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On-line Proceedings of the
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Efforts to restore Atlantic White Cedar (Chamaecyparis thyoides L.) over parts of its historical range have led to an increased interest in the species for commercial logging. With this interest comes the need to develop equations to estimate the taper and volume of Atlantic White Cedar (AWC) stems. A total of 210 stems were selected from three different regions of North Carolina for the development of taper and volume models. Diameters at approximately 5 foot height intervals were measured from each selected tree. Several previously developed taper models were tested for their fit to this data using mixed modeling techniques. Of these examined candidate models the Demaerschalk (1972) model had the best fit, though a common trend was noted in the residuals of several of the candidate models. A new taper model, termed LES, was derived in order to account for this common trend in the residuals and achieved an improved fit to the Atlantic White Cedar diameter data. Though significant differences between the three measured AWC regions of North Carolina were identified by the LES taper model at an alpha level of 0.05, these differences did not translate into any practical differences. Integration of the taper model created an associated volume model for AWC. Calculated volumes estimated from this new volume model were compared to total stem volume values calculated with Smalian's volume equation. The new volume model had an R2 of 0.9883 when regressed to the Smalian volumes. The models presented in this research should help land managers more accurately assess their AWC stands.