Be careful planning to sustain yourself solely from the land; if you don't know what you're doing, it's a quick way to end up dead. Consult some local experts on the subject if you can, spend time at the local library reading up on the subject. And know in some areas it just isn't practical or possible to do so. Staying hydrated is another huge concern where you will be. Do you have plan on what to do if you get sick?
Don't take me wrong; I'm not trying to discourage you; I just wouldn't want someone wandering off and dying due to a lack of knowledge. How well you plan and prepare will largely determine how successful you will be.