We investigate how to colour edges of graph so that any two colours make upa spanning tree. This problem is equivalent to transforming the cycle code ofa graph into a Maximum Distance Separable (MDS) array code. Adopting thisgraph-theoretical interpretation allows us to provide a compact description of somefamilies of low density MDS array codes in terms of cycle codes of coloured graphs.This includes a short description of Xu et al.’s “B-code”, together with its erasureand error decoding algorithms. We also give a partial answer to Xu et al.’s questionabout efficient error decoding for the dual B-code. We give alternative families ofMDS array cycle codes, and in passing prove that an optimal MDS array cycle codeof minimum column distance 4 is given by an appropriate colouring of the Petersengraph. We introduce double array colourings which allow the decoding of columnor row errors and provides a new interesting graph theoretical problem. We giveinfinite families of graphs which admit double array colourings.