10 sq ft/bird for Run even if it is a tractor?

[Avonshire]

So we plan to move our coop every few days. Right now we have 12 birds but they are babies and we will not be keeping the roos so I am not sure how many we will end up with but let us say 10(optimistically thinking!). So our coop is 4'x7' and the run is 8'x7' and there will also be the space under the coop. So the run is more like 12'x7'. However does that give us enough space for 10 birds? Is the 10sq ft/bird if it is a stationary coop/run or does that not factor into the equation?

 

[teach1rusl]

Yeah, tractors seem to work best for small groups of birds, like maybe 4-6...they really weren't intended for larger flocks. And that's mostly due to logistics; a tractor large enough to house bigger numbers of birds quickly becomes too heavy/bulky to move regularly.
That being said, I do think many folks who use tractors don't give the minimum recommendation of 10 sq. ft. per bird. Obviously, those folks have to move the tractor more often to prevent overgrazing, since that's the primary purpose of a tractor. Give it a try and if it's not working, simply further reduce your flock...