I've had multiple guerrilla grows from start to finish, this one of which I got ripped. I spent the winter months exploring, found a huge patch of nasty thick bushes a few hundred feet wide out in the woods. And I basically just crawled through way into the middle, where there were no large trees to block the sunlight, and cleared out a patch (about 20' by 20' wide) of the bushes. I set up my grow there. Everything went great, I took about 3/4 of my plants down late october and left the rest because they needed more time. But I suspect that at some point or another someone followed me or saw me hiking out into the forest off the trails, because I went back to harvest the rest and they were gone. I realize after that I had been walking the same exact route everytime and and had probably started to make a little bit of a trail that someone easily followed.
Anyway, DO NOT leave any kind of trail. Since that grow I have tried to take a different route to my outdoor grows EVERY SINGLE TIME I visit my plants, and haven't been ripped again. Do not let anyone see you wandering into the forest EVER. It could be a five year old or someone's grandmother, doesn't matter, abandon your plan, turn around, whatever, but just make sure no one is ever around to see you heading to your spot. You have to be a ninja if you grow guerilla style. Don't leave anything bright colored (like soil bags) in plain view for the choppers. And of course don't tell anyone about your plants, but I'm sure you already know that.
Be smart, take precautions, and you can grow guerilla style successfully.
Good luck dangerousknowledge,
-Norcal Grower