It used to always bother me in FO3 that the wasteland wasn't green. After all, there's no way the remaining food would support any human life if there weren't still crops. So if I'm there, plant life must still exist and so the wasteland should be green. Also I've seen reports on Chernobyl (as well as Hiroshima and Nagasaki). THEY are green even after heavy radiation.
Here we are in Fallout 4 and there ARE crops but how did they survive unless there is plant life (and there is limitedly). The trees would have survived and the grass would have too -- not everywhere but it would have come back everywhere. I don't think it's necessary to the atmospherics for the surrounding land to be bleak -- after all the situation is bleak enough. Not a big deal but I think I would like it better if I believed human life could be supported on the wildlife and plant life still around.