Can you mix Carolinan and Italian bees in same area and even in same boxes?
I hope you don’t mind - I edited your title. I have never heard of Carolinan bees, but Carniolans are quite popular, so perhaps you meant those?
You can certainly mix them in the same apiary (in different hives). They are both strains/variants/subspecies of the Apis mellifera species, and it doesn’t cause a problem if you have them in separate hives. If you mix the two variants in the same hive, it is going to depend on how you do it. If they are from different original sources, I would recommend a newspaper merge (Search tool upper right of the screen if you need more info on that), to minimize fighting. Any hive will only tolerate one queen, and within about 9 weeks, the hive will be mostly bees of the strain of that queen. So if you have a Carniolan queen, the bees will eventually all be Carnies. I really don’t see the point of mixing them, unless you are trying to strengthen a weak hive. Hope that answers your question!
Yes I thinking of buying a nuc to go with the package bees and they are different so if I put one frame of the brood in the package hive would they just kill them off as they hatch or would it strengthen the package bees?
Yes I don’t mind the edit. And I was trying to see if I can add brood from the nuc I would buy to the package bees to strengthen them or would they just kill them off? Keeping them in different hive boxes of course keeping the queens in different boxes. I understand it might weaken the nuc but would it strenghten the package bees being of different sub species
You can do that, and the package bees will not kill the brood. Just make sure that the nucleus queen is not on the frame of brood. I would be inclined to shake the nurse bees off the frame before adding it to the package hive, not because they would fight (they probably would not), but because you are already weakening the nucleus by removing a frame of brood, and keeping the nurse bees with the nucleus would help the remaining colony.