. He received his Ph.D. from Purdue University and did his undergraduate studies at Punjab Agricultural University, India. He is a molecular plant pathologist working on fungal pathogens of palms and other tropical plants. His research program focuses on leveraging fungal pathogen biology to understand questions related to host-pathogen interaction, disease etiology and pathosystem evolution. Projects involve building effective diagnostics tools, uncovering pathogen diversity, evaluating cultural, and biological control of fungal pathogens, and utilizing novel approaches to assess host response to fungal colonization.

2:30 - 3:00 - Break with Posters and Attendee Research Question Generation


  • 3:00 - 3:30 - Establishing and managing pollinator habitat using drone technology on ROWs - Adam Baker

    Adam Baker

    Dr. Adam Baker

    Establishing and managing pollinator habitat using drone technology on ROWs

    Transitioning ROWs from compliance-based management to suitable habitat for pollinators can be difficult but can lead to environmental stewardship certifications, positive public perception, and reduced inputs. In this study we compared drone seeding with more traditional seeding methods, seed mixes with pre-emergent and post-emergent herbicides to reduce competition with grasses, and management regimes to maintain biodiverse habitats.

    Dr. Adam M. Baker conducts research and provides educational training as a Research Entomologist with the Davey Institute. His expertise is in pollinator ecology, conservation, and the responsible management of pests in the urban landscape. Adam’s dissertation explored the ecology and conservation of the iconic monarch butterfly, applying ecological theory to conservation plantings. He has published research articles on various insect taxa, and has provided numerous seminars at scientific, stakeholder, and green industry conferences. 

    Drone seeding of pollinator habitats

    Drone seeding of pollinator habitats

    Pollinator Habitat

    Pollinator Habitat

  • 3:30 - 4:00 - Current management practices for lethal bronzing in palms - Brian Bahder

    Brian Bahder

    Brian Bahder

    Current management practices for lethal bronzing in palms

    Description: Lethal bronzing disease is a fatal infection of a variety of palm species in Florida. Traditional management options are not sustainable over large areas in urban settings. Current research on the vector and plant volatiles highlights new areas for the development of improved management options.

    Dr. Bahder specializes in insect vector ecology, specifically in vector discovery of new and emerging pathogens that cause economic loss in agricultural and ornamental cropping systems as well as understanding the evolutionary relationships and molecular mechanisms that determine the ability of species to transmit pathogens.  His current research interests include the epidemiology of phytoplasmas infecting palms as well as other common tropical ornamental plants and their associated diseases and insect pests and developing management strategies to reduce economic losses.

  • 4:00 - 4:30 - Efficacy of Aphidoletes predator releases to mitigate aphid populations on linden street trees – Thomas Whitney

    Thomas Whitney

    Dr.  Thomas Whitney

    Efficacy of Aphidoletes predator releases to mitigate aphid populations on linden street trees

    Description: Aphids and their honeydew are annual nuisances for urban trees. Arborists cannot apply pesticides on many aphid-loving species due to pollinator concerns, which leads to inaction. Augmentative biocontrol (e.g. predator releases) has proven effective in greenhouses, but its usefulness in complex urban environments is unclear. In cooperation with City of Portland, we are assessing whether Aphidoletes midge releases on linden street trees effectively mitigate aphid populations.

    Dr. Thomas Whitney is a Technical Advisor with the Davey Institute, providing support for the Pacific Northwest US and Western Canada. He has a BS in Biology, an MS in Entomology, and a PhD in Forest Resources. He specializes in insect pests of trees.

    Street tree aphid biocontrol study, City of Portland

    Street tree aphid biocontrol study, City of Portland

    Aphid infested linden street trees

    Aphid infested linden street trees


  • 4:30 - 5:00 - Closing Remarks - Dean Andra Johnson

    Dr. Andra Johnson

    Dr. Andra Johnson

    The Value of Public/Private Relationships

    Dr. Johnson accepted the role of Dean and Director of UF/IFAS Cooperative Extension in November 2021. Prior to accepting the position of Dean and Director of UF/IFAS Cooperative Extension, Dr. Johnson served as a tenured faculty member in the College of Agricultural Sciences’ Department of Ecosystem Sciences and Management and the Associate Director of Extension for The Pennsylvania State University Cooperative Extension Service. In this role, he provided senior-level leadership, supervision and visioning as well as daily oversight in the development and implementation of a customer-centric, innovative program strategy to meet the mission of a land-grant University. He oversaw seven programming units consisting of: Food, Families and Health; Agronomy and Natural Resources; Energy, Business and Community Vitality; Horticulture; 4-H Youth Development; and Animal Systems. These seven areas, led by assistant directors of programs, encompassed thirty program teams. 

    Prior to this role, Dr. Johnson served as Vice Chancellor for Research and Technology Development at the Southern University Agricultural Research and Extension Center in Baton Rouge, Louisiana, where he oversaw the land-grant research portfolio and budget. In this role, he worked with Extension leadership to help chart a new research vision that would meet the needs of Louisiana’s clientele.  

    Dr. Johnson also served as Assistant Director of Research at Alcorn State University School of Agricultural Research, Extension, and Applied Sciences in Lorman, Mississippi., where he oversaw the agricultural research budget and five research and Extension centers which included: ASU Experimental Research Station, Mississippi River Research Center, Swine Development Center, Conservation Center, and the Small Farm Development and Agribusiness Center. 

    Finally, Dr. Johnson spent over 13 years as a tenured faculty member at The Southern University and A&M College in Baton Rouge, Louisiana, in the Department of Urban Forestry before becoming Assistant Research Director at Alcorn State University. During this time, he conducted research and taught classes in Natural Resources and Urban Forestry.  

    Dr. Johnson received his M.S. and Ph.D. degrees in Forestry Resources from the Pennsylvania State University, University Park, Pennsylvania. He also received a B.S. in Urban Forest Management from Southern University and A&M College in Baton Rouge, Louisiana.

UF/Davey Poster Session Presenters


Lucas Altarugio

Presenter: Lucas Altarugio

Title: Evaluate efficiency of tomography methods to detect rot in palms

Bio: Lucas Altarugio is a Post-Doctoral Fellow, sponsored by Davey Tree, working at the University of Florida, Fort Lauderdale Research and Education Center in Davie, FL. He received his PhD in Soils and Plant Nutrition from University of Sao Paulo, Brazil. He has undergraduate degrees in Agricultural Engineering (University of Sao Paulo), and Biotechnology from Federal University of Alfenas, Brazil. He research experience is in enzymology, soil fertility, and plant nutrition for crops like sugar cane, soybeans, and corn. In his PhD, he studied the effectiveness of foliar nitrogen in sugarcane application using isotopic techniques, biochemical analysis, and field trials. He was a Project Manager in University of Sao Paulo, coordinating the soil fertility and sugarcane fertilization research program across 3 million hectares. He was a Product Developer Specialist at Centro de Tecnologia Canavieira (CTC), managing research projects with sugarcane breeding, variety positioning, crop management and GMO technologies.

Thiago Campos

Presenter: Thiago Campos

Title: Euterpe edulis Martius (Jussara palm) seedling growth improved by Rhizobacteria inoculation

Bio: I'm an Agricultural Engineer who graduated from the Federal University of Uberlândia (2018) with a Seed Science and Technology specialization from the Federal University of Pelotas (2019). Masters in Crop Production from the State University of Goiás (2020). Currently, pursuing a Ph.D. in Agronomy (Crop Production) at São Paulo State University Júlio de Mesquita Filho, UNESP, Jaboticabal Campus, since 2020, with a sandwich exchange program at the University of Florida, focusing on Environmental Horticulture (2023). Experience in seed and seedling production and technology, with expertise in native and horticulture species, plant physiology, and renewable resources for sustainable agricultural production. During my academic career, I have conducted experiments to improve seed and seedling quality processes and collaborated with researchers and agricultural professionals in different areas to implement conservation methods for endangered species.

Maria Cuervo

Presenter: Maria Cuervo

Title: The importance of species and microhabitat in plant-environment interactions

Bio: María Cuervo is a PhD student in the laboratory of Dr. Grace John in the College of Liberal Arts and Sciences in the Biology Department at the University of Florida. She received her Bachelor of Science in Biology in 2023 from the Universidad Nacional de Colombia, where her research focused on thermal tolerance of street trees in Bogotá, Colombia. María's dissertation work builds on this expertise and explores the mechanistic drivers of urban tree responses to abiotic stress.

Adam Dale

Presenter: Adam Dale

Title: Balancing pest management, biodiversity conservation, and tree health across an urban forest

Bio: Adam Dale is an Associate Professor, State Extension Specialist, and Associate Chair for Extension in the UF IFAS Entomology and Nematology Department. His research program focuses on insect ecology and management on plants in urban landscapes, working to identify strategies for suppressing pests, increasing biodiversity, and promoting plant health. Through his Extension programs, Dale translates the latest integrated pest management research into application and delivers it to industry professionals throughout the Southeast via in-person trainings, virtual workshops, and industry publications.

Andrew Koeser

Presenter: Andrew Koeser

Title: Improving community hurricane resilience through a comprehensive assessment of tree species wind resistance.

Bio: Andrew Koeser is an Associate Professor at the University of Florida Gulf Coast Research and Education Center near Tampa Florida. Andrew researchers tree biomechanics and storm response, trees and construction, and urban forest policy. He earned his PhD and MS degrees from the University of Illinois and his BS from the University of Wisconsin – Stevens Point.

Authors: Allyson Salisbury and Andrew Koeser et al.

Allyson Salisbury

Presenter: Allyson Salisbury

Bio: Allyson Salisbury is an Urban Forestry Assistant Professor at Rutgers University. Her research interests include urban ecology, soil science, hurricanes, and stormwater. She earned her PhD and MS degrees from Rutgers University and her BS from Susquehanna University.

Vania Pereira

Presenter: Vania Pereira

Title: Fertilization Technologies  for Commercial Production of Saw Palmetto (Serenoa repens)

Bio: I grew up on a farm in the south of Brazil. The experiences on the farm led me to choose agronomy engineer as my bachelor's degree. During my undergrad, I did one year as an exchange student at Illinois State University, where I started working more in horticulture. After finishing my degree in Brazil, I returned to ISU for my master's in Agriscience, working with annual bedding plants and beneficial nutrients. This led me to my Ph.D. at UF in environmental horticulture, working with the native palm saw palmetto. My current project objective is to create protocols for the commercial production of saw palmetto involving micropropagation, seed biology, greenhouse growth, fertilization in the greenhouse and field, and prescribed fire management. 

Teagan Young

Presenter: Teagan Young

Title: Introduction to Evaluating the Impacts of Climate Change on Urban Tree Performance and Survival

Bio: Hi there! I come from the lovely town of Kalamazoo, MI, where my love for taking care of nature through horticulture first took root. In 2019, I made my way down to Gainesville, FL, enticed by the opportunity to join the respected University of Florida's Environmental Horticulture program. Fast forward to 2021, and I proudly graduated with my Master’s degree, specializing in the propagation of native plant species. Building on this achievement, I embarked on my PhD journey in 2022, eager to delve deeper into the realms of environmental horticulture. Currently, I'm deeply engaged in studies related to climate change, a growing concern over the past five decades.

Location: Straughn Center, 2142 Shealy Drive, Gainesville, FL

Date: February 28, 2024

Time: 8:00 am - 4:45 pm