Mart,
Again I agree that most of the year, foraging all your food is quite difficult. There are a few important autumn crops, specifically acorns and apples are the ones I have found, that give enough calories and nourishment to sustain a person, but one needs to drop everything and go harvest them if they want enough, especially if they are far away. I live in a part of the valley where neither are abundant, so it is a bit of a journey to get to the right groves. Unfortunately, last fall I was not in a state which allowed extensive picking of either, but I got some acorns nevertheless and was able to have a week or two with acorns as a staple. There were also some blunders by others which lead to the remainder of my harvest being wasted because it was placed somewhere chipmunks could get to (and I didn’t know where they were until it was too late), which was a horrible feeling.
If everyone is onboard with the harvest, it is likely to turn out better than it did for me. One also needs to drop most things and focus on gathering such staples for a certain time frame, like the harvest of wild rice in other parts of the continent—having healthy, nourishing food for the year is the most important task. Acorns have mast years and so it is a good idea to save more than you need for one year, as not every year will grant a sizeable harvest. But fortunately they can be stored dry for a while.
I’m planting more oak trees—it may not help in this crisis, but it’s always good to sustain what sustains you.