It is necessary to consider the heterogeneity of rainfall interception (I) since it controls the water input to a forest plantation. The rainfall partitioning occurring in plantation forest ecosystems of the semiarid climate zone is suffering from insufficient information; especially information from individual tree measurements. We measured I of individual trees of Pinus eldarica afforested in the Chitgar Forest Park, near Tehran, Iran. To measure throughfall (TF), 20 rain-gauges were installed beneath the crown of the five individual trees. The cumulative mean values of relative percentage of I (I:GR) for P. eldarica trees averaged 44.2%. Significant negative relationships were observed between percent of I:GR and GR for P. eldarica (R2 = 0.63) trees. Understanding the interaction between canopy characteristics and I thus is essential for quantitative modeling of the effects of forest plantations on water budgets
