Stars from Fig. 3 in the [Mg/Fe]-[Fe/H] plane. This time the three populations are identified by colour. Blue is the low-α population, red is early high-α and green is late high-α. The grey stars are the buffer zone used to minimize contamination between the low and high-α disks. (The dotted line is a purely visual aid to show the approximate boundary of the two high-α populations.)