Water usage by Poplars

[av08 at dial.pipex.co.za]

Question concerning water usage of Poplars.

    Assumptions:
     One hectare of Poplar deltoides
     600 stems per hectare
     soils suitable for maximum growth
     
Assuming that there is ZERO rainfall; what would be the water requirements 
(millimetres per hectare) at age 3, 10 and 15 years to achieve maximum 
growth.
Being a deciduous specie the growing season would be for a 6 month period.

Hope there is someone that can give me an answer.

Harold