Well tried to put 4 ready to lay isabrowns from hatchery in with rest of flock mixed flock mostly EE. Browns were 19 weeks and most of the others were ~16 weeks some under. I set them out together in fenced area, all seemed good, couple evil eye moments but nothing, so let them coup together, day one was fine, then day two all four browns just got plain nasty and were going out of their way to pick on the others constantly. Least the browns were beak trimmed else there would have been blood for sure. So pulled them back out and they get the smaller side of the coup. I guess it is for the good, can feed them layer ration as they are popping out a few small eggs and keep the others on grower for a while longer. What a difference though from the EEs that came from free range flock to the browns from hatchery. Browns don't have much for brains, little personality and are just butt heads, not jumping up to the roost not catching onto what a nesting box is for. Surprising though they are not bad to handle. I wonder, when the EEs catch up and start laying will it be worth trying to put them back together?