1. A method for retrieving data from a dispersed storage network comprising: processing a request to reconstruct a data segment at a processing module, in which the data segment is dispersed error encoded to produce a plurality of data slices and in which at least one data slice of the plurality of data slices is further dispersed error encoded to produce a respective plurality of data sub-slices, wherein the data slices and the data sub-slices are stored in a plurality of dispersed storage units; identifying locations of the data slices and data sub-slices stored in the plurality of dispersed storage units; and retrieving a first threshold number of the data slices to reconstruct the data segment and when retrieving a particular data slice, the particular data slice is further sub-sliced, the particular data slice is reconstructed by retrieving a second threshold number of respective data sub-slices corresponding to the particular data slice to reconstruct the particular data slice.