The tree represents Amir and Hassan's relationship, which grows and blossoms at first, then which, over time, goes sour because of Amir's condescending attitude, his jealousy, and finally his betrayal. Early on, Amir and Hassan would meet at the tree to play or simply to be together. When Amir snubs Hassan, however, Hassan takes some of the rotting fruit and smears it into his skin out of sheer exasperation and self-disgust. (Some critics see this also as a symbol of self-sacrifice.) The staining of his own skin represents the stigma Hassan must bear by being born of inferiour status - meaning his ethnic identity and role as a servant's child via his mother (and though unknown to him, by his illigitimacy via his father).
The red juice from the pomegranate could also represent the violence Hassan will meet later on in life. When Amir learns through a friend about Hassan's true relationship to him (he was his half-brother), it is too late to restore their relationship. However, Amir makes up for his past mistakes by saving Hassan's son and even adopting him as his own child.
As an extended symbol, the pomegranate tree could also represent hope and new life. If the "firstfruits" of the boys' relationship have indeed been lost, healing, love and finally joy come again through Amir's loyalty to Sohrab, Hassan's son.
very well worded answer by parkerlee i must say(:
i agree completely
I also agree completely! Great job parkkerlee! Kudos! :)