Tree growth modeling to improve tree size and canopy coverage predictions — Emerging Issues Along Urban-Rural Interfaces:
Municipalities use ordinances and zoning to ensure that tree canopy cover is replenished during land development. Many localities have refined their regulations to enforce their long-term canopy cover goals, requiring developers to plant trees to provide minimum canopy cover for the project site within a specified period of 15 to 30 years. To fulfill site plan requirements, developers specify tree planting densities based on anticipated canopy growth during the attainment period. However, these calculations are typically based on observations of trees growing in non-limiting environments such as nurseries and arboreta, which are not representative of typical urban conditions. Urban conditions are oftentimes very heterogeneous due to the great degree of disturbance providing various soil conditions ranging from adequate to unacceptable. Hence, tree size predictions cannot be generalized for all planting sites and designs and have to be based on research resulting in models that include the factors that significantly influence tree growth.