Will rhubarb hurt chickens if they eat it?

Rhubarb is generally considered to be toxic to chickens due to its high levels of oxalic acid. Oxalic acid can bind with calcium in the body and prevent it from being absorbed, which can lead to health problems such as soft-shelled eggs and weak bones. In addition, rhubarb leaves contain anthraquinones, which can be toxic if consumed in large quantities. For these reasons, it is generally not recommended to feed rhubarb to chickens.