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A volume and taper prediction system based on d10 and consisting of a total volume equation, two volume ratio equations (one for diameter limits, the other for height limits), and a taper equation was developed for bald cypress using sample tree data collected in Louisiana. Normal diameter (dn), a subjective variable-height measure applied to bald cypress (Taxodiumdistichum (L.) Rich.) in place of diameter at breast height (dbh), was found to be inferior to five different fixed-height diameter measurement points in terms of predicting total volume. Diameter measured at 10 ft (3.0 m) above the ground, termed d10 is recommended as a better diameter measurement point for bald cypress. A number of "goodness-of-fit" statistics were employed to evaluate alternative functions for predicting volume and taper. Two statistics, bias and sum of squared relative residuals, provided the best discrimination between functions.

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Data from 200 plots randomly selected from the Southwide Pine Seed Source Study of loblolly pine (Pinus taeda L.) were used to fit whole-stand and individual-tree equations. Another 100 plots, also randomly selected, were used for validation. Outputs from the individual-tree model were then adjusted to match observed stand attributes (number of trees, basal area, and volume per hectare) by four disaggregation methods: proportional yield, proportional growth, constrained least squares, and coefficient adjustment. The first three are existing methods, and the fourth is new. The four methods produced similar results, and the coefficient adjustment was then selected as the method to disaggregate predicted stand growth among trees in the tree list. Results showed that, compared to the unadjusted individual tree model, the adjusted tree model performed much better in predicting stand attributes, while providing comparable predictions of tree diameter, height, and survival probability. The proposed approach showed promise in the ongoing effort to link growth models having different resolutions.

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Remeasurement height data used in this study were collected from plantations of loblolly pine (Pinustaeda L.) established in the Southwide Pine Seed Source Study. Three different methods for estimating coefficients of five base-age-invariant site index models were evaluated. The first method involves obtaining coefficients from either a height–age equation or a differential equation. Coefficients from the remaining two methods were estimated from a height growth equation (difference equation) of which the dependent variable is either stand height or logarithm of height. Statistics used in the evaluation were mean of the differences (between the observed and predicted stand heights), mean of the absolute differences, and square root of mean squared error. Results indicated that in most cases, coefficients of the site index models evaluated should be obtained from the height growth equation.