I agree with Dobie, photos could help. My experience with feather pecking is very limited, just haven't seen much at all. What little I've seen has not been the large wing or tail feathers, but the small feathers on the neck or maybe the vent area. I don't have the decorative breeds with the strange feathering and I also have lots of room, either of these may affect that. I'd be interested if those that have seen feather pecking see them taking off those larger feathers. We all see different things.
would it do any good to separate her so she has a chance to heal or would that just cause more problems
It sounds like she is not injured, just missing feathers. If the entire feather is gone they should grow back before too long. If even a bit of the shaft is left in there that feather will not grow back until she molts. So if you mean grow her feathers back when you say heal, she might or might not before the molt.
It is suspicious that she is the lowest ranking. Is she the only one missing feathers? Have you seen others pulling her feathers? In situations like this I'm more inclined to isolate the aggressor than the victim, but sometimes the victim is the problem.
I try to solve these things for the safety and peace of the flock instead of only one flock member. If you remove the aggressor and the victim is still a victim, then the victim might be the problem. If you remove the victim and the problem continues then the aggressor is the problem. It's not always easy to figure out.
If you remove the victim for a while and then put her back, it can be like she is starting integration. If you take the aggressor out for a while, she has to work her way back into the pecking order. That may keep her busy enough that she stops that behavior. I have changed behaviors by isolating chickens before, sometimes the aggressor sometimes the victim. Sometimes it works, sometimes it doesn't. Probably worth a try, and I'd start with the aggressor if you can identify one.
All this is assuming that feather picking is your problem.
