Prognostic Crown Diameter equations for a Mixed Species Plantation in Southern Nigeria

The dimension of a tree crown has an apparent effect on and is strongly linked with the growth of the tree and its diverse parts. Crown information is an important part of numerous growth and yield models. Hence, empirical predictive equations for the crown diameter of a mixed species plantation in Southern Nigeria were developed and evaluated in this study. In studying this phenomenon, total enumeration of the selected species in the mixed species plantation was carried out. Moreover, major growth attributes of 185 trees of six species, namely: Khaya ivorensis, Entandrophragma angolense, Terminalia ivorensis, Tectona grandis, Treculia Africana, and Mansonia altissima were measured and estimated using mesurational methods. Descriptive, correlation, regression, and residual analyses were then applied to the quantitative data obtained from the mixed species plantation. For all the species, the best adjudged model, with the best fit indices, was Ln(cd) = Ln(b0) + b1·CPA·dbh, R2 = 0.936, SEE = 0.037; an indication of parsimonious potential of a predictive exponential model. This paper, therefore, revealed the possibilities of predicting the crown diameter for a mixed species plantation in Nigeria with ample prospects for sustainable planning and management decisions that are relevant for any mixed species plantation.