I built a cage for a large boa constrictor where I screwed a large piece of driftwood to the cage (it was a plywood cage). I made sure it was super durable and stable. The snake rewarded me by never coming down. It even ate from the perch!

I think a lot of snakes would prefer to be up high than on the floor. I have a 10 ft long scrub python and its interesting that she prefers to use several smaller horizontal branches than one large one. Even rat snakes I've seen in the wild seem to prefer smaller diameter branches. Now I'm rambling, forgive me I'm fascinated with natural behavior.

Yes, screw it to the cage.

Terry