Tree preservation during construction: an evaluation of a comprehensive municipal tree ordinance

Abstract In the United States, urban forests represent 35% of all urban land cover, and deliver benefits to nearly two-thirds of the population. As global urban populations continue to rise, however, redevelopment is continually reported as a major factor in reduced canopy cover. While urban trees provide us with measurable benefits when adequately maintained, their costs when not cared for remains poorly understood. In order to safeguard the benefits that urban forests provide, municipalities have begun to introduce ordinances with the intention to protect and manage trees within their community. The aim of this study was to better understand the condition and survival outcomes of residential trees intended to be preserved through a municipal tree preservation ordinance. The results of this study found that a comprehensive tree preservation ordinance can successfully protect tree and soil health during and after residential development occurs. This is evident through an overall preservation rate of nearly 75%, having found no correlation between proximity to newly developed foundation and observed tree condition or mortality, and the discovery of healthy soil compaction levels within tree protection areas and the critical root zones of preserved trees. Collaborative research as demonstrated by this project can help both academics and professionals gain a better understanding of how to best manage their own urban forests.