I have 15 year old barberry shrubs running along my apartment building wall. Several started dying a couple of years ago and now there are empty spots. I looked at all the big nurseries here in Chicago and they only carry the more popular varieties right now. Researching the internet, I think my shrub is the Emerald Carousel Barberry. It has the exact same leaves, size,flowers, and berries. The only thing that's different is that my shrubs turn a little rusty color in the fall, not the bright red/ purple that describes the Emerald. Are my shrubs another variety or can the ph in the soil create the difference in the fall colors? Anyone's help and advice would be greatly appreciated.