Volume models for Tectona grandis (Linn F.) in Mbavaa Forest Reserve, Benue State, Nigeria

Abstract

Tectona grandis (Teak) is a fast-growing exotic tree species utilised for numerous purpose such as pole and furniture making and it is one of the most preferred species for investment opportunities, due to its high wood quality and excellent growth performance. Effective management of Teak plantation requires information on volume of the growing stock of the plantation. In spite of the importance of volume models, accurate and site-specific models is not available for the study area. The objective of the study was to develop equations which best predict individual-tree volume that will evaluate and estimate the yield of Tectona grandis trees in Mbavaa Forest Reserve, Konshisha Local Government Area of Benue State. Simple random sampling was used in selecting sample plots. Temporary sample plots of size 20m x 20m resulting in Ten (10) plots was laid. Thirteen volume models which consisted of the simple linear regression models, multiple linear regression models and logarithmic transformed models were used for tree volume estimation. Diameter at breast height values ranged from between 25cm to 32cm. The logarithmic combined variable equation of diameter and height (equation 11) had more precision in the estimate, as displayed by the values of coefficient of determination, standard error of estimate and root mean square error) it was therefore selected as the best model for volume estimation for the study area. Precaution should be taking when applying the equation in other locations with similar site condition.