Relationships between morphological characters of Brant's oak (Quercus brantii Lindl.) trees with acorn crops in Baneh Forests

Estimation of acorn crops has special importance due to the role of acorns in oak forest silviculture and wildlife management. There are no adequate researches about acorn production of Iranian oaks because direct measurements of acorn production are difficult. Regarding to vast distribution area of oaks in forests of Iran especially in Zagros Forests، this research was carried out in Halou village of Baneh، Kurdistan Province، in 2010. We tried to calculate the best regression model for estimating acorn crop of Quercus brantii by the aid of morphological quantitative characters of tree. At first، 100 sample trees were selected using stratified random sampling. Diameter at breast height، collar diameter، total height، crown length and small and big diameter of crown were measured on sample trees، then their acorn crops was measured by crown counting method. Four simple regression models were used to determine the relationships between acorn crops and quantitative characters including Linear، Quadratic، Power and Exponential. The highest significant correlation was found between average diameter of crown and acorn crop (P < 0. 001; R2=0. 6). The results of this research confirmed the effective application of some quantitative characters for predicting acorn production in Q. brantii.