In JZ book many recipes call for Hallertau hop. Just Hallertau. But which one is that? In my LHBS there is Hersbrucker, Spalt Select, Mittelfruh, just like here:
in morebeer I see something called just Hallertau, is it a different sort of hop?
HomeBrewTalk Wiki has some great information on the Hallertau hop growing region of Germany and the many different cultivars developed and grown there.Category:Hallertau and Hallertauer hop varieties - Home Brewing Wiki
I have hops labeled Hallertau. I don't know which they are but I am guessing they are Hersbrucker or Tradition. Wish I knew.
I don't claim to know anything about the different varieties. As long as you know the AA%, you should be fine with any.
OK, I've found a podcast, where Jamil Z explains, what he means by Hallertau - basically it is Mittelfruh, bu, since it is so hard to buy, we can use any Hallertau variety which comes handy.