I built an A-frame tractor about 7' x 4' (that was the length of the scrap 2x2 I had) so about 28 square feet at the base, planning on two hens. (To tell the truth its not entirely done yet). Having two chicks that are about old enough to move in, I'm wondering how many more I could fit. Seems like one more would be OK (still almost 10 sq ft. each), but I'm imagining beyond that might start causing issues, especially if I don't want to be moving the tractor all the time. Any thoughts, oh wise backyardigans?