1) I don't know if there's an answer that fits the criteria, but character is going to need to make a dugout canoe a long way from home (or anything really) and I assume this will need to be sealed. He is prepared to do this in advance, but he can't carry anything too heavy (as he has to carry that and a child on a long walk). He can use something in his natural environment but he only knows it second hand, from books and the like.
So either something that can be spread thinly so he could fit in a medium sized flask or that he can find and extract easily.
Or would a canoe survive a several hour long trip without being sealed?
2) He needs to bleach his son's hair. Lemon juice is not an option (and I suspect it wouldn't be strong enough). I have a feeling that urine would work but I'd like to avoid it if at all possible. Ideas?
(I've tried googling both, but they either bring up answers involving modern equipment or for (1) don't mention sealing unless I google it specifically, in which case it takes it to mean seal hunting)