Descriptive statistics of tree crown condition in the Southern United States and impacts on data analysis and interpretation
The U.S. Department of Agriculture Forest Service, Forest Inventory and Analysis Program (FIA) utilizes visual assessments of tree crown condition to monitor changes and trends in forest health. This report describes and discusses distributions of three FIA crown condition indicators (crown density, crown dieback, and foliage transparency) for trees in the Southern United States. Descriptive statistics are presented for all trees combined, by hardwood and softwood species groups, and for 53 individual species. Implications of these characteristics and other factors for the analysis of the phase 3 crown condition indicators are discussed.