This study considers the problem of estimating merchantable volume to some specified top diameter or height limit. The models were separated into two categories. Volume ratio models give the ratios of merchantable to total volume. Taper equations when integrated provide volume estimates of any segment of the bole. Data from plantations and natural stands of loblolly pine were used to compare the models for ability to predict merchantable volumes. Additional evaluations were made among the taper equations to determine the one that "best" describes stem taper. Results showed that different models should be used for different objectives.