That quality list is more hopes than facts.
The British moved Europen Black bees to every continent where they went. But now no one use that Black Beauty in commercial beekeeping on those continents.
It was most common bee in Finland but varroa killed that race in couple of years when mite arrived to the district.
I nursed 30 years MM crossings. I have nothing good to say about it.
But as far as I know, no one made selective breeding among Blacks. They lived quite succesfully in nature but vanished quickly with the help of varroa.
When that Black Devil vanished, some Finnish beekeepers founded mellifera mellifera society. But too late.
I have not seen that bug during last 24 years.
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