Although several urban field protocols use a complex and comprehensive approach to measuring trees that fork between one and 4.5 ft. (30 and 137 cm), our research indicates that many urban forestry practitioners use simpler, less time-intensive methods that, for the genera we measured, show comparable predictive power and may offer greater repeatability for longitudinal monitoring.
2017 Urban Fellow
Research Topic: Land Use Planning and Management
Faculty Advisor: Mark Ashton
Urban Forest Mensuration
Feasible, correct, and useful measurements of urban trees are essential for both research and management, including accurate quantification of urban tree benefits and long-term monitoring. However, the standard forestry measurement of trees—diameter at breast height (DBH), taken at 4.5 ft. (1.37 m)—was developed for very different applications (e.g., timber valuation) and may be unsuited to the specific needs of municipal arborists and researchers, particularly with regard to multi-stemmed trees. We took intensive measurements on 569 trees of three genera (335 multi-stemmed) in Philadelphia and surveyed 25 urban forestry practitioners in 12 cities in the eastern U.S. on the management and measurement of multi-stemmed street trees, to determine which methods for measuring multi-stemmed trees were best suited to the goals of urban forestry researchers and practitioners. Research is ongoing, but preliminary results suggest that researchers and practitioners may be able to simplify existing protocols—thus saving time and reducing the capacity for confusion and error—without losing valuable biometric information.