Clarity

Another one of those questions that needs to be answered sometimes. What I call a swede is Brassica napus napobrassica. It's round, brownish, and very heavy. (And gets kitchen knives stuck in it.) You dice it and cook it and mash it with butter and pepper and it comes out a lovely orange yellow and is sweet. What I call a turnip is Brassica rapa rapa. Also round, but smaller, and white to purple on the outside.

But.

It emerges that some people call my turnip a turnip and call my swede a rutabaga. Other people call my turnip a white turnip and call my swede a turnip. (I haven't seen Blackadder in a while, but I think they do that there.) And lots of people think that whatever it's called, it's cattle feed.

Which is which??!!!