Jerry, I hear your quandry, I wonder the same exact things. We have chickens, ducks and turkeys. Just try and keep the older birds out of the baby birds feed. When you have communal houses and yards, well.....then there is issues. The ducklings are old enough now that they don't need the starter (I think, from what I read). That is good because the stupid chickens prefer that to their laying pellets.
The turkey poults are still on starter and they only come out of their own tiny teeny yard for a few hours a day and I close their little yard up, they wander the big yards with the mothers. The chickens love to try and sneak in and eat their starter too. It really is quite a time consuming bunch of work to try and keep the chickens away from the baby food. What gives.
You are getting good answers, and I am listening, because I am in the same boat and will be in that boat again when the chickens hatch from the incubator, when they get a little bit older to go out of the brooding pen.
Jerry, just keep reading and listening, you will have to extract the information and figure it out, you will do it.
Are you lovin' to have the chickens around? Sure is a cool experience eh? So glad that you got onboard with it.
Turkey poults are so curious and really not that intelligent, I am finding out all kinds of strange things about them, they are not even remotely like young ducks that don't even stray 10 inches from the others in their clutch (is that what its called). They stick together. Not the turkeys, they are all over the map and I have to rescue one every now and then because I can hear it a mile away peeping its brains out because it can't figure out how to get back out of its house where it went to get a snack. It can see its mothers, but can't figure out how to get to them. Oh brother, they are worse than little children because they are so curious and get lost so easily. Eeeks. Have fun with the chicks, Jerry. Beautiful and most wonderful day, lovin' this great life we all share. Cindi