Juvenile Height Equations for Plantation-Grown Date Palm (Phoenix Dactylifera L.)

The juvenile height equation was developed forplantation-grown Phoenix dactylifera L. species in Modibbo Adama University of Technology (MAUTECH) Date Palm Plantation. In the four hectare date palm plantation, 15 sample plots of 35 x 35m wererandomly laid in the entire plantation.Ineach of the laid plot, all the standing trees were enumerated, and measurements were carried out on the variable of interest. The collected sampled plots data was divided into two groups for model calibration (70%) and model validation (30%). The measured tree height was fitted as a function of computed Crown Area (CA) and Number of Branch leaves, using stepwise regression method The predictive abilities of the selected juvenile height equation was evaluated, using Coefficient of determination (R2), the bias (Ê) and Standard Error of Estimate (SEE). The results on degree of association between the juvenile tree height, crown area and number of branches revealed a strong positive correlation coefficient. The predicted height models were ranked and screened, and the best equations was chosen based on its high coefficient of determination (R2) value of 75.8%, low SEE value of 0.2398. The result on the residual shows no significant difference between the observed and the predicted data (P> 0.05).which is an indication that the model is of good fit.The result of this study reveals that the height equation generated will serve as a reference to determine the future height equation of the Date palm (Phoenix dactilyfera L.) plantation in any area having similar environmental conditions.