EVALUATION OF SPATIAL APPROACHES AND EQUATION FORMS USED TO PREDICT TREE CROWN RECESSION

Abstract

This study was carried out in Zakho area on stand Populus nigra. Different types of measurements had been taken for the area, measurement cover number of trees of hectare for each stand. Sixty Random samples which area of (0.01) ha. By using different regression in statgraph system to derive mathematical equations for this information. We prepared the relation between heights of base crown, crown ratio as depended variable of trees and stand as in depended variable, the obtained results were: )0.00295A -xp e -HIW = 2.7159 + 19.0536 * Hm (1 = 0.70 SE =0.998 2R 0.1767 HIW ) -( 0.1335 +0.1559 Hm exp -CR = = 0.89 SE = 0.1734 2R The coefficient of determination and standard error of equations gave good value, these equations had been modified in two tables (2 and 3). We can use these tables by manager to reach the object, to produce the maximum yield of stand, and for this table we can determine crown ratio at different age and density.