Estimating breast height diameter and volume from stump diameter for three economically important species in Turkey

Predicting volume directly from stump dimensions is useful in many situations, such as timber trespass. In the present study, equations for predicting diameter at breast height (dbh) and tree volume from stump diameter outside bark were developed for three economically important tree species in the forest region of Bucak, Turkey. Diameter at breast height was estimated with relatively high accuracy using a simple linear model. Tree volume was estimated with high precision using an exponential equation. Weighted linear and non-linear least squares methods were used to consider heteroscedasticity observed in the volume-stump diameter relationships. The results of a non-linear extra sum of squares method and of the F test indicated that different equations are needed for estimating dbh and tree volume from stump diameter outside bark for different species.