PROTECTING HUMAN AND ENVIRONMENTAL HEALTH WITH IPM FOR URBAN TREES

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: OTHER GRANTS
• Reporting Frequency: Annual
• Accession No.: 1010900
• Grant No.: 2016-70006-25827
• Cumulative Award Amt.: $324,979.00
• Proposal No.: 2016-07590
• Project Start Date: Sep 1, 2016
• Project End Date: Aug 31, 2021
• Grant Year: 2016
• Program Code: [ARDP]- Applied Research and Development Program

Recipient Organization
NORTH CAROLINA STATE UNIV
(N/A)
RALEIGH,NC 27695

Performing Department
Entomology

Non Technical Summary
Urban trees often have more pests and are less healthy than rural trees having negative economic consequences for municipalities that care for tens or hundreds of thousands of trees and negative environmental and human health consequences as current pest management relies primarily on pesticides. Our research shows scale insect pest density on common urban trees increases due to stress caused by impervious surface cover and poor biological control. Putting the 'right plant in the right place' to reduce stress is a cornerstone of IPM. The problem we address is that tree care professionals have few decision-making tools for site selection or cultural IPM tactics to reduce stress and pest establishment. To improve IPM of urban trees our objectives are to determine:1) How tree diversity affects pest abundance and biological control;2) How drought (interacting with impervious surface cover and regional climate) affect tree growth and pest susceptibility; and3) Best impervious surface thresholds for common urban tree species.Using national tree inventory data we will make regionally specific planting and management recommendations for the 20 most common urban tree species based on local tree diversity and impervious surface cover in order to reduce pest damage and increase tree and ecosystem health. Our team of research, extension, and US Forest Service personnel will develop and disseminate a variety of extension resources. This proposal includes a Center of Excellence Justification.

Animal Health Component

100%

Research Effort Categories

Basic

(N/A)

Applied

100%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
216	0699	1130	100%

Knowledge Area
216 - Integrated Pest Management Systems;

Subject Of Investigation
0699 - Trees, forests, and forest products, general;

Field Of Science
1130 - Entomology and acarology;

Keywords

integrated pest management

urban trees

red maple

scale insects

Goals / Objectives
The problem we address in this proposal is that pest management on urban trees relies almost entirely on insecticide applications. Tree care professionals do not have cultural IPM tactics or decision making tools to select optimal planting sites or reduce environmental stress on new and established trees. This has real economic consequences for municipalities that care for tens or hundreds of thousands of trees. Our objective is to develop cultural IPM tactics and decision making tools that will improve tree growth and survival while reducing insecticide inputs that pose risks to human and environmental health. Specifically we will:1) Determine how urban tree diversity affects pest abundance and biological control;Rationale: Plant species diversity has well-known benefits for increasing biological control and reducing pest establishment. Therefore, including tree diversity in planting and management decisions could reduce pest establishment.2) Determine how drought interacts with impervious surface cover and regional climate to affect tree growth and pest susceptibility: Rationale: Urban trees are almost universally drought stressed from poor soil, impervious surface, and restricted root zones. The intensity of stress that results will depend on the local environment (tree site) and the background climate (latitude). We will test two watering regimens as cultural IPM tactics in three cities to make regionally appropriate recommendations.3) Develop impervious surface thresholds for urban tree species that are common throughout the eastern US: Rationale: We developed impervious surface thresholds to inform site selection when planting red maples or including red maples in landscape designs. We will use tree inventories from cities in around the country to create regionally specific impervious surface thresholds for the 20 most common urban tree species.

Project Methods
Objective 1: Determine how urban tree diversity affects pest abundance and biological control. Methods: To determine how street tree diversity affects pest abundance, biological control, and tree health we will conduct a factorial experiment with two monotypic treatments (monotypic plantings of red maple or willow oak) and two diverse treatments (plantings of at least four tree species that include a red maple or willow oak) in Raleigh, NC. We will select eight sites that represent each diversity treatment (32 sites total) using a randomized sampling procedure stratified by geography and impervious surface cover as in [4, 9].On each focal tree we will assess scale insect density by collecting two branches from each cardinal direction and counting scales on the growth from the previous year as indicated by bud scars.To further assess pest and natural enemy abundance we will beat-sample foliage from each focal tree (as in[9]) to collect pests and predators, such as lady beetles, spiders, predatory Hemipterans, and lacewing larvae that would not be collected on branch samples above.Objective 2: Determine how drought interacts with impervious surface cover and regional climate to affect tree growth and pest susceptibility.All trees used in the study will be property of Newark, DE, Raleigh, NC, or Jacksonville, FL and located in the right-of-way, up to 10 m from the street. To select study sites, we will use methods similar to Objective 1 and as in [4, 9].At each site we will randomly assign each tree to one of three water treatments: high water addition, low water addition, or ambient. Based on preliminary data, trees receiving only ambient rainfall have xylem water potentials indicating drought stress. We will water trees by placing two (based on previous experiments using trees this DBH[8]) TreeGator ® slow-release watering bags (Spectrum Products Inc., Youngsville, NC) around their base. To determine how impervious surface and watering treatments affect tree drought stress, we will measure predawn and midday xylem water potential of each tree in June, July, and August using a pressure chamber (PMS Instrument Company, Albany, OR)Objective 3: Develop impervious surface thresholds for urban tree species that are common throughout the eastern US. We will determine which species decline or thrive at different amounts of impervious surface cover and develop impervious surface thresholds for each. To do so, we will use existing municipal street-tree inventories in conjunction with impervious surface layers available from the USGS National Land Cover Database.

Progress 09/01/16 to 08/31/21

Outputs
Target Audience: Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Training of graduate students, postdocs, undergraduates, and stakeholders. We have trained graduate students under this project and undergraduates in data collection, experimental design, IPM, and entomology. Training of undergraduates and extension clientele have been restricted in recent years due to the covid pandemic. How have the results been disseminated to communities of interest? The COVID pandemic reduced opportunities to interact with stake holders and diseminate results. However we were able to remotely diseminate results to stakeholders including urban foresters, landscapers, and arborists via extension presentations, industry publications, and extension resources such as fact sheets and websites. We have also published peer-reviewed papers and given presentations at scientific meetings. ? What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? 1) We completed an analysis of tree diversity in Raleigh NC and how tree diversity affects pest density, natural enemies, and biological control in tree canopies. This work is completed with a draft of the peer-reviewed publication. 2) These data are complete. We have already published some of the findings from this objective. 3) Data are complete with a draft publication underway. We have already published some of the findings related to pests, natural enemies, and impervious surface cover.

Publications

• Type: Book Chapters Status: Published Year Published: 2020 Citation: Martinson, H.M., Raupp, M.J., and Frank, S.D. (2020) How urban forest composition shapes the structure and function of arthropod communities. In P. Barbosa (Ed.), Urban ecology: Its nature and challenges (pp.15-36). CAB International.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Just, M.G., Dale, A.G., and Frank, S.D. (2020) Gloomy scale (Hemiptera: Diaspididae) ecology and management on landscape trees. Journal of Integrated Pest Management, 11(1): 24; 1-9.
• Type: Journal Articles Status: Published Year Published: 2021 Citation: Backe, K. , Rousselet, J., Bernard, A., Frank, S.D., and Roques, A. (2021). Human health risks of invasive caterpillars increase with urban warming. Landscape Ecology, https://doi.org/10.1007/s10980-021-01214-w.

Progress 09/01/19 to 08/31/20

Outputs
Target Audience: Our target audience includes extension professionals, urban foresters, landscape professionals, and other who manage urban trees and their pests. We have reached other scientists through peer-reviewed publications and scientific presentations and national meetings and universities. We reached extension professionals with extension educational resources and presentations. We have also reached stakeholders such as urban foresters, arborists, and landscapers with extension presentations. ? Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Training of graduate students, postdocs, undergraduates, and stakeholders. How have the results been disseminated to communities of interest? The COVID pandemic reduced opportunities to interact with stake holders and diseminate results. However we were able to remotely diseminate results to stakeholders including urban foresters, landscapers, and arborists via extension presentations, industry publications, and extension resources such as fact sheets and websites. We have also published peer-reviewed papers and given presentations at scientific meetings. What do you plan to do during the next reporting period to accomplish the goals?We will finish analyses and publications.

Impacts
What was accomplished under these goals? Objective 3. We developed impervious surface thresholds for the southern region for red maples and published our findings. We have collected data on 6 other tree species and are calculating thresholds for them.

Publications

• Type: Journal Articles Status: Published Year Published: 2020 Citation: Lahr, E.C., Backe, K.M. , and Frank, S.D. (2020) Intraspecifc variation in morphology, physiology, and ecology of wildtype relative to horticultural varieties of red maple (Acer rubrum). Trees  Structure and Function, https://doi.org/10.1007/s00468-019-01942-2.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Just, M.G., and Frank, S.D. (2020) Thermal tolerance of gloomy scale (Hemiptera: Diaspididae) in the Eastern United States. Environmental Entomology, nvz154, https://doi.org/10.1093/ee/nvz154.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Frank, S.D. and Just, M.G. (2020) Can cities activate sleeper species and predict future forest pests? A case study of scale insects. Insects, 11(3): 142. https://doi.org/10.3390/insects11030142.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Frank, S.D. (2020) Review of the direct and indirect effects of warming and drought on scale insect pests of forest systems. Forestry: An International Journal of Forest Research, https://doi.org/10.1093/forestry/cpaa033.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Just, M.G., Dale, A.G., and Frank, S.D. (2020) Gloomy scale (Hemiptera: Diaspididae) ecology and management on landscape trees. Journal of Integrated Pest Management, 11(1): 24; 1-9. DOI: 10.1093/jipm/pmaa028.

Progress 09/01/18 to 08/31/19

Outputs
Target Audience:Our target audience includes extension professionals, urban foresters, landscape professionals, and other who manage urban trees and their pests. We have reached other scientists through peer-reviewed publications and scientific presentations and national meetings and universities. We reached extension professionals with extension educational resources and presentations. We have also reached stakeholders such as urban foresters, arborists, and landscapers with extension presentations. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Training of graduate students, postdocs, undergraduates, and stakeholders. How have the results been disseminated to communities of interest?Results have been diseminated to stakeholders including urban foresters, landscapers, and arborists via extension presentations, industry publications, and extension resources such as fact sheets and websites. We have also published peer-reviewed papers and given presentations at scientific meetings. What do you plan to do during the next reporting period to accomplish the goals?We will continue working on objective 1 to refine and finish our analyses. We will finish data collection for objective 2 and analyze data to begin new publications.

Impacts
What was accomplished under these goals? Objective 1: We have continued to identify suitible sites and hone our GIS analyses of tree diversity and landscape composition. Objective 2. The experiment was implemented during the first summer with all the sites selected in each of the three cities. Three trees were selected at each site and randomly assigned as either the unwatered, watered once per week, or watered twice per week treatments. We have maintained these treatment regimens throughout the experiment and continue watering in 2019. Scale insect and tree data were collected each year and will be collected again in fall 2019. Physiological measurements of tree stress and photosynthesis have also been collected. Objective 3. We developed impervious surface thresholds for the southern region for red maples and published our findings. We have collected data on 6 other tree species and are calculating thresholds for them.

Publications

• Type: Journal Articles Status: Published Year Published: 2019 Citation: Long, L.C. , DAmico, V., Frank, S.D. (2019) Urban forest fragments buffer trees from warming and pests. Science of the Total Environment, 658: 1523-1530. https://doi.org/10.1016/j.scitotenv.2018.12.293.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Just, M.G., Long, L.C. , Dale, A.G., and Frank, S.D. (2019) Urbanization drives unique latitudinal patterns of insect herbivory and tree condition. Oikos. https://doi.org/10.1111/oik.05874.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Frank, S.D., Backe, K.M. , McDaniel, C.*, Green, M., Widney, S., Dunn, R.R. (2019) Exotic urban trees conserve similar natural enemy communities to native congeners but have fewer pests. PeerJ: 7:e6531 https://doi.org/10.7717/peerj.6531.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Just, M. G., & Frank, S. D. (2019). Evaluation of an Easy-to-Install, Low-Cost Dendrometer Band for Citizen-Science Tree Research. Journal of Forestry, 117, 317-322.

Progress 09/01/17 to 08/31/18

Outputs
Target Audience: We have reached other scientists through peer-reviewed publications and scientific presentations and national meetings and universities. WE reached extension professionals with extension educational resources and presentations. We have also reached stakeholders such as urban foresters, arborists, and landscapers with extension presentations. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Training of graduate students, postdocs, undergraduates, and stakeholders. How have the results been disseminated to communities of interest? Results have been diseminated to stakeholders including urban foresters, landscapers, and arborists via extension presentations, industry publications, and extension resources such as fact sheets and websites. What do you plan to do during the next reporting period to accomplish the goals? Continue conducting experiments in all three objectives as described in the proposal. The watering experiment is about ending for this year and will begin again in 2019. We have collected scale insect data from all the trees and will continue in the coming year. We will continue collecting data on different tree species to establish impervious surface thresholds.

Impacts
What was accomplished under these goals? Objective 1: We have established study sites. Objective 2. The experiment was implemented two years ago with all the sites selected in each of the three cities. Three trees were selected at each site and randomly assigned as either the unwatered, watered once per week, or watered twice per week treatments. Scale insect and tree data were collected each year. Trees have been watered for two years with insect and physiology data each year. Objective 3. We developed impervious surface thresholds for the southern region for red maples and colected data on 6 other tree species to begin calculating thresholds.

Publications

• Type: Journal Articles Status: Published Year Published: 2018 Citation: Dale, A.G. and Frank, S.D. (2018) Urban plants and climate drive unique arthropod interactions with unpredictable consequences. Current Opinion in Insect Science, 29: 27-33. https://doi.org/10.1016/j.cois.2018.06.001.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Lahr, E.C., Dunn, R.R., and Frank, S.D. (2018) Getting ahead of the curve: cities as surrogates for global change. Proceedings of the Royal Society B, 285: 20180643. http://dx.doi.org/10.1098/rspb.2018.0643.

Progress 09/01/16 to 08/31/17

Outputs
Target Audience:We have reached other scientists through peer-reviewed publications and scientific presentations and national meetings and universities. WE reached extension professionals with extension educational resources and presentations. We have also reached stakeholders such as urban foresters, arborists, and landscapers with extension presentations. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Training of graduate students, postdocs, undergraduates, and stakeholders. How have the results been disseminated to communities of interest?Results have been diseminated to stakeholders including urban foresters, landscapers, and arborists via extension presentations, industry publications, and extension resources such as fact sheets and websites. What do you plan to do during the next reporting period to accomplish the goals?Continue conducting experiments in all three objectives as described in the proposal. The watering experiment is about to begin for the summer. We have already collected scale insect data from all the trees. We will continue collecting data on different tree species to establish impervious surface thresholds.

Impacts
What was accomplished under these goals? Objective 1: We have begun establishing study sites and quantifying diversity around trees. Objective 2. The experiment was implemented last summer with all the sites selected in each of the three cities. Three trees were selected at each site and randomly assigned as either the unwatered, watered once per week, or watered twice per week treatments. Scale insect and tree data were collected. Research has begun for this summer with watering treatments to start in June. Objective 3. We began developing impervious surface thresholds for the southern region for red maples and colected data on 6 other tree species to begin calculating thresholds.

Publications

• Type: Journal Articles Status: Under Review Year Published: 2018 Citation: Just, M., Frank, S.D., Dale, A.G. Impervious surface thresholds for urban tree site selection. Urban Forestry Urban Greening