Digital photography for urban street tree crown conditions

Abstract

Crown variables such as height, diameter, live crown ratio, dieback, transparency, and density are all collected as part of the overall crown assessment (USDA 2004). Transparency and density are related to the amount of foliage and thus the photosynthetic potential of the tree. These measurements are both currently based on visual estimates and have been shown to be highly variable between observers (Solberg and Strand 1999). Additionally, the collection methods for these variables are not controlled for repeated measures analysis. Digital image capture using relatively inexpensive digital cameras from monumented (using tree as reference) locations is proposed to enable more sensitive analysis of trends in these variables over time by eliminating observer and viewpoint effects. The additional information of crown profiles and spatial distribution of foliage may also provide useful information for modeling.

Citation

Clark, Neil A.; Lee, Sang-Mook; Bechtold, William A.; Reams, Gregory A. 2006. Digital photography for urban street tree crown conditions. Proceedings, Society of American Foresters 2005 National Convention. 4 pp.