There are widely varying views on what is or is not good for them. There is also some flat-out incorrect information out there. An example. Normal potato peels are fine for them. The green potato peels contain a substance that can harm humans and chickens. But the myth is out that it is all potato peels and once a myth gets started, it never dies. Normal potato peels are OK. It is the green ones that can be dangerous.
Another thing about it is that very seldom will one bite kill you or them. They are not going to fall over dead after they eat one bite. It takes a certain concentration before any harm is done. How much it takes depends on the substance and the size and health of the chicken. I’ll use apple seeds for this example. Apple seeds, like most fruit seeds, contain cyanide. Have you ever swallowed an apple seed? If so you swallowed cyanide. Why aren’t you dead? Because there is not enough cyanide in one apple seed to harm you or a chicken. I have absolutely no problem with my chickens eating an apple on the ground in my orchard. They are not going to get enough cyanide to harm themselves. When I make apple butter or apple sauce, I have a lot of seeds left over. Since I know a concentration of seeds might be harmful to them, I dispose of those seeds where the chickens can’t get at them. Would I kill my chickens if I dumped a big pile of apple seeds where they can get to them? Probably not, but since I know there is a possibility of a problem, I take what I consider reasonable precautions and don’t do that.
Another side to this is that not all damage to them is immediately evident. The damage can be to the internal organs where you can’t see it. But that kind of damage is usually due to long term exposure, not just eating one bite of something one time.
I try to practice moderation and don’t sweat the small stuff. I know certain things could possibly harm them, so I try to not give them access to large quantities of those things. But if they occasionally get a bite or two, it’s no big deal.
As far as cherries and plums. You can pit them first if you wish. It won’t hurt anything. Like apple seeds, they also contain cyanide, plum pits for sure, and probably cherries. But I found a plum pit in the gizzard of a cockerel I processed last year. They can and do eat them. One bite won’t kill them.
