I found this -

[Granny smith apple trees are not self-pollinating. This means that another type of apple tree is needed in order for the granny smith apple tree to produce fruit. Like most other apple trees, the pollinating tree used with a granny smith does not really matter that much. As long as the pollen is fertile, nearly any apple tree will be able to pollinate a granny smith apple tree and create delicious fruit.

Granny smith apple trees are hardy in zones six through eight, and require a good deal of sunlight. When pruned and cared for properly, a granny smith apple tree will grow for over fifty years. Granny smith apple trees do not require very much support, as they are typically able to support their own weight. In the semi-dwarf state, granny smith apple trees will grow to fourteen feet high.]
http://www.aboutappletrees.com/grann...ple_tree.shtml

doesn't say if bees are really needed or not tho