Aggressive biting by three and a half month old puppy

Question
We have a 14wk old border collie-lab mix,he is inside the house at night and in the garage with the door open in the day time.When I pet him or take him for a walk in the woods on the trail behind our house he is a wild,growling severe attacking,biting maniac,We are always very gentle with him and he has ripped jeans,broke skin during these attacks.I try to give him a toy or nyla bone but he refuses and wants to bite,I'm not talking gentle puppy nipping either.I need help.

Answer
I doubt that your puppy is being aggressive and 'attacking' you. What you're describing sounds just like normal puppy behavior to me. Who said puppy nipping was gentle?! However, he does need to learn that it's inappropriate so I would suggest that you find a local trainer that can work with you one-on-one to solve the problem. Because he is so young, I do not want to give you advice on how to correct the problem because it can easily be done incorrectly. Do you have any friends or family members with puppies around the same age, or adult dogs who are good with puppies, that you can allow him to play with? It could be that he was removed from his mother and siblings too early and never learned proper interaction skills, like bite inhibition.