Guest post by former LUFA student Kaitlyn Pike. Kaitlyn graduated from DePaul in June 2020 with her M.S. in Environmental Science and is currently working on her Ph.D. in Forestry at the University of British Columbia in Vancouver.
In December, my first peer-reviewed paper, “Tree preservation during construction: An evaluation of a comprehensive municipal ordinance,” was accepted for publication in the journal Urban Forestry & Urban Greening. My paper, which evaluated the effectiveness of a tree preservation ordinance in the City of Highland Park, was my thesis research that I completed during my time in DePaul’s M.S. in Environmental Science program.
As we know, mature trees provide us with a plethora of benefits – from carbon sequestration and stormwater management, to improvements to our mental and physical health (Roy et al., 2012). As urban populations continue to rise, however, protecting mature trees has proven to be a challenge for towns and cities that wish to maintain or increase their tree cover. This is particularly important, as studies continue to find that unrestricted construction can negatively impact the condition and survival of trees (Koeser et al., 2013; Morgenroth et al., 2017; Guo et al., 2018, 2019). While tree preservation ordinances (i.e. rules and regulations that protect trees during construction projects) are becoming more common for public trees on public property, it is less common that these types of ordinances exist for private trees on private properties.
Highland Park, IL, a city with a robust and well-funded forestry department, has had a tree preservation in place for the past few decades. Having already worked with Highland Park’s City Forester, Dr. Keith O’Herrin, on another project during my B.A. in Environmental Studies, working with the City to evaluate their tree preservation ordinance for my M.S. was a great opportunity to gain further experience designing and implementing a research project that aimed to solve a real-world problem. Working with Highland Park’s Forestry Section not only gave me invaluable experience into how forestry departments operate, but allowed me to utilize municipal and public records in order to evaluate the effectiveness of the City’s tree preservation ordinance.
The results of my research found that the City of Highland Park is successfully protecting the trees on properties that undergo residential redevelopment – where existing, older homes were demolished and replaced with newer homes. This was evident through 1) a satisfactory tree preservation rate (calculated by using construction site maps to determine which trees were removed after construction occurred vs. which still remained), 2) having found no correlation between tree condition or survival and a tree’s distance from a newly built home (contrary to what previous studies had found where no ordinance was in place), and 3) having found that the soil within the critical root zones of trees was successfully maintained (by not surpassing the literature-recommended compaction level for healthy root growth). Furthermore, my research found that areas where construction activities occurred freely had more compacted soils, while areas where construction was restricted (within the critical root zones of trees) had less compacted soils. This is one of the first studies that demonstrates how tree preservation ordinances can successfully protect trees and soils on properties that undergo construction.
If you’re interested in reading my paper, you can find it here. I was also able to share my results as a poster at the 2020 International Society of Arboriculture Annual Conference, which can be viewed here (or click on the poster below). Please don’t hesitate to reach out to me regarding my research, or if you have any questions about my experiences in LUFA or DePaul’s M.S. in Environmental Science program: firstname.lastname@example.org
Guo, T., Morgenroth, J., & Conway, T. (2018). Redeveloping the urban forest: The effect of redevelopment and property-scale variables on tree removal and retention. Urban Forestry and Urban Greening. https://doi.org/10.1016/j.ufug.2018.08.012
Guo, T., Morgenroth, J., Conway, T., & Xu, C. (2019). City-wide canopy cover decline due to residential property redevelopment in Christchurch, New Zealand. Science of the Total Environment. https://doi.org/10.1016/j.scitotenv.2019.05.122
Koeser, A., Hauer, R., Norris, K., & Krouse, R. (2013). Factors influencing long-term street tree survival in Milwaukee, WI, USA. Urban Forestry and Urban Greening. https://doi.org/10.1016/j.ufug.2013.05.006
Morgenroth, J., O’Neil-Dunne, J., & Apiolaza, L. A. (2017). Redevelopment and the urban forest: A study of tree removal and retention during demolition activities. Applied Geography. https://doi.org/10.1016/j.apgeog.2017.02.011
Roy, S., Byrne, J., & Pickering, C. (2012). A systematic quantitative review of urban tree benefits, costs, and assessment methods across cities in different climatic zones. In Urban Forestry and Urban Greening (Vol. 11, Issue 4, pp. 351–363). https://doi.org/10.1016/j.ufug.2012.06.006
Jess Vogt, Associate Professor, Env. Science & Studies, DePaul University