Panel Paper: Resident Requests and Expert Evaluations: Spatial Analysis of the Squeaky Wheel Phenomena in Compounding Urban Tree Canopy Disparity

Friday, November 8, 2019
Plaza Building: Lobby Level, Director's Row I (Sheraton Denver Downtown)

*Names in bold indicate Presenter

Sally Geislar, University of South Florida and Emily Huff, Michigan State University


The benefits that trees provide urban areas range from improved air quality and increased energy efficiency to recreational opportunities and positive emotional effects (Dwyer et al., 1992; Kuo, 2003). Despite the many benefits provided by a healthy urban tree canopy, there are millions of municipally-owned trees that pose hazards or create a nuisance for residents. Unfortunately, many cities have insufficient resources to maintain these trees and often rely on multiple sources of information to prioritize tree maintenance, such as professional arborist inventories and resident requests for maintenance. However, potential mismatch between residents' perceived tree care needs and needs determined by professional arborists may create or contribute to tensions between residents and their municipality.

In many American cities, urban forestry maintenance priorities are established via citizen requests for tree work (e.g., phone calls, on-line tickets). If citizen requests do not accurately represent the work needed across the population of municipal trees, or requests are received in an unbalanced manner, prioritization of maintenance may not be ecologically sound or may over-represent neighborhoods.

While previous research has shown that there are often disparities in existing urban tree cover and quality by race, income, and owner-status, this is the first study to investigate disparities in resident requests for maintenance and city inventory priorities. Landry et al. (2009) found that low income, predominantly African American neighborhoods may have less tree cover or trees of poor quality. Further evidence suggests tree planting initiatives are not equitable, but rather favor neighborhoods with a lower concentration of poor and non-white residents (Watkins et al., 2016). A better understanding of the relationship between neighborhood socioeconomic factors and the perceived needs by experts and residents is needed to ensure that urban canopy disparities are not compounded at the stage of prioritizing tree maintenance.

We test three hypotheses using data from professional inventory of tree maintenance needs, resident tree maintenance requests, and socioeconomic variables in Grand Rapids, Michigan. First, we expect that resident requests for tree maintenance do not correlate with the condition of trees based on the city's professional arborists' evaluation of maintenance needs. Second, we hypothesize that census blocks with residents of higher socioeconomic status are more likely to request tree work. Finally, we expect census blocks with residents with lower socioeconomic status are more likely to have trees in poor condition.

We will conduct spatial analysis to test these hypotheses. Specifically we will analyze the spatial point patterns of inventory and requests using Pairwise Correlation Function. We also analyze the relationship between spatial position and non-spatial value of each data point (e.g., tree quality) using Geographically Weighted Regression. Results will demonstrate whether expert evaluations and resident requests are related.

This research contributes to the ability of municipalities to visualize and quantify their tree maintenance needs and to compare expert evaluations with resident requests. This research also demonstrates a research method that helps prioritize city resources and builds trust within possibly disenfranchised neighborhoods.