I didn't know there were so many different Berberis.

I didn't either.

Dear Lynn, there are a lot of Berberis sp. A lot of people over here use purple and then green ones mixed as a hedge. Don't ask what species as there are far too many of them. They buy them from the hedging adverts in the Sunday newspapers. You can buy conifers and beech etc,. from these nurseries, that advertise. For an ultimate form of plant defence some people put Pyrecantha or firethorn in with them. Try to get through that! Plus the birds love them as firethorn has mass berries as well.
Regards.
Neil.

I have one Pyrecantha. I don't know which one, it is very old, probably planted in the 1950's. The birds love the berries, and when it is in bloom it stays covered with bees of all kinds.