A specific analysis of the alpha inherited Crystal Orientation Map (COM) is proposed to study the beta-->alpha texture inheritance of a Zy-4 rod. In particular, it is shown that the alpha colonies inherited from each parent grain can systematically be identified on the alpha Map by considering the misorientations between pixels. Once identified, the orientations of these colonies are used to calculate the orientation of their common beta grain. Finally, the orientation data of the parent phase can also be displayed as a COM. The beta COM shows that at high temperature, the beta grains were mainly oriented around the <111>//AD fibre. Moreover, the analysis of the parent and the inherited COM, makes clear that each beta grain has preferentially transformed into different variants belonging each to the <11.0>//AD fibre. This variant selection is responsible for the sharp alpha texture of the Zy-4 rod after a treatment in the beta field.