Survival Sugar?

I'm thinking about trying Maple surgar/syrup making. I have a lot of Maple trees on the property. I have been reading a book written by Scott and Helen Nearing (noted socialists/communists). They moved to a rural farm in the 30's and made a partial living by making Maple syrup and sugar. I know nothing about doing it so it will be a great experiment. When the SHTF then syrup/sugar will be a welcome barter product. Not to mention for your own use.