A Basal Area Ratio Predictor of Loblolly Pine Plantation Mortality

Abstract

Abstract A predictor of the probability of plantation-grown loblolly pine ( Pinus taeda L.) periodic mortality is presented. The dependent mortality variable, Proportional Stem Mortality (PSM), is the proportion of trees in a level of the predictor variable, Basal Area Index (BAI), which died over a specified period of time. Basal Area Index is the ratio of the basal area of an individual tree on a sample plot to the basal area of the tree of mean dbh on the sample plot. Data for the predictor is obtainable from any sampling scheme which results in a list of diameters for each sample plot or point. The predictor was developed and evaluated using data from a nitrogen fertilization study where mortality over a 3-year period had been observed. Weibull functions were fitted to the PSM-BAI data using an iterative hill-climbing technique called pattern search. Forest Sci. 25:275-282.