I am trying to incorporate my boxie pen close to my RF's. I discovered today that the previous owner had placed railroad ties along the back fence. Do any of you other boxie owners or those who have tortoises that dig think this will be enough to keep Jeter from digging under the fence or do I need to do more to that side of the enclosure? My enclosure back wall will butt up to the railroad tie, so that if he digs under the cinderblocks, he is going to run into the railroad ties.... Just a thought for ideas that I would put out there. Thanks in advance to all who answer.