craftgrrl | text-only post: newbie question about spinning wool

I'm learning to spin wool into yarn, but before I actually start, I should clean the roving, right? I'm going by the cleaning instructions in Lee Raven's book Spin It, and she mentions the phrases "shorn ends" and "tips". Which is which? I want to make sure before I wash the wool, because Raven says that you can agitate the tips all you want, but if you mess around with the shorn ends it'll felt, and of course I don't want that. So which end is which? Thanks so much!