Answer:
Amir and Hassan are from unsimilar backgrounds but still they are great friends. They trust their loyalty to each other and that their friendship is a long lasting kind.
Like most young boys they spend their time playing at the field running around and doing what boys do.
Pomegranate trees is at one of the places that they visit as they play around.
They could be playing on a sunny day and these trees will provide them with a shade to sit under as Amir reads to Hassan since he isn't permitted to be at school as a son of a servant.
Amir then come up with stories to tell Hassan, pomegranate tree is a representation of the beauty of their relationship as friends , how they look after this friendship.
Under this tree they have found a special exceptional place where they spend their best times together however it changes After Amir experienced a tragedy with Hassan the meaning of the tree changes .
Amir feels guilty that he wishes thay Hassan can show his anger towards him but Hassan doesn't even respond when he throws him with pomegranate seeds.
When Amir sees the pomegranate again without bearing fruits he sees a representation of how fade away their relationship is now .