An alternative method for estimating crown characteristics of urban trees using digital photographsThis article is part of a larger document. View the larger document here.
The USDA Forest Service Forest Inventory and Analysis (FIA) program has concluded that statewide urban forest inventories are feasible based on a series of pilot studies initiated in 2001. However, much of the tree crown data collected during inventories are based on visual inspection and therefore highly subjective. In order to objectively determine the crown characteristics of urban trees and assure reliability of the data, researchers with the U.S. Forest Service Southern Research Station have developed a computer software tool called UrbanCrowns that can potentially be used to assist with crown data collection on urban FIA plots. In addition to its operational use, the software can also be used as a training tool. UrbanCrowns analyzes a single, side-view digital photograph of an urban tree and computes crown measurements similar to those collected during FIA inventories. UrbanCrowns output includes estimates of crown height, live crown ratio, crown diameter, crown density, transparency, and crown volume.