Speaking from someone who has suffered through the clouds of mosquitoes and blackflies you get in the canadian north, I can't really tell (clean versus not) - I think really clean I get eaten alive, but after a bit of deet, and a bit of woodsmoke I find I do much better. if I'm in blackfly country in june/july I will actually make a bit of a smoke smudge with green black spruce boughs and take a "smoke bath" - it's not like being dirty, but the smoke seasons you up a bit and keeps some of 'em off. well, that and DEET.

I find once they are really really bad the biggest thing I want is a headnet - I can keep 'em from biting me with deet and smoke and clothing, but I still have to breathe, and when it's bad up here they will literally drive you crazy even without biting they are so thick.

I *always* have a small headnet in my ditty bag. it weighs nothing and when I need it I *really* need it.