Definitely no problem with paulownias here. Not sure about mimosa. Generally chickens are good at knowing what not to eat. They will even purposely eat a little bit of things which are toxic to them, as medicine.
When evil is afoot and you don't have any arms you gotta be hip and do the legwork, but always kick some ... tiny ad:
It's like being on a deserted island - only with gardens and natural buildings in Montana