tearing up his bed

Question
I have a 4 month old Lab named Willie. He is an outside dog with plenty of room to run and play with my other Lab Molly. He has toys and plenty of things to chew on. My problem is he is starting to tear his bed cushions up. He pulls them out of the his dog house and chews on it and sometimes drags it into the yard. I have gone from stuffed beds to an old comforter and now to a blanked and he is still destructive. My lab Molly was the same way when she was a puppy and out grew it, but she was never as bad as Willie. What can I do before I go broke or my dogs sleep on a hard surface.

Answer
Since tearing up his bedding appears to GET YOUR ATTENTION, your pup might very well be doing it just for that reason.  How did you address this problem with Molly??

Establish several times a day when you will go outside to interact with both your dogs.  Dogs do NOT tolerate social ostracism, they MUST interact with you, their human pack members, on a regular basis.  It is not humane to leave two dogs (or any number of dogs) alone outside without human interaction.  Learn about positive reinforcement training by going to Karen Pryor's website and use the time you're with your dogs to teach them simple behaviors for REWARD and PRAISE.  The Labrador is a breed specifically designed to partner with humans and they are very receptive to positive reinforcement.  As you interact with them, you should see this frustration diminish and, since you are ignoring the bed shredding and teaching your dog(s) behaviors that please you and earn them reward, it should soon extinguish.