I will admit to not having enough time to do much gardening; my reasoning for planting food trees was based on this. It does mean that I am subject to the vagaries of the weather - if things are too dry for too long right after planting trees, it's easy to lose them.
Case in point, I had planted four willow trees right before a dry spell - they survived some time, but then died off. I tried to find replacements - having a source of aspirin PSHTF is reasonably important; however, it is an invasive group of plants, spreading very easily. After thinking for several weeks that I should remove the remnants, I looked closely and found that at least one is not just growing, but thriving. A single tree is all that's needed; four was a useful number, but willow will readily grow from cuttings, so one will give many, many more.
On a similar note, I found that a native plum seedling, that I had regarded as dead many months ago, has send out new leaves.
Life will find a way....
On another note, the drums of war sound yet again, banged on by those who see merit only in destruction...