I need to know if there is something I can spray in my yard that will kill weeds but won't hurt the chickens. We have those weeds that have those very short burrs on them and they HURT when you step on them. They are so bad that even my dog is getting them stuck in her paws. I have 3 acres of land so I can't do any of the natural remedies that I've found like pouring boiling water on them. My husband is wanting to use roundup but I've read that it's very bad for chicken. Is there anything safe that I can use?