combining the flock

[birdface]

Im getting ready to put my two "flocks" together as soon as i get my new coop finished. I was wondering if theres an easy way to switch up the pecking order. I have 2 groups of 2 that im putting together. One group is about 9 months old and the other is close to 4. I want to put my one, more aggressive chicken at the bottom of the order. I was thining of putting her in my garage brooder box that i have for about a week or so. Its plenty big enough for her.

And how do i keep them from eating each others food since the older ones are eating layer, they all free range all day.

 

[teach1rusl]

If your one group is 4 months old (around 17-18 weeks), then that's old enough to start eating layer feed. But if you're not wanting them to eat it, then you'll have to switch to a flock raiser feed (Puriana sells one, not sure of other brands), because there is not a way to keep them out of one another's feed.
Free ranging is a good way to make integrations easier simply because they have so much space to stay out of one another's way. The challenge comes at roosting time. I take it the lead hen you're talking about is one of the 9 month olds? You could keep her separated, as you mentioned, for about a week while the other three get to know one another. However, with that few number of birds, and with that gap in ages, she will probably still end up on top when she's put back with them. But the lower of the older birds will at least have a chance to "like" the youngsters first. I would make sure that the younsters are able to roost in the evenings (that the older birds are letting them)...at least for the first few days. Another plus is that the coop will be new to all.